jsmodbus - npm Package Compare versions

Comparing version 3.1.2 to 3.1.3

examples/serial/ListSerialInterfaces.js

 'use strict'
 
-var SerialPort = require('serialport')
+const SerialPort = require('serialport')
 
@@ -5,0 +5,0 @@ SerialPort.list(function (err, ports) {

examples/serial/ReadCoils.js

 'use strict'
 
-let modbus = require('../../')
-let SerialPort = require('serialport')
-let socket = new SerialPort('/dev/ttyUSB1', {
+const modbus = require('../../')
+const SerialPort = require('serialport')
+const socket = new SerialPort('/dev/ttyUSB1', {
   baudRate: 115200,
@@ -11,3 +11,3 @@ parity: 'even',
 })
-let client = new modbus.client.RTU(socket, 0x01)
+const client = new modbus.client.RTU(socket, 0x01)
 
@@ -14,0 +14,0 @@ socket.on('open', function () {

examples/serial/ReadDiscreteInput.js

 'use strict'
 'use strict'
-let modbus = require('../..')
-let Serialport = require('serialport')
-let socket = new Serialport('COM6', {
+const modbus = require('../..')
+const Serialport = require('serialport')
+const socket = new Serialport('COM6', {
   baudRate: 19200,
@@ -13,3 +13,3 @@ Parity: 'none',
 // set Slave PLC ID
-let client = new modbus.client.RTU(socket, 1)
+const client = new modbus.client.RTU(socket, 1)
 
@@ -16,0 +16,0 @@ socket.on('connect', function () {

examples/serial/ReadHoldingRegisters.js

@@ -1,4 +0,4 @@
-let modbus = require('../../')
-let SerialPort = require('serialport')
-let socket = new SerialPort('/dev/ttyUSB0', {
+const modbus = require('../../')
+const SerialPort = require('serialport')
+const socket = new SerialPort('/dev/ttyUSB0', {
   baudrate: 115200,
@@ -9,3 +9,3 @@ parity: 'even',
 
-let client = new modbus.client.RTU(socket, 1)
+const client = new modbus.client.RTU(socket, 1)
 
@@ -12,0 +12,0 @@ socket.on('close', function () {

examples/serial/ReadInputRegister.js

 'use strict'
 
-let modbus = require('../..')
-let Serialport = require('serialport')
-let socket = new Serialport('COM6', {
+const modbus = require('../..')
+const Serialport = require('serialport')
+const socket = new Serialport('COM6', {
   baudRate: 19200,
@@ -13,3 +13,3 @@ Parity: 'none',
 // set Slave PLC ID
-let client = new modbus.client.RTU(socket, 1)
+const client = new modbus.client.RTU(socket, 1)
 
@@ -16,0 +16,0 @@ socket.on('connect', function () {

examples/serial/WriteSingleCoil.js

 'use strict'
 
-let modbus = require('../..')
-let Serialport = require('serialport')
-let socket = new Serialport('COM6', {
+const modbus = require('../..')
+const Serialport = require('serialport')
+const socket = new Serialport('COM6', {
   baudRate: 19200,
@@ -13,3 +13,3 @@ Parity: 'none',
 // set Slave PLC ID
-let client = new modbus.client.RTU(socket, 1)
+const client = new modbus.client.RTU(socket, 1)
 
@@ -16,0 +16,0 @@ socket.on('connect', function () {

examples/serial/WriteSingleRegister.js

 'use strict'
 
-let modbus = require('../..')
-let Serialport = require('serialport')
-let socket = new Serialport('COM6', {
+const modbus = require('../..')
+const Serialport = require('serialport')
+const socket = new Serialport('COM6', {
   baudRate: 19200,
@@ -13,3 +13,3 @@ Parity: 'none',
 // set Slave PLC ID
-let client = new modbus.client.RTU(socket, 1)
+const client = new modbus.client.RTU(socket, 1)
 
@@ -16,0 +16,0 @@ socket.on('connect', function () {

examples/tcp/lr-allfcs-a.js

 'use strict'
 
-let modbus = require('../..')
-let net = require('net')
-let socket = new net.Socket()
-let options = {
+const modbus = require('../..')
+const net = require('net')
+const socket = new net.Socket()
+const options = {
   'host': '127.0.0.1',
   'port': '8502'
 }
-let client = new modbus.client.TCP(socket)
+const client = new modbus.client.TCP(socket)
 let cycleDone = true
@@ -21,23 +21,23 @@
 
-    let fc01 = client.readCoils(0, 40)
-    let fc02 = client.readDiscreteInputs(0, 40)
-    let fc03 = client.readHoldingRegisters(0, 100)
-    let fc04 = client.readInputRegisters(0, 100)
+    const fc01 = client.readCoils(0, 40)
+    const fc02 = client.readDiscreteInputs(0, 40)
+    const fc03 = client.readHoldingRegisters(0, 100)
+    const fc04 = client.readInputRegisters(0, 100)
 
-    let fc05StartAddress = Math.trunc(Math.random() * 1000)
-    let fc05 = client.writeSingleCoil(fc05StartAddress, true)
+    const fc05StartAddress = Math.trunc(Math.random() * 1000)
+    const fc05 = client.writeSingleCoil(fc05StartAddress, true)
 
-    let fc06StartAddress = Math.trunc(Math.random() * 100)
-    let fc06Value = Math.trunc(Math.random() * 0xFFFF)
-    let fc06 = client.writeSingleRegister(fc06StartAddress, fc06Value)
+    const fc06StartAddress = Math.trunc(Math.random() * 100)
+    const fc06Value = Math.trunc(Math.random() * 0xFFFF)
+    const fc06 = client.writeSingleRegister(fc06StartAddress, fc06Value)
 
-    let fc0FStartAddress = Math.trunc(Math.random() * 100)
-    let fc0FBufferSize = Math.trunc(Math.random() * 100)
-    let fc0F = client.writeMultipleCoils(fc0FStartAddress, Buffer.alloc(fc0FBufferSize * 2))
+    const fc0FStartAddress = Math.trunc(Math.random() * 100)
+    const fc0FBufferSize = Math.trunc(Math.random() * 100)
+    const fc0F = client.writeMultipleCoils(fc0FStartAddress, Buffer.alloc(fc0FBufferSize * 2))
 
-    let fc10StartAddress = Math.trunc(Math.random() * 100)
-    let fc10BufferSize = Math.trunc(Math.random() * 100)
-    let fc10 = client.writeMultipleCoils(fc10StartAddress, Buffer.alloc(fc10BufferSize * 2))
+    const fc10StartAddress = Math.trunc(Math.random() * 100)
+    const fc10BufferSize = Math.trunc(Math.random() * 100)
+    const fc10 = client.writeMultipleCoils(fc10StartAddress, Buffer.alloc(fc10BufferSize * 2))
 
-    let allFcs = Promise.all([fc01, fc02, fc03, fc04, fc05, fc06, fc0F, fc10])
+    const allFcs = Promise.all([fc01, fc02, fc03, fc04, fc05, fc06, fc0F, fc10])
 
@@ -44,0 +44,0 @@ allFcs.then(function () {

examples/tcp/lr-allfcs-b.js

 'use strict'
 
-let modbus = require('../..')
-let net = require('net')
-let options = {
+const modbus = require('../..')
+const net = require('net')
+const options = {
   'host': '127.0.0.1',
@@ -18,4 +18,4 @@ 'port': '8502'
 
-  let socket = new net.Socket()
-  let client = new modbus.client.TCP(socket)
+  const socket = new net.Socket()
+  const client = new modbus.client.TCP(socket)
 
@@ -27,23 +27,23 @@ socket.on('end', function () {
   socket.on('connect', function () {
-    let fc01 = client.readCoils(0, 40)
-    let fc02 = client.readDiscreteInputs(0, 40)
-    let fc03 = client.readHoldingRegisters(0, 100)
-    let fc04 = client.readInputRegisters(0, 100)
+    const fc01 = client.readCoils(0, 40)
+    const fc02 = client.readDiscreteInputs(0, 40)
+    const fc03 = client.readHoldingRegisters(0, 100)
+    const fc04 = client.readInputRegisters(0, 100)
 
-    let fc05StartAddress = Math.trunc(Math.random() * 1000)
-    let fc05 = client.writeSingleCoil(fc05StartAddress, true)
+    const fc05StartAddress = Math.trunc(Math.random() * 1000)
+    const fc05 = client.writeSingleCoil(fc05StartAddress, true)
 
-    let fc06StartAddress = Math.trunc(Math.random() * 100)
-    let fc06Value = Math.trunc(Math.random() * 0xFFFF)
-    let fc06 = client.writeSingleRegister(fc06StartAddress, fc06Value)
+    const fc06StartAddress = Math.trunc(Math.random() * 100)
+    const fc06Value = Math.trunc(Math.random() * 0xFFFF)
+    const fc06 = client.writeSingleRegister(fc06StartAddress, fc06Value)
 
-    let fc0FStartAddress = Math.trunc(Math.random() * 100)
-    let fc0FBufferSize = Math.trunc(Math.random() * 100)
-    let fc0F = client.writeMultipleCoils(fc0FStartAddress, Buffer.alloc(fc0FBufferSize * 2))
+    const fc0FStartAddress = Math.trunc(Math.random() * 100)
+    const fc0FBufferSize = Math.trunc(Math.random() * 100)
+    const fc0F = client.writeMultipleCoils(fc0FStartAddress, Buffer.alloc(fc0FBufferSize * 2))
 
-    let fc10StartAddress = Math.trunc(Math.random() * 100)
-    let fc10BufferSize = Math.trunc(Math.random() * 100)
-    let fc10 = client.writeMultipleCoils(fc10StartAddress, Buffer.alloc(fc10BufferSize * 2))
+    const fc10StartAddress = Math.trunc(Math.random() * 100)
+    const fc10BufferSize = Math.trunc(Math.random() * 100)
+    const fc10 = client.writeMultipleCoils(fc10StartAddress, Buffer.alloc(fc10BufferSize * 2))
 
-    let allFcs = Promise.all([fc01, fc02, fc03, fc04, fc05, fc06, fc0F, fc10])
+    const allFcs = Promise.all([fc01, fc02, fc03, fc04, fc05, fc06, fc0F, fc10])
 
@@ -50,0 +50,0 @@ allFcs.then(function () {

examples/tcp/lr-fc03.js

 'use strict'
 
-let modbus = require('../..')
-let net = require('net')
-let socket = new net.Socket()
-let options = {
+const modbus = require('../..')
+const net = require('net')
+const socket = new net.Socket()
+const options = {
   'host': '127.0.0.1',
   'port': '8502'
 }
-let client = new modbus.client.TCP(socket)
+const client = new modbus.client.TCP(socket)
 
@@ -12,0 +12,0 @@ socket.on('connect', function () {

examples/tcp/lr-server.js

@@ -5,6 +5,6 @@ #!/usr/bin/env node
 
-let net = require('net')
-let modbus = require('../..')
-let netServer = new net.Server()
-let server = new modbus.server.TCP(netServer)
+const net = require('net')
+const modbus = require('../..')
+const netServer = new net.Server()
+const server = new modbus.server.TCP(netServer)
 
@@ -11,0 +11,0 @@ server.on('connection', function () {

examples/tcp/ReadCoils.js

 'use strict'
 
-let modbus = require('../../')
-let net = require('net')
-let socket = new net.Socket()
-let options = {
+const modbus = require('../../')
+const net = require('net')
+const socket = new net.Socket()
+const options = {
   'host': '127.0.0.1',
   'port': '8502'
 }
-let client = new modbus.client.TCP(socket)
+const client = new modbus.client.TCP(socket)
 
@@ -12,0 +12,0 @@ socket.on('connect', function () {

examples/tcp/ReadDiscreteInputs.js

 'use strict'
 
-let modbus = require('../../')
-let net = require('net')
-let socket = new net.Socket()
-let options = {
+const modbus = require('../../')
+const net = require('net')
+const socket = new net.Socket()
+const options = {
   'host': '127.0.0.1',
   'port': '8502'
 }
-let client = new modbus.client.TCP(socket)
+const client = new modbus.client.TCP(socket)
 socket.on('connect', function () {
@@ -12,0 +12,0 @@ client.readDiscreteInputs(0, 12)

examples/tcp/ReadHoldingRegisters.js

 'use strict'
 
-let modbus = require('../..')
-let net = require('net')
-let socket = new net.Socket()
-let options = {
+const modbus = require('../..')
+const net = require('net')
+const socket = new net.Socket()
+const options = {
   'host': '127.0.0.1',
   'port': '502'
 }
-let client = new modbus.client.TCP(socket)
+const client = new modbus.client.TCP(socket)
 
@@ -12,0 +12,0 @@ socket.on('connect', function () {

examples/tcp/ReadInputRegisters.js

 'use strict'
 
-let modbus = require('../..')
-let net = require('net')
-let socket = new net.Socket()
-let options = {
+const modbus = require('../..')
+const net = require('net')
+const socket = new net.Socket()
+const options = {
   'host': '127.0.0.1',
   'port': '8502'
 }
-let client = new modbus.client.TCP(socket)
+const client = new modbus.client.TCP(socket)
 
@@ -12,0 +12,0 @@ socket.on('connect', function () {

examples/tcp/Reconnect.js

 'use strict'
 
-var modbus = require('../..')
-var client = modbus.client.tcp.complete({
+const modbus = require('../..')
+const client = modbus.client.tcp.complete({
   'host': process.argv[2],
@@ -10,9 +10,9 @@ 'port': process.argv[3],
 }).connect()
-var successCount = 0
-var errorCount = 0
-var reconnectCount = 0
-var closedOnPurpose = false
-var firstTime = true
+let successCount = 0
+let errorCount = 0
+let reconnectCount = 0
+let closedOnPurpose = false
+let firstTime = true
 
-var start = function () {
+const start = function () {
   console.log('Starting request...')
@@ -52,3 +52,3 @@
 
-var shutdown = function () {
+const shutdown = function () {
   closedOnPurpose = true
@@ -55,0 +55,0 @@

examples/tcp/SimpleServer.js

 'use strict'
 
-let net = require('net')
-let modbus = require('../..')
-let netServer = new net.Server()
-let holding = Buffer.alloc(10000)
-let server = new modbus.server.TCP(netServer, {
+const net = require('net')
+const modbus = require('../..')
+const netServer = new net.Server()
+const holding = Buffer.alloc(10000)
+const server = new modbus.server.TCP(netServer, {
   holding: holding
@@ -9,0 +9,0 @@ })

examples/tcp/WriteMultipleCoils.js

 'use strict'
 
-let modbus = require('../..')
-let net = require('net')
-let socket = new net.Socket()
-let options = {
+const modbus = require('../..')
+const net = require('net')
+const socket = new net.Socket()
+const options = {
   'host': '127.0.0.1',
   'port': '8502'
 }
-let client = new modbus.client.TCP(socket)
+const client = new modbus.client.TCP(socket)
 
 socket.on('connect', function () {
-  var values = Buffer.from([0xff])
+  const values = Buffer.from([0xff])
 
@@ -15,0 +15,0 @@ client.writeMultipleCoils(13, values, 8)

examples/tcp/WriteMultipleRegisters.js

 'use strict'
 
-let modbus = require('../..')
-let net = require('net')
-let socket = new net.Socket()
-let options = {
+const modbus = require('../..')
+const net = require('net')
+const socket = new net.Socket()
+const options = {
   'host': '127.0.0.1',
   'port': '8502'
 }
-let client = new modbus.client.TCP(socket)
+const client = new modbus.client.TCP(socket)
 
@@ -12,0 +12,0 @@ socket.on('connect', function () {

examples/tcp/WriteSingleCoil.js

 'use strict'
 
-let modbus = require('../..')
-let net = require('net')
-let socket = new net.Socket()
-let options = {
+const modbus = require('../..')
+const net = require('net')
+const socket = new net.Socket()
+const options = {
   'host': '127.0.0.1',
   'port': '8502'
 }
-let client = new modbus.client.TCP(socket)
+const client = new modbus.client.TCP(socket)
 
@@ -12,0 +12,0 @@ socket.on('connect', function () {

examples/tcp/WriteSingleRegister.js

 'use strict'
 
-let modbus = require('../..')
-let net = require('net')
-let socket = new net.Socket()
-let options = {
+const modbus = require('../..')
+const net = require('net')
+const socket = new net.Socket()
+const options = {
   'host': '192.168.56.101',
   'port': '502'
 }
-let client = new modbus.client.TCP(socket)
+const client = new modbus.client.TCP(socket)
 
@@ -12,0 +12,0 @@ socket.on('connect', function () {

package.json

 {
   "name": "jsmodbus",
-  "version": "3.1.2",
+  "version": "3.1.3",
   "description": "Implementation for the Serial/TCP Modbus protocol.",
@@ -20,2 +20,3 @@ "author": "Stefan Poeter <[e-mail]>",
     "mocha": "^3.3.0",
+    "nyc": "^13.1.0",
     "sinon": "2.2.0",
@@ -26,3 +27,4 @@ "standard": "^8.5.0"
     "test": "standard && mocha test/*.test.js",
-    "watch": "standard && mocha --watch test/*.test.js"
+    "watch": "standard && mocha --watch test/*.test.js",
+    "cov": "nyc mocha test/*.test.js"
   },
@@ -29,0 +31,0 @@ "license": "MIT",

README.md

@@ -39,7 +39,7 @@ A simple an easy to use Modbus TCP client/server implementation.
 // create a tcp modbus client
-let Modbus = require('jsmodbus')
-let net = require('net')
-let socket = new net.Socket()
-let client = new Modbus.client.TCP(socket, unitId)
-let options = {
+const Modbus = require('jsmodbus')
+const net = require('net')
+const socket = new net.Socket()
+const client = new Modbus.client.TCP(socket, unitId)
+const options = {
 'host' : host
@@ -56,9 +56,9 @@ 'port' : port
 // create a tcp modbus client
-let Modbus = require('jsmodbus')
-let SerialPort = require('serialport')
-let options = {
+const Modbus = require('jsmodbus')
+const SerialPort = require('serialport')
+const options = {
 baudRate: 57600
 }
-let socket = new SerialPort("/dev/tty-usbserial1", options)
-let client = new Modbus.client.RTU(socket, address)
+const socket = new SerialPort("/dev/tty-usbserial1", options)
+const client = new Modbus.client.RTU(socket, address)
 ```
@@ -99,6 +99,6 @@
 
-let modbus = require('jsmodbus')
-let net = require('net')
-let server = new net.Server()
-let server = new modbus.server.TCP(server)
+const modbus = require('jsmodbus')
+const net = require('net')
+const server = new net.Server()
+const server = new modbus.server.TCP(server)
 
@@ -105,0 +105,0 @@ server.listen(502)

src/buffer-utils.js

 'use strict'
 
-let debug = require('debug')('buffer-utils')
+const debug = require('debug')('buffer-utils')
 
@@ -31,10 +31,10 @@ // Buffer utilities to make simplify writing multiple coils
     startAddress = startAddress - 1
-    let startShift = startAddress % 8
-    let startByte = Math.floor(startAddress / 8)
-    let endByte = Math.floor(endAddress / 8)
+    const startShift = startAddress % 8
+    const startByte = Math.floor(startAddress / 8)
+    const endByte = Math.floor(endAddress / 8)
 
-    let size = endByte - startByte + 1
+    const size = endByte - startByte + 1
 
     // Define a new buffer
-    let buffer = Buffer.allocUnsafe(size)
+    const buffer = Buffer.allocUnsafe(size)
 
@@ -44,3 +44,3 @@ buffer[0] = outputs[0] << startShift
 
-    let paddedBuffer = Buffer.concat([outputs, Buffer.alloc(1)], outputs.length + 1)
+    const paddedBuffer = Buffer.concat([outputs, Buffer.alloc(1)], outputs.length + 1)
 
@@ -70,5 +70,5 @@ for (let i = 1; i < size; i++) {
     startAddress = startAddress - 1
-    let startShift = startAddress % 8
-    let mask = 0xff >> (8 - startShift)
-    let maskedOriginalByte = originalByte & mask
+    const startShift = startAddress % 8
+    const mask = 0xff >> (8 - startShift)
+    const maskedOriginalByte = originalByte & mask
 
@@ -85,5 +85,5 @@ return outputByte + maskedOriginalByte
   static lastByte (endAddress, originalByte, outputByte) {
-    let endShift = endAddress % 8
-    let mask = 0xff << endShift
-    let maskedOriginalByte = originalByte & mask
+    const endShift = endAddress % 8
+    const mask = 0xff << endShift
+    const maskedOriginalByte = originalByte & mask
 
@@ -94,3 +94,3 @@ return outputByte + maskedOriginalByte
   static bufferToArrayStatus (buffer) {
-    let statusArray = []
+    const statusArray = []
     let pos, curByteIdx, curByte
@@ -112,4 +112,4 @@ if (!(buffer instanceof Buffer)) {
   static arrayStatusToBuffer (array) {
-    let byteCount = array instanceof Array ? Math.ceil(array.length / 8) : 0
-    let buffer = Buffer.alloc(byteCount)
+    const byteCount = array instanceof Array ? Math.ceil(array.length / 8) : 0
+    const buffer = Buffer.alloc(byteCount)
 
@@ -116,0 +116,0 @@ if (!(array instanceof Array)) {

src/client-request-handler.js

@@ -7,5 +7,5 @@ 'use strict'
 
-let debug = require('debug')('client-request-handler')
-let UserRequest = require('./user-request.js')
-let ExceptionResponseBody = require('./response/exception.js')
+const debug = require('debug')('client-request-handler')
+const UserRequest = require('./user-request.js')
+const ExceptionResponseBody = require('./response/exception.js')
 
@@ -43,3 +43,3 @@ /** Common Request Handler
     while (this._requests.length > 0) {
-      let req = this._requests.shift()
+      const req = this._requests.shift()
       req.reject({
@@ -66,3 +66,3 @@ 'err': OUT_OF_SYNC,
   register (request) {
-    let userRequest = new UserRequest(request, this._timeout)
+    const userRequest = new UserRequest(request, this._timeout)
 
@@ -85,3 +85,3 @@ this._requests.push(userRequest)
 
-    let userRequest = this._currentRequest
+    const userRequest = this._currentRequest
 
@@ -93,3 +93,3 @@ if (!userRequest) {
 
-    let request = userRequest.request
+    const request = userRequest.request
 
@@ -157,3 +157,3 @@ /* check that response fc equals request id */
 
-    let payload = this._currentRequest.createPayload()
+    const payload = this._currentRequest.createPayload()
 
@@ -160,0 +160,0 @@ debug('flushing new request', payload)

src/modbus-client.js

@@ -1,11 +0,11 @@
-let debug = require('debug')('modbus-client')
+const debug = require('debug')('modbus-client')
 
-let ReadCoilsRequestBody = require('./request/read-coils.js')
-let ReadDiscreteInputsRequestBody = require('./request/read-discrete-inputs.js')
-let ReadHoldingRegistersRequestBody = require('./request/read-holding-registers.js')
-let ReadInputRegistersRequestBody = require('./request/read-input-registers.js')
-let WriteSingleCoilRequestBody = require('./request/write-single-coil.js')
-let WriteSingleRegisterRequestBody = require('./request/write-single-register.js')
-let WriteMultipleCoilsRequestBody = require('./request/write-multiple-coils.js')
-let WriteMultipleRegistersRequestBody = require('./request/write-multiple-registers.js')
+const ReadCoilsRequestBody = require('./request/read-coils.js')
+const ReadDiscreteInputsRequestBody = require('./request/read-discrete-inputs.js')
+const ReadHoldingRegistersRequestBody = require('./request/read-holding-registers.js')
+const ReadInputRegistersRequestBody = require('./request/read-input-registers.js')
+const WriteSingleCoilRequestBody = require('./request/write-single-coil.js')
+const WriteSingleRegisterRequestBody = require('./request/write-single-register.js')
+const WriteMultipleCoilsRequestBody = require('./request/write-multiple-coils.js')
+const WriteMultipleRegistersRequestBody = require('./request/write-multiple-registers.js')
 
@@ -42,3 +42,3 @@ /** Common Modbus Client
     do {
-      let response = this._responseHandler.shift()
+      const response = this._responseHandler.shift()
 
@@ -45,0 +45,0 @@ /* no message was parsed by now, come back later */

src/modbus-rtu-client.js

 'use strict'
 
-let ModbusClient = require('./modbus-client.js')
-let ModbusRTUClientRequestHandler = require('./rtu-client-request-handler.js')
-let ModbusRTUClientResponseHandler = require('./rtu-client-response-handler.js')
+const ModbusClient = require('./modbus-client.js')
+const ModbusRTUClientRequestHandler = require('./rtu-client-request-handler.js')
+const ModbusRTUClientResponseHandler = require('./rtu-client-response-handler.js')
 
@@ -12,6 +12,6 @@ /** This Client musst be initiated with a socket object that implements the event emitter
  * @example <caption>Create new Modbus/RTU Client</caption>
- * let Modbus = require('jsmodbus')
- * let SerialPort = require('serialport')
- * let socket = new SerialPort("/dev/tty/ttyUSB0", { "baudRate: 57600" })
- * let client = new Modbus.client.RTU(socket, address)
+ * const Modbus = require('jsmodbus')
+ * const SerialPort = require('serialport')
+ * const socket = new SerialPort("/dev/tty/ttyUSB0", { "baudRate: 57600" })
+ * const client = new Modbus.client.RTU(socket, address)
  *
@@ -18,0 +18,0 @@ * @extends ModbusClient

src/modbus-rtu-server.js

 'use strict'
 
-let ModbusServer = require('./modbus-server.js')
-let ModbusServerClient = require('./modbus-server-client.js')
-let Request = require('./rtu-request.js')
-let Response = require('./rtu-response.js')
+const ModbusServer = require('./modbus-server.js')
+const ModbusServerClient = require('./modbus-server-client.js')
+const Request = require('./rtu-request.js')
+const Response = require('./rtu-response.js')
 
@@ -12,3 +12,3 @@ class ModbusRTUServer extends ModbusServer {
     this._socket = socket
-    let client = new ModbusServerClient(this, socket, Request, Response)
+    const client = new ModbusServerClient(this, socket, Request, Response)
     this.emit('connection', client)
@@ -15,0 +15,0 @@ }

src/modbus-server-client.js

 'use strict'
 
-let debug = require('debug')('modbus tcp client socket')
-let RequestHandler = require('./modbus-server-request-handler.js')
-let ResponseHandler = require('./modbus-server-response-handler.js')
+const debug = require('debug')('modbus tcp client socket')
+const RequestHandler = require('./modbus-server-request-handler.js')
+const ResponseHandler = require('./modbus-server-response-handler.js')
 
@@ -31,3 +31,3 @@ class ModbusServerClient {
     do {
-      let request = this._requestHandler.shift()
+      const request = this._requestHandler.shift()
 
@@ -34,0 +34,0 @@ if (!request) {

src/modbus-server-request-handler.js

 'use strict'
 
-let debug = require('debug')('modbus-server-request-handler')
+const debug = require('debug')('modbus-server-request-handler')
 
@@ -21,3 +21,3 @@ class RequestHandler {
     do {
-      let request = this._requestClass.fromBuffer(this._buffer)
+      const request = this._requestClass.fromBuffer(this._buffer)
       debug('request', request)
@@ -24,0 +24,0 @@

src/modbus-server-response-handler.js

 'use strict'
 
-let debug = require('debug')('modbus tcp response handler')
+const debug = require('debug')('modbus tcp response handler')
 
@@ -26,6 +26,6 @@ class ModbusServerResponseHandler {
 
-      let ReadCoilsResponseBody = require('./response/read-coils.js')
-      let responseBody = ReadCoilsResponseBody.fromRequest(request.body, this._server.coils)
-      let response = this._responseClass.fromRequest(request, responseBody)
-      let payload = response.createPayload()
+      const ReadCoilsResponseBody = require('./response/read-coils.js')
+      const responseBody = ReadCoilsResponseBody.fromRequest(request.body, this._server.coils)
+      const response = this._responseClass.fromRequest(request, responseBody)
+      const payload = response.createPayload()
       cb(payload)
@@ -47,6 +47,6 @@
 
-      let ReadDiscreteInputsResponseBody = require('./response/read-discrete-inputs.js')
-      let responseBody = ReadDiscreteInputsResponseBody.fromRequest(request.body, this._server.discrete)
-      let response = this._responseClass.fromRequest(request, responseBody)
-      let payload = response.createPayload()
+      const ReadDiscreteInputsResponseBody = require('./response/read-discrete-inputs.js')
+      const responseBody = ReadDiscreteInputsResponseBody.fromRequest(request.body, this._server.discrete)
+      const response = this._responseClass.fromRequest(request, responseBody)
+      const payload = response.createPayload()
       cb(payload)
@@ -68,6 +68,6 @@
 
-      let ReadHoldingRegistersResponseBody = require('./response/read-holding-registers.js')
-      let responseBody = ReadHoldingRegistersResponseBody.fromRequest(request.body, this._server.holding)
-      let response = this._responseClass.fromRequest(request, responseBody)
-      let payload = response.createPayload()
+      const ReadHoldingRegistersResponseBody = require('./response/read-holding-registers.js')
+      const responseBody = ReadHoldingRegistersResponseBody.fromRequest(request.body, this._server.holding)
+      const response = this._responseClass.fromRequest(request, responseBody)
+      const payload = response.createPayload()
       cb(payload)
@@ -89,6 +89,6 @@
 
-      let ReadInputRegistersResponseBody = require('./response/read-input-registers.js')
-      let responseBody = ReadInputRegistersResponseBody.fromRequest(request.body, this._server.input)
-      let response = this._responseClass.fromRequest(request, responseBody)
-      let payload = response.createPayload()
+      const ReadInputRegistersResponseBody = require('./response/read-input-registers.js')
+      const responseBody = ReadInputRegistersResponseBody.fromRequest(request.body, this._server.input)
+      const response = this._responseClass.fromRequest(request, responseBody)
+      const payload = response.createPayload()
       cb(payload)
@@ -110,6 +110,6 @@
 
-      let WriteSingleCoilResponseBody = require('./response/write-single-coil.js')
-      let responseBody = WriteSingleCoilResponseBody.fromRequest(request.body)
+      const WriteSingleCoilResponseBody = require('./response/write-single-coil.js')
+      const responseBody = WriteSingleCoilResponseBody.fromRequest(request.body)
 
-      let address = request.body.address
+      const address = request.body.address
 
@@ -119,3 +119,3 @@ debug('Writing value %d to address %d', request.body.value, address)
       // find the byte that contains the coil to be written
-      let oldValue = this._server.coils.readUInt8(Math.floor(address / 8))
+      const oldValue = this._server.coils.readUInt8(Math.floor(address / 8))
       let newValue
@@ -125,6 +125,6 @@
         debug('illegal data value')
-        let ExceptionResponseBody = require('./response/exception.js')
+        const ExceptionResponseBody = require('./response/exception.js')
         /* illegal data value */
-        let responseBody = new ExceptionResponseBody(request.body.fc, 0x03)
-        let response = this._responseClass.fromRequest(request, responseBody)
+        const responseBody = new ExceptionResponseBody(request.body.fc, 0x03)
+        const response = this._responseClass.fromRequest(request, responseBody)
         cb(response.createPayload())
@@ -144,6 +144,6 @@ return response
         debug('illegal data address')
-        let ExceptionResponseBody = require('./response/exception.js')
+        const ExceptionResponseBody = require('./response/exception.js')
         /* illegal data address */
-        let responseBody = new ExceptionResponseBody(request.body.fc, 0x02)
-        let response = this._responseClass.fromRequest(request, responseBody)
+        const responseBody = new ExceptionResponseBody(request.body.fc, 0x02)
+        const response = this._responseClass.fromRequest(request, responseBody)
         cb(response.createPayload())
@@ -155,4 +155,4 @@ return response
 
-      let response = this._responseClass.fromRequest(request, responseBody)
-      let payload = response.createPayload()
+      const response = this._responseClass.fromRequest(request, responseBody)
+      const payload = response.createPayload()
       cb(payload)
@@ -174,11 +174,11 @@
 
-      let WriteSingleRegisterResponseBody = require('./response/write-single-register.js')
-      let responseBody = WriteSingleRegisterResponseBody.fromRequest(request.body)
+      const WriteSingleRegisterResponseBody = require('./response/write-single-register.js')
+      const responseBody = WriteSingleRegisterResponseBody.fromRequest(request.body)
 
       if (responseBody.address * 2 > this._server.holding.length) {
         debug('illegal data address')
-        let ExceptionResponseBody = require('./response/exception.js')
+        const ExceptionResponseBody = require('./response/exception.js')
         /* illegal data address */
-        let responseBody = new ExceptionResponseBody(request.body.fc, 0x02)
-        let response = this._responseClass.fromRequest(request, responseBody)
+        const responseBody = new ExceptionResponseBody(request.body.fc, 0x02)
+        const response = this._responseClass.fromRequest(request, responseBody)
         cb(response.createPayload())
@@ -190,4 +190,4 @@ return response
 
-      let response = this._responseClass.fromRequest(request, responseBody)
-      let payload = response.createPayload()
+      const response = this._responseClass.fromRequest(request, responseBody)
+      const payload = response.createPayload()
       cb(payload)
@@ -210,15 +210,15 @@
 
-      let {
+      const {
         bufferToArrayStatus,
         arrayStatusToBuffer
       } = require('./buffer-utils.js')
-      let WriteMultipleCoilsResponseBody = require('./response/write-multiple-coils.js')
+      const WriteMultipleCoilsResponseBody = require('./response/write-multiple-coils.js')
 
-      let responseBody = WriteMultipleCoilsResponseBody.fromRequest(request.body)
-      let oldStatus = bufferToArrayStatus(this._server.coils)
-      let requestCoilValues = bufferToArrayStatus(request.body.valuesAsBuffer)
-      let start = request.body.address
-      let end = start + request.body.quantity
+      const responseBody = WriteMultipleCoilsResponseBody.fromRequest(request.body)
+      const oldStatus = bufferToArrayStatus(this._server.coils)
+      const requestCoilValues = bufferToArrayStatus(request.body.valuesAsBuffer)
+      const start = request.body.address
+      const end = start + request.body.quantity
 
-      let newStatus = oldStatus.map((byte, i) => {
+      const newStatus = oldStatus.map((byte, i) => {
         return (i >= start && i < end) ? requestCoilValues.shift() : byte
@@ -231,4 +231,4 @@ })
 
-      let response = this._responseClass.fromRequest(request, responseBody)
-      let payload = response.createPayload()
+      const response = this._responseClass.fromRequest(request, responseBody)
+      const payload = response.createPayload()
       cb(payload)
@@ -251,11 +251,11 @@
 
-      let WriteMultipleRegistersResponseBody = require('./response/write-multiple-registers.js')
-      let responseBody = WriteMultipleRegistersResponseBody.fromRequest(request.body)
+      const WriteMultipleRegistersResponseBody = require('./response/write-multiple-registers.js')
+      const responseBody = WriteMultipleRegistersResponseBody.fromRequest(request.body)
 
       if (((request.body.address * 2) + request.body.values.length) > this._server.holding.length) {
         debug('illegal data address')
-        let ExceptionResponseBody = require('./response/exception.js')
+        const ExceptionResponseBody = require('./response/exception.js')
         /* illegal data address */
-        let responseBody = new ExceptionResponseBody(request.body.fc, 0x10)
-        let response = this._responseClass.fromRequest(request, responseBody)
+        const responseBody = new ExceptionResponseBody(request.body.fc, 0x10)
+        const response = this._responseClass.fromRequest(request, responseBody)
         cb(response.createPayload())
@@ -272,4 +272,4 @@ return response
 
-      let response = this._responseClass.fromRequest(request, responseBody)
-      let payload = response.createPayload()
+      const response = this._responseClass.fromRequest(request, responseBody)
+      const payload = response.createPayload()
       cb(payload)
@@ -285,5 +285,5 @@
 
-      let ExceptionResponseBody = require('./response/exception.js')
-      let responseBody = ExceptionResponseBody.fromRequest(request.body)
-      let response = this._responseClass.fromRequest(request, responseBody)
+      const ExceptionResponseBody = require('./response/exception.js')
+      const responseBody = ExceptionResponseBody.fromRequest(request.body)
+      const response = this._responseClass.fromRequest(request, responseBody)
       cb(response.createPayload())
@@ -290,0 +290,0 @@ return response

src/modbus-server.js

@@ -1,2 +0,2 @@
-let EventEmitter = require('events')
+const EventEmitter = require('events')
 
@@ -3,0 +3,0 @@ class ModbusServer extends EventEmitter {

src/modbus-tcp-client.js

 'use strict'
 
-let ModbusClient = require('./modbus-client.js')
-let ModbusTCPClientRequestHandler = require('./tcp-client-request-handler.js')
-let ModbusTCPClientResponseHandler = require('./tcp-client-response-handler.js')
+const ModbusClient = require('./modbus-client.js')
+const ModbusTCPClientRequestHandler = require('./tcp-client-request-handler.js')
+const ModbusTCPClientResponseHandler = require('./tcp-client-response-handler.js')
 
@@ -13,5 +13,5 @@ /** This client must be initiated with a net.Socket object. The module does not handle reconnections
  * @example <caption>Create new Modbus/TCP Client</caption>
- * let net = require('net')
- * let socket = new net.Socket()
- * let client = new Modbus.tcp.Client(socket)
+ * const net = require('net')
+ * const socket = new net.Socket()
+ * const client = new Modbus.tcp.Client(socket)
  *
@@ -18,0 +18,0 @@ * socket.connect({'host' : hostname, 'port' : 502 })

src/modbus-tcp-server.js

 'use strict'
 
-let debug = require('debug')('modbus tcp server')
-let ModbusServer = require('./modbus-server')
-let ModbusServerClient = require('./modbus-server-client.js')
-let Request = require('./tcp-request.js')
-let Response = require('./tcp-response.js')
+const debug = require('debug')('modbus tcp server')
+const ModbusServer = require('./modbus-server')
+const ModbusServerClient = require('./modbus-server-client.js')
+const Request = require('./tcp-request.js')
+const Response = require('./tcp-response.js')
 
@@ -19,3 +19,3 @@ class ModbusTCPServer extends ModbusServer {
     debug('new connection coming in')
-    let client = new ModbusServerClient(this, socket, Request, Response)
+    const client = new ModbusServerClient(this, socket, Request, Response)
 
@@ -22,0 +22,0 @@ this.emit('connection', client)

src/modbus.js

@@ -11,7 +11,7 @@ 'use strict'
  * @example <caption>Create new Modbus/TCP Client.</caption>
- * let Modbus = require('jsmodbus')
- * let net = require('net')
- * let socket = new new.Socket()
- * let client = new Modbus.client.TCP(socket, unitId)
- * let options = {
+ * const Modbus = require('jsmodbus')
+ * const net = require('net')
+ * const socket = new new.Socket()
+ * const client = new Modbus.client.TCP(socket, unitId)
+ * const options = {
  *   'host' : host
@@ -23,19 +23,19 @@ *   'port' : port
  */
-let ModbusTCPClient = require('./modbus-tcp-client.js')
+const ModbusTCPClient = require('./modbus-tcp-client.js')
 
 /** module:jsmodbus.client.RTU
  * @example <caption>Create new Modbus/RTU Client.</caption>
- * let Modbus = require('jsmodbus')
- * let SerialPort = require('serialport')
- * let socket = new SerialPort('/dev/tty/ttyUSB0', { baudRate: 57600 })
- * let client = new Modbus.client.TCP(socket, address)
+ * const Modbus = require('jsmodbus')
+ * const SerialPort = require('serialport')
+ * const socket = new SerialPort('/dev/tty/ttyUSB0', { baudRate: 57600 })
+ * const client = new Modbus.client.TCP(socket, address)
  */
 
-let ModbusRTUClient = require('./modbus-rtu-client.js')
+const ModbusRTUClient = require('./modbus-rtu-client.js')
 
 /** module:jsmodbus.server.TCP */
-let ModbusTCPServer = require('./modbus-tcp-server.js')
+const ModbusTCPServer = require('./modbus-tcp-server.js')
 
 /** module:jsmodbus.server.RTU */
-let ModbusRTUServer = require('./modbus-rtu-server.js')
+const ModbusRTUServer = require('./modbus-rtu-server.js')
 
@@ -42,0 +42,0 @@ module.exports = {

src/request/exception.js

@@ -1,2 +0,2 @@
-let ModbusRequestBody = require('./request-body.js')
+const ModbusRequestBody = require('./request-body.js')
 
@@ -9,3 +9,3 @@ /** Write Single Coil Request Body
     try {
-      let fc = buffer.readUInt8(0)
+      const fc = buffer.readUInt8(0)
 
@@ -37,3 +37,3 @@ if (fc > 0x2B) {
   createPayload () {
-    let payload = Buffer.alloc(2)
+    const payload = Buffer.alloc(2)
 
@@ -40,0 +40,0 @@ payload.writeUInt8(this._fc, 0) // function code

src/request/read-coils.js

@@ -1,2 +0,2 @@
-let ModbusRequestBody = require('./request-body.js')
+const ModbusRequestBody = require('./request-body.js')
 
@@ -9,3 +9,3 @@ /** Read Coils Request Body
     try {
-      let fc = buffer.readUInt8(0)
+      const fc = buffer.readUInt8(0)
 
@@ -16,4 +16,4 @@ if (fc !== 0x01) {
 
-      let start = buffer.readUInt16BE(1)
-      let quantity = buffer.readUInt16BE(3)
+      const start = buffer.readUInt16BE(1)
+      const quantity = buffer.readUInt16BE(3)
 
@@ -61,3 +61,3 @@ return new ReadCoilsRequestBody(start, quantity)
   createPayload () {
-    let payload = Buffer.alloc(5)
+    const payload = Buffer.alloc(5)
 
@@ -64,0 +64,0 @@ payload.writeUInt8(this._fc, 0) // function code

src/request/read-discrete-inputs.js

@@ -1,2 +0,2 @@
-  let ModbusRequestBody = require('./request-body.js')
+  const ModbusRequestBody = require('./request-body.js')
 
@@ -9,3 +9,3 @@ /** Read Discrete Inputs Request Body
       try {
-        let fc = buffer.readUInt8(0)
+        const fc = buffer.readUInt8(0)
 
@@ -16,4 +16,4 @@ if (fc !== 0x02) {
 
-        let start = buffer.readUInt16BE(1)
-        let quantity = buffer.readUInt16BE(3)
+        const start = buffer.readUInt16BE(1)
+        const quantity = buffer.readUInt16BE(3)
 
@@ -62,3 +62,3 @@ return new ReadDiscreteInputsRequestBody(start, quantity)
     createPayload () {
-      let payload = Buffer.alloc(5)
+      const payload = Buffer.alloc(5)
 
@@ -65,0 +65,0 @@ payload.writeUInt8(this._fc, 0) // function code

src/request/read-holding-registers.js

@@ -1,2 +0,2 @@
-let ModbusRequestBody = require('./request-body.js')
+const ModbusRequestBody = require('./request-body.js')
 
@@ -9,5 +9,5 @@ /** Read Holding Registers Request Body
     try {
-      let fc = buffer.readUInt8(0)
-      let start = buffer.readUInt16BE(1)
-      let count = buffer.readUInt16BE(3)
+      const fc = buffer.readUInt8(0)
+      const start = buffer.readUInt16BE(1)
+      const count = buffer.readUInt16BE(3)
 
@@ -61,3 +61,3 @@ if (fc !== 0x03) {
   createPayload () {
-    let payload = Buffer.alloc(5)
+    const payload = Buffer.alloc(5)
     payload.writeUInt8(this._fc, 0) // function code
@@ -64,0 +64,0 @@ payload.writeUInt16BE(this._start, 1) // start address

src/request/read-input-registers.js

@@ -1,2 +0,2 @@
-let ModbusRequestBody = require('./request-body.js')
+const ModbusRequestBody = require('./request-body.js')
 
@@ -9,5 +9,5 @@ /** Read Input Registers Request Body
     try {
-      let fc = buffer.readUInt8(0)
-      let start = buffer.readUInt16BE(1)
-      let count = buffer.readUInt16BE(3)
+      const fc = buffer.readUInt8(0)
+      const start = buffer.readUInt16BE(1)
+      const count = buffer.readUInt16BE(3)
 
@@ -57,3 +57,3 @@ if (fc !== 0x04) {
   createPayload () {
-    let payload = Buffer.alloc(5)
+    const payload = Buffer.alloc(5)
 
@@ -60,0 +60,0 @@ payload.writeUInt8(this._fc, 0) // function code

src/request/request-body.js

 'use strict'
 
-let debug = require('debug')('request-body')
+const debug = require('debug')('request-body')
 
@@ -19,34 +19,34 @@ /** Common Modbus Request Body
     try {
-      let fc = buffer.readUInt8(0)
+      const fc = buffer.readUInt8(0)
 
       if (fc === 0x01) {
-        let ReadCoilsRequest = require('./read-coils.js')
+        const ReadCoilsRequest = require('./read-coils.js')
         return ReadCoilsRequest.fromBuffer(buffer)
       }
       if (fc === 0x02) {
-        let ReadDiscreteInputsRequest = require('./read-discrete-inputs.js')
+        const ReadDiscreteInputsRequest = require('./read-discrete-inputs.js')
         return ReadDiscreteInputsRequest.fromBuffer(buffer)
       }
       if (fc === 0x03) {
-        let ReadHoldingRegistersRequest = require('./read-holding-registers.js')
+        const ReadHoldingRegistersRequest = require('./read-holding-registers.js')
         return ReadHoldingRegistersRequest.fromBuffer(buffer)
       }
       if (fc === 0x04) {
-        let ReadInputRegistersRequest = require('./read-input-registers.js')
+        const ReadInputRegistersRequest = require('./read-input-registers.js')
         return ReadInputRegistersRequest.fromBuffer(buffer)
       }
       if (fc === 0x05) {
-        let WriteSingleCoilRequest = require('./write-single-coil.js')
+        const WriteSingleCoilRequest = require('./write-single-coil.js')
         return WriteSingleCoilRequest.fromBuffer(buffer)
       }
       if (fc === 0x06) {
-        let WriteSingleRegisterRequest = require('./write-single-register.js')
+        const WriteSingleRegisterRequest = require('./write-single-register.js')
         return WriteSingleRegisterRequest.fromBuffer(buffer)
       }
       if (fc === 0x0f) {
-        let WriteMultipleCoilsResponse = require('./write-multiple-coils.js')
+        const WriteMultipleCoilsResponse = require('./write-multiple-coils.js')
         return WriteMultipleCoilsResponse.fromBuffer(buffer)
       }
       if (fc === 0x10) {
-        let WriteMultipleRegistersResponse = require('./write-multiple-registers.js')
+        const WriteMultipleRegistersResponse = require('./write-multiple-registers.js')
         return WriteMultipleRegistersResponse.fromBuffer(buffer)
@@ -57,3 +57,3 @@ }
         debug('Illegal Function (fc %d)', fc)
-        let ExceptionRequest = require('./exception.js')
+        const ExceptionRequest = require('./exception.js')
         return new ExceptionRequest(fc, 0x01)
@@ -60,0 +60,0 @@ }

src/request/write-multiple-coils.js

@@ -1,2 +0,2 @@
-let ModbusRequestBody = require('./request-body.js')
+const ModbusRequestBody = require('./request-body.js')
 
@@ -9,3 +9,3 @@ /** Write Multiple Coils Request Body
     try {
-      let fc = buffer.readUInt8(0)
+      const fc = buffer.readUInt8(0)
 
@@ -16,6 +16,6 @@ if (fc !== 0x0F) {
 
-      let address = buffer.readUInt16BE(1)
-      let quantity = buffer.readUInt16BE(3)
-      let numberOfBytes = buffer.readUInt8(5)
-      let values = buffer.slice(6, 6 + numberOfBytes)
+      const address = buffer.readUInt16BE(1)
+      const quantity = buffer.readUInt16BE(3)
+      const numberOfBytes = buffer.readUInt8(5)
+      const values = buffer.slice(6, 6 + numberOfBytes)
 
@@ -64,5 +64,5 @@ return new WriteMultipleCoilsRequestBody(address, values, quantity)
       for (let i = 0; i < this._quantity; i += 1) {
-        let pos = i % 8
-        let curByteIdx = Math.floor(i / 8)
-        let curByte = this._values.readUInt8(curByteIdx)
+        const pos = i % 8
+        const curByteIdx = Math.floor(i / 8)
+        const curByte = this._values.readUInt8(curByteIdx)
 
@@ -77,3 +77,3 @@ this._valuesAsArray.push((curByte & Math.pow(2, pos)) > 0)
       this._valuesAsArray = this._values
-      let len = Math.min(1968, this._values.length)
+      const len = Math.min(1968, this._values.length)
 
@@ -83,5 +83,5 @@ let curByte = 0
       let cntr = 0
-      let bytes = Buffer.allocUnsafe(this._numberOfBytes)
+      const bytes = Buffer.allocUnsafe(this._numberOfBytes)
 
-      for (var i = 0; i < len; i += 1) {
+      for (let i = 0; i < len; i += 1) {
         curByte += this._values[i] ? Math.pow(2, cntr) : 0
@@ -139,3 +139,3 @@
     if (this._values instanceof Buffer) {
-      let payload = Buffer.alloc(this._byteCount)
+      const payload = Buffer.alloc(this._byteCount)
       payload.writeUInt8(this._fc, 0) // function code
@@ -149,6 +149,6 @@ payload.writeUInt16BE(this._address, 1) // start address
     } else if (this._values instanceof Array) {
-      let len = Math.min(1968, this._values.length)
+      const len = Math.min(1968, this._values.length)
 
-      let payload = Buffer.alloc(6 + this._numberOfBytes)
-      let bytes = this._valuesAsBuffer
+      const payload = Buffer.alloc(6 + this._numberOfBytes)
+      const bytes = this._valuesAsBuffer
 
@@ -155,0 +155,0 @@ payload.writeUInt8(this._fc, 0) // function code

src/request/write-multiple-registers.js

@@ -1,2 +0,2 @@
-let ModbusRequestBody = require('./request-body.js')
+const ModbusRequestBody = require('./request-body.js')
 
@@ -9,6 +9,6 @@ /** Write Multiple Registers Request Body
     try {
-      let fc = buffer.readUInt8(0)
-      let address = buffer.readUInt16BE(1)
-      let numberOfBytes = buffer.readUInt8(5)
-      let values = buffer.slice(6, 6 + numberOfBytes)
+      const fc = buffer.readUInt8(0)
+      const address = buffer.readUInt16BE(1)
+      const numberOfBytes = buffer.readUInt8(5)
+      const values = buffer.slice(6, 6 + numberOfBytes)
 
@@ -105,3 +105,3 @@ if (fc !== 0x10) {
   createPayload () {
-    let payload = Buffer.alloc(6 + this._numberOfBytes)
+    const payload = Buffer.alloc(6 + this._numberOfBytes)
     payload.writeUInt8(this._fc, 0) // function code
@@ -108,0 +108,0 @@ payload.writeUInt16BE(this._address, 1) // start address

src/request/write-single-coil.js

@@ -1,2 +0,2 @@
-let ModbusRequestBody = require('./request-body.js')
+const ModbusRequestBody = require('./request-body.js')
 
@@ -9,5 +9,5 @@ /** Write Single Coil Request Body
     try {
-      let fc = buffer.readUInt8(0)
-      let address = buffer.readUInt16BE(1)
-      let value = buffer.readUInt16BE(3) === 0xff00
+      const fc = buffer.readUInt8(0)
+      const address = buffer.readUInt16BE(1)
+      const value = buffer.readUInt16BE(3) === 0xff00
 
@@ -57,3 +57,3 @@ if (fc !== 0x05) {
   createPayload () {
-    let payload = Buffer.alloc(5)
+    const payload = Buffer.alloc(5)
 
@@ -60,0 +60,0 @@ payload.writeUInt8(this._fc, 0) // function code

src/request/write-single-register.js

@@ -1,2 +0,2 @@
-let ModbusRequestBody = require('./request-body.js')
+const ModbusRequestBody = require('./request-body.js')
 
@@ -9,5 +9,5 @@ /** Write Single Register Request Body
     try {
-      let fc = buffer.readUInt8(0)
-      let address = buffer.readUInt16BE(1)
-      let value = buffer.readUInt16BE(3)
+      const fc = buffer.readUInt8(0)
+      const address = buffer.readUInt16BE(1)
+      const value = buffer.readUInt16BE(3)
 
@@ -56,3 +56,3 @@ if (fc !== 0x06) {
   createPayload () {
-    let payload = Buffer.alloc(5)
+    const payload = Buffer.alloc(5)
     payload.writeUInt8(this._fc, 0) // function code
@@ -59,0 +59,0 @@ payload.writeUInt16BE(this._address, 1) // output address

src/response/exception.js

@@ -1,2 +0,2 @@
-let Messages = {
+const Messages = {
   0x01: 'ILLEGAL FUNCTION',
@@ -13,3 +13,3 @@ 0x02: 'ILLEGAL DATA ADDRESS',
 
-let ModbusResponseBody = require('./response-body.js')
+const ModbusResponseBody = require('./response-body.js')
 
@@ -27,4 +27,4 @@ /** Modbus Excepiton Response Body
   static fromBuffer (buffer) {
-    let fc = buffer.readUInt8(0)
-    let code = buffer.readUInt8(1)
+    const fc = buffer.readUInt8(0)
+    const code = buffer.readUInt8(1)
     return new ExceptionResponseBody(fc - 0x80, code)
@@ -61,3 +61,3 @@ }
   createPayload () {
-    let payload = Buffer.alloc(2)
+    const payload = Buffer.alloc(2)
     payload.writeUInt8(this._fc, 0)
@@ -64,0 +64,0 @@ payload.writeUInt8(this._code, 1)

src/response/read-coils.js

@@ -1,3 +0,3 @@
-let debug = require('debug')('read-coils-response')
-let ModbusResponseBody = require('./response-body.js')
+const debug = require('debug')('read-coils-response')
+const ModbusResponseBody = require('./response-body.js')
 const {
@@ -20,9 +20,9 @@ bufferToArrayStatus,
   static fromRequest (requestBody, coils) {
-    let coilsStatus = bufferToArrayStatus(coils)
+    const coilsStatus = bufferToArrayStatus(coils)
 
-    let start = requestBody.start
-    let end = start + requestBody.count
+    const start = requestBody.start
+    const end = start + requestBody.count
 
     // Extract the segment of coils status
-    let coilsSegment = coilsStatus.slice(start, end)
+    const coilsSegment = coilsStatus.slice(start, end)
 
@@ -38,5 +38,5 @@ return new ReadCoilsResponseBody(coilsSegment, Math.ceil(coilsSegment.length / 8))
     try {
-      let fc = buffer.readUInt8(0)
-      let byteCount = buffer.readUInt8(1)
-      let coilStatus = buffer.slice(2, 2 + byteCount)
+      const fc = buffer.readUInt8(0)
+      const byteCount = buffer.readUInt8(1)
+      const coilStatus = buffer.slice(2, 2 + byteCount)
 
@@ -101,3 +101,3 @@ if (coilStatus.length !== byteCount) {
   createPayload () {
-    let payload = Buffer.alloc(this.byteCount)
+    const payload = Buffer.alloc(this.byteCount)
 
@@ -104,0 +104,0 @@ payload.writeUInt8(this._fc, 0)

src/response/read-discrete-inputs.js

@@ -1,2 +0,2 @@
-let ModbusResponseBody = require('./response-body.js')
+const ModbusResponseBody = require('./response-body.js')
 const {
@@ -18,9 +18,9 @@ bufferToArrayStatus,
   static fromRequest (requestBody, discreteInputs) {
-    let discreteStatus = bufferToArrayStatus(discreteInputs)
+    const discreteStatus = bufferToArrayStatus(discreteInputs)
 
-    let start = requestBody.start
-    let end = start + requestBody.count
+    const start = requestBody.start
+    const end = start + requestBody.count
 
     // Extract the segment of coils status
-    let segmentStatus = discreteStatus.slice(start, end)
+    const segmentStatus = discreteStatus.slice(start, end)
 
@@ -36,5 +36,5 @@ return new ReadDiscreteInputsResponseBody(segmentStatus, Math.ceil(segmentStatus.length / 8))
     try {
-      let fc = buffer.readUInt8(0)
-      let byteCount = buffer.readUInt8(1)
-      let coilStatus = buffer.slice(2, 2 + byteCount)
+      const fc = buffer.readUInt8(0)
+      const byteCount = buffer.readUInt8(1)
+      const coilStatus = buffer.slice(2, 2 + byteCount)
 
@@ -98,3 +98,3 @@ if (coilStatus.length !== byteCount) {
   createPayload () {
-    let payload = Buffer.alloc(this.byteCount)
+    const payload = Buffer.alloc(this.byteCount)
 
@@ -101,0 +101,0 @@ payload.writeUInt8(this._fc, 0)

src/response/read-holding-registers.js

@@ -1,3 +0,3 @@
-let ModbusResponseBody = require('./response-body.js')
-let debug = require('debug')('ReadHoldingRegistersResponseBody')
+const ModbusResponseBody = require('./response-body.js')
+const debug = require('debug')('ReadHoldingRegistersResponseBody')
 
@@ -15,6 +15,6 @@ /** Read Holding Registers ResponseBody (Function Code 0x03)
   static fromRequest (requestBody, holdingRegisters) {
-    let startByte = requestBody.start * 2
-    let endByte = (requestBody.start * 2) + (requestBody.count * 2)
+    const startByte = requestBody.start * 2
+    const endByte = (requestBody.start * 2) + (requestBody.count * 2)
 
-    let bufferSegment = holdingRegisters.slice(startByte, endByte)
+    const bufferSegment = holdingRegisters.slice(startByte, endByte)
 
@@ -31,5 +31,5 @@ /* TODO: check wheather holdingRegisters is big enough for this request */
   static fromBuffer (buffer) {
-    let fc = buffer.readUInt8(0)
-    let byteCount = buffer.readUInt8(1)
-    let payload = buffer.slice(2, 2 + byteCount)
+    const fc = buffer.readUInt8(0)
+    const byteCount = buffer.readUInt8(1)
+    const payload = buffer.slice(2, 2 + byteCount)
 
@@ -40,3 +40,3 @@ if (fc !== 0x03) {
 
-    let values = []
+    const values = []
     for (let i = 0; i < byteCount; i += 2) {
@@ -102,3 +102,3 @@ values.push(payload.readUInt16BE(i))
     if (this._values instanceof Array) {
-      let payload = Buffer.alloc(this.byteCount)
+      const payload = Buffer.alloc(this.byteCount)
       payload.writeUInt8(this._fc, 0)
@@ -105,0 +105,0 @@ payload.writeUInt8(this._byteCount, 1)

src/response/read-input-registers.js

@@ -1,2 +0,2 @@
-let ModbusResponseBody = require('./response-body.js')
+const ModbusResponseBody = require('./response-body.js')
 
@@ -14,6 +14,6 @@ /** Read Input Registers Response Body (Function Code 0x04)
   static fromRequest (requestBody, inputRegisters) {
-    let startByte = requestBody.start * 2
-    let endByte = startByte + (requestBody.count * 2)
+    const startByte = requestBody.start * 2
+    const endByte = startByte + (requestBody.count * 2)
 
-    let buf = inputRegisters.slice(startByte, endByte)
+    const buf = inputRegisters.slice(startByte, endByte)
 
@@ -28,5 +28,5 @@ return new ReadInputRegistersResponseBody(buf.length, buf)
   static fromBuffer (buffer) {
-    let fc = buffer.readUInt8(0)
-    let byteCount = buffer.readUInt8(1)
-    let payload = buffer.slice(2, 2 + byteCount)
+    const fc = buffer.readUInt8(0)
+    const byteCount = buffer.readUInt8(1)
+    const payload = buffer.slice(2, 2 + byteCount)
 
@@ -37,3 +37,3 @@ if (fc !== 0x04) {
 
-    let values = []
+    const values = []
     for (let i = 0; i < byteCount; i += 2) {
@@ -88,3 +88,3 @@ values.push(payload.readUInt16BE(i))
   createPayload () {
-    let payload = Buffer.alloc(this.byteCount)
+    const payload = Buffer.alloc(this.byteCount)
 
@@ -91,0 +91,0 @@ payload.writeUInt8(this._fc, 0)

src/response/response-body.js

@@ -8,6 +8,6 @@ 'use strict'
   static fromBuffer (buffer) {
-    let ReadCoilsResponse = require('./read-coils.js')
+    const ReadCoilsResponse = require('./read-coils.js')
 
     try {
-      let fc = buffer.readUInt8(0)
+      const fc = buffer.readUInt8(0)
 
@@ -14,0 +14,0 @@ if (fc === 0x01) {

src/response/response-factory.js

@@ -1,12 +0,12 @@
-let debug = require('debug')('response-factory')
+const debug = require('debug')('response-factory')
 
-let ExceptionResponseBody = require('./exception.js')
-let ReadCoilsResponseBody = require('./read-coils.js')
-let ReadDiscreteInputsBody = require('./read-discrete-inputs.js')
-let ReadHoldingRegistersBody = require('./read-holding-registers.js')
-let ReadInputRegistersBody = require('./read-input-registers.js')
-let WriteSingleCoilBody = require('./write-single-coil.js')
-let WriteSingleRegisterBody = require('./write-single-register.js')
-let WriteMultipleCoilsBody = require('./write-multiple-coils.js')
-let WriteMultipleRegistersBody = require('./write-multiple-registers.js')
+const ExceptionResponseBody = require('./exception.js')
+const ReadCoilsResponseBody = require('./read-coils.js')
+const ReadDiscreteInputsBody = require('./read-discrete-inputs.js')
+const ReadHoldingRegistersBody = require('./read-holding-registers.js')
+const ReadInputRegistersBody = require('./read-input-registers.js')
+const WriteSingleCoilBody = require('./write-single-coil.js')
+const WriteSingleRegisterBody = require('./write-single-register.js')
+const WriteMultipleCoilsBody = require('./write-multiple-coils.js')
+const WriteMultipleRegistersBody = require('./write-multiple-registers.js')
 
@@ -19,3 +19,3 @@ /** Response Factory
     try {
-      let fc = buffer.readUInt8(0)
+      const fc = buffer.readUInt8(0)
 
@@ -22,0 +22,0 @@ debug('fc', fc, 'payload', buffer)

src/response/write-multiple-coils.js

@@ -1,2 +0,2 @@
-let ModbusResponseBody = require('./response-body.js')
+const ModbusResponseBody = require('./response-body.js')
 
@@ -14,4 +14,4 @@ /** WriteMultipleCoils Response Body (Function Code 0x0f)
   static fromRequest (requestBody) {
-    let start = requestBody.address
-    let quantity = requestBody.quantity
+    const start = requestBody.address
+    const quantity = requestBody.quantity
 
@@ -22,5 +22,5 @@ return new WriteMultipleCoilsResponseBody(start, quantity)
   static fromBuffer (buffer) {
-    let fc = buffer.readUInt8(0)
-    let start = buffer.readUInt16BE(1)
-    let quantity = buffer.readUInt16BE(3)
+    const fc = buffer.readUInt8(0)
+    const start = buffer.readUInt16BE(1)
+    const quantity = buffer.readUInt16BE(3)
 
@@ -53,3 +53,3 @@ if (fc !== 0x0f) {
   createPayload () {
-    let payload = Buffer.alloc(this.byteCount)
+    const payload = Buffer.alloc(this.byteCount)
 
@@ -56,0 +56,0 @@ payload.writeUInt8(this._fc, 0)

src/response/write-multiple-registers.js

@@ -1,2 +0,2 @@
-let ModbusResponseBody = require('./response-body.js')
+const ModbusResponseBody = require('./response-body.js')
 
@@ -14,4 +14,4 @@ /** WriteMultipleRegisters Respone Body (Function code 0x10)
   static fromRequest (requestBody) {
-    let start = requestBody.address
-    let quantity = requestBody.quantity
+    const start = requestBody.address
+    const quantity = requestBody.quantity
 
@@ -22,5 +22,5 @@ return new WriteMultipleRegistersResponseBody(start, quantity)
   static fromBuffer (buffer) {
-    let fc = buffer.readUInt8(0)
-    let start = buffer.readUInt16BE(1)
-    let quantity = buffer.readUInt16BE(3)
+    const fc = buffer.readUInt8(0)
+    const start = buffer.readUInt16BE(1)
+    const quantity = buffer.readUInt16BE(3)
 
@@ -53,3 +53,3 @@ if (fc !== 0x10) {
   createPayload () {
-    let payload = Buffer.alloc(this.byteCount)
+    const payload = Buffer.alloc(this.byteCount)
 
@@ -56,0 +56,0 @@ payload.writeUInt8(this._fc, 0)

src/response/write-single-coil.js

@@ -1,2 +0,2 @@
-let ModbusResponseBody = require('./response-body.js')
+const ModbusResponseBody = require('./response-body.js')
 
@@ -14,4 +14,4 @@ /** Write Single Coil Response Body
   static fromRequest (requestBody) {
-    let address = requestBody.address
-    let value = requestBody.value
+    const address = requestBody.address
+    const value = requestBody.value
 
@@ -26,5 +26,5 @@ return new WriteSingleCoilResponseBody(address, value)
   static fromBuffer (buffer) {
-    let fc = buffer.readUInt8(0)
-    let address = buffer.readUInt16BE(1)
-    let value = buffer.readUInt16BE(3) === 0xFF00
+    const fc = buffer.readUInt8(0)
+    const address = buffer.readUInt16BE(1)
+    const value = buffer.readUInt16BE(3) === 0xFF00
 
@@ -57,3 +57,3 @@ if (fc !== 0x05) {
   createPayload () {
-    let payload = Buffer.alloc(this.byteCount)
+    const payload = Buffer.alloc(this.byteCount)
 
@@ -60,0 +60,0 @@ payload.writeUInt8(this._fc, 0)

src/response/write-single-register.js

@@ -1,2 +0,2 @@
-let ModbusResponseBody = require('./response-body.js')
+const ModbusResponseBody = require('./response-body.js')
 
@@ -14,4 +14,4 @@ /** WriteSingleRegister Resonse Body (Function code 0x05)
   static fromRequest (requestBody) {
-    let address = requestBody.address
-    let value = requestBody.value
+    const address = requestBody.address
+    const value = requestBody.value
 
@@ -22,5 +22,5 @@ return new WriteSingleRegisterResponseBody(address, value)
   static fromBuffer (buffer) {
-    let fc = buffer.readUInt8(0)
-    let address = buffer.readUInt16BE(1)
-    let value = buffer.readUInt16BE(3)
+    const fc = buffer.readUInt8(0)
+    const address = buffer.readUInt16BE(1)
+    const value = buffer.readUInt16BE(3)
 
@@ -53,3 +53,3 @@ if (fc !== 0x06) {
   createPayload () {
-    let payload = Buffer.alloc(5)
+    const payload = Buffer.alloc(5)
 
@@ -56,0 +56,0 @@ payload.writeUInt8(this._fc, 0)

src/rtu-client-request-handler.js

 'use strict'
 
-let debug = require('debug')('rtu-client-request-handler')
-let ModbusRTURequest = require('./rtu-request.js')
-let ModbusClientRequestHandler = require('./client-request-handler.js')
-let CRC = require('crc')
+const debug = require('debug')('rtu-client-request-handler')
+const ModbusRTURequest = require('./rtu-request.js')
+const ModbusClientRequestHandler = require('./client-request-handler.js')
+const CRC = require('crc')
 
@@ -30,3 +30,3 @@ /** Modbus/RTU Client Request Handler
 
-    let request = new ModbusRTURequest(this._address, requestBody)
+    const request = new ModbusRTURequest(this._address, requestBody)
 
@@ -42,3 +42,3 @@ return super.register(request)
 
-    let userRequest = this._currentRequest
+    const userRequest = this._currentRequest
 
@@ -50,6 +50,6 @@ if (!userRequest) {
 
-    let buf = Buffer.concat([Buffer.from([response.address]), response.body.createPayload()])
+    const buf = Buffer.concat([Buffer.from([response.address]), response.body.createPayload()])
     debug('create crc from response', buf)
 
-    let crc = CRC.crc16modbus(buf)
+    const crc = CRC.crc16modbus(buf)
 
@@ -56,0 +56,0 @@ if (response.crc !== crc) {

src/rtu-client-response-handler.js

@@ -1,4 +0,4 @@
-let debug = require('debug')('rtu-response-handler')
-let ModbusRTUResponse = require('./rtu-response.js')
-let ModbusClientResponseHandler = require('./client-response-handler.js')
+const debug = require('debug')('rtu-response-handler')
+const ModbusRTUResponse = require('./rtu-response.js')
+const ModbusClientResponseHandler = require('./client-response-handler.js')
 
@@ -17,3 +17,3 @@ /** Modbus/RTU Client Response Handler
     do {
-      let response = ModbusRTUResponse.fromBuffer(this._buffer)
+      const response = ModbusRTUResponse.fromBuffer(this._buffer)
 
@@ -20,0 +20,0 @@ if (!response) {

src/rtu-request.js

@@ -1,4 +0,4 @@
-let debug = require('debug')('rtu-request')
-let CRC = require('crc')
-let CommonRequestBody = require('./request/request-body.js')
+const debug = require('debug')('rtu-request')
+const CRC = require('crc')
+const CommonRequestBody = require('./request/request-body.js')
 
@@ -68,9 +68,9 @@ class ModbusRTURequest {
   createPayload () {
-    let bodyPayload = this._body.createPayload()
+    const bodyPayload = this._body.createPayload()
 
     this._crc = CRC.crc16modbus(Buffer.concat([Buffer.from([this._address]), bodyPayload]))
-    let crBu = Buffer.alloc(2)
+    const crBu = Buffer.alloc(2)
     crBu.writeUInt16LE(this._crc)
-    let idBuf = Buffer.from([this._address])
-    let payload = Buffer.concat([idBuf, bodyPayload, crBu])
+    const idBuf = Buffer.from([this._address])
+    const payload = Buffer.concat([idBuf, bodyPayload, crBu])
 
@@ -77,0 +77,0 @@ return payload

src/rtu-response.js

@@ -1,4 +0,4 @@
-let debug = require('debug')('rtu-response')
-let CRC = require('crc')
-let ResponseFactory = require('./response/response-factory.js')
+const debug = require('debug')('rtu-response')
+const CRC = require('crc')
+const ResponseFactory = require('./response/response-factory.js')
 
@@ -24,7 +24,7 @@ class ModbusRTUResponse {
 
-    let address = buffer.readUInt8(0)
+    const address = buffer.readUInt8(0)
 
     debug('address', address, 'buffer', buffer)
 
-    let body = ResponseFactory.fromBuffer(buffer.slice(1))
+    const body = ResponseFactory.fromBuffer(buffer.slice(1))
 
@@ -74,3 +74,3 @@ if (!body) {
      */
-    let payload = Buffer.alloc(this.byteCount)
+    const payload = Buffer.alloc(this.byteCount)
     payload.writeUInt8(this._address, 0)
@@ -77,0 +77,0 @@ const bodyPayload = this._body.createPayload()

src/tcp-client-request-handler.js

 'use strict'
 
-let debug = require('debug')('tcp-client-request-handler')
-let TCPRequest = require('./tcp-request.js')
-let ModbusClientRequestHandler = require('./client-request-handler.js')
+const debug = require('debug')('tcp-client-request-handler')
+const TCPRequest = require('./tcp-request.js')
+const ModbusClientRequestHandler = require('./client-request-handler.js')
 
@@ -34,3 +34,3 @@ const OUT_OF_SYNC = 'OutOfSync'
 
-    let tcpRequest = new TCPRequest(this._requestId, 0x00, requestBody.byteCount + 1, this._unitId, requestBody)
+    const tcpRequest = new TCPRequest(this._requestId, 0x00, requestBody.byteCount + 1, this._unitId, requestBody)
 
@@ -45,3 +45,3 @@ return super.register(tcpRequest)
 
-    let userRequest = this._currentRequest
+    const userRequest = this._currentRequest
 
@@ -53,3 +53,3 @@ if (!userRequest) {
 
-    let request = userRequest.request
+    const request = userRequest.request
 
@@ -56,0 +56,0 @@ /* check if response id equals request id */

src/tcp-client-response-handler.js

@@ -1,4 +0,4 @@
-let debug = require('debug')('tcp-response-handler')
-let TCPResponse = require('./tcp-response.js')
-let ModbusClientResponseHandler = require('./client-response-handler.js')
+const debug = require('debug')('tcp-response-handler')
+const TCPResponse = require('./tcp-response.js')
+const ModbusClientResponseHandler = require('./client-response-handler.js')
 
@@ -24,3 +24,3 @@ /** Modbus/TCP Client Response Handler.
     do {
-      let response = TCPResponse.fromBuffer(this._buffer)
+      const response = TCPResponse.fromBuffer(this._buffer)
 
@@ -27,0 +27,0 @@ if (!response) {

src/tcp-request.js

@@ -1,3 +0,3 @@
-let debug = require('debug')('tcp-request')
-let CommonRequestBody = require('./request/request-body.js')
+const debug = require('debug')('tcp-request')
+const CommonRequestBody = require('./request/request-body.js')
 
@@ -18,6 +18,6 @@ /** Class representing a Modbus TCP Request */
 
-      let id = buffer.readUInt16BE(0)
-      let protocol = buffer.readUInt16BE(2)
-      let length = buffer.readUInt16BE(4)
-      let unitId = buffer.readUInt8(6)
+      const id = buffer.readUInt16BE(0)
+      const protocol = buffer.readUInt16BE(2)
+      const length = buffer.readUInt16BE(4)
+      const unitId = buffer.readUInt8(6)
 
@@ -27,3 +27,3 @@ debug('tcp header complete, id', id, 'protocol', protocol, 'length', length, 'unitId', unitId)
 
-      let body = CommonRequestBody.fromBuffer(buffer.slice(7, 6 + length))
+      const body = CommonRequestBody.fromBuffer(buffer.slice(7, 6 + length))
 
@@ -95,4 +95,4 @@ if (!body) {
   createPayload () {
-    let body = this._body.createPayload()
-    let payload = Buffer.alloc(7 + this._body.byteCount)
+    const body = this._body.createPayload()
+    const payload = Buffer.alloc(7 + this._body.byteCount)
 
@@ -99,0 +99,0 @@ payload.writeUInt16BE(this._id, 0) // transaction id

src/tcp-response.js

@@ -1,3 +0,3 @@
-let debug = require('debug')('tcp-response')
-let ResponseFactory = require('./response/response-factory.js')
+const debug = require('debug')('tcp-response')
+const ResponseFactory = require('./response/response-factory.js')
 
@@ -29,6 +29,6 @@ /** Modbus/TCP Response
     try {
-      let id = buffer.readUInt16BE(0)
-      let protocol = buffer.readUInt16BE(2)
-      let length = buffer.readUInt16BE(4)
-      let unitId = buffer.readUInt8(6)
+      const id = buffer.readUInt16BE(0)
+      const protocol = buffer.readUInt16BE(2)
+      const length = buffer.readUInt16BE(4)
+      const unitId = buffer.readUInt8(6)
 
@@ -38,3 +38,3 @@ debug('tcp header complete, id', id, 'protocol', protocol, 'length', length, 'unitId', unitId)
 
-      let body = ResponseFactory.fromBuffer(buffer.slice(7, 7 + length - 1))
+      const body = ResponseFactory.fromBuffer(buffer.slice(7, 7 + length - 1))
 
@@ -110,3 +110,3 @@ if (!body) {
      */
-    let payload = Buffer.alloc(this.byteCount)
+    const payload = Buffer.alloc(this.byteCount)
     payload.writeUInt16BE(this._id, 0)
@@ -113,0 +113,0 @@ payload.writeUInt16BE(this._protocol, 2)

src/user-request.js

 'use strict'
 
-let debug = require('debug')('user-request')
+const debug = require('debug')('user-request')
 
@@ -5,0 +5,0 @@ /** Request created for the user. It contains the actual modbus request,

test/buffer-utils.test.js

 /* global describe, it */
 'use strict'
 
-let assert = require('assert')
-let bufferUtils = require('../src/buffer-utils.js')
+const assert = require('assert')
+const bufferUtils = require('../src/buffer-utils.js')
 
 describe('Buffer and status conversions.', function () {
   it('should convert 10 coils status to buffer 2 bytes', function () {
-    let input = [0, 0, 0, 0, 1, 0, 1, 0, 1, 0]
-    let expected = Buffer.from([0x50, 0x01])
-    let result = bufferUtils.arrayStatusToBuffer(input)
+    const input = [0, 0, 0, 0, 1, 0, 1, 0, 1, 0]
+    const expected = Buffer.from([0x50, 0x01])
+    const result = bufferUtils.arrayStatusToBuffer(input)
 
@@ -17,5 +17,5 @@ assert.deepEqual(expected, result)
   it('should convert a buffer with hex to coils/discrete array status', function () {
-    let input = Buffer.from([0x50, 0x01])
-    let expected = [0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0]
-    let result = bufferUtils.bufferToArrayStatus(input)
+    const input = Buffer.from([0x50, 0x01])
+    const expected = [0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0]
+    const result = bufferUtils.bufferToArrayStatus(input)
 
@@ -26,5 +26,5 @@ assert.deepEqual(expected, result)
   it('should convert a buffer with bin to coils/discrete array status', function () {
-    let input = Buffer.from([0b01010000, 0b00000001])
-    let expected = [0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0]
-    let result = bufferUtils.bufferToArrayStatus(input)
+    const input = Buffer.from([0b01010000, 0b00000001])
+    const expected = [0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0]
+    const result = bufferUtils.bufferToArrayStatus(input)
 
@@ -35,3 +35,3 @@ assert.deepEqual(expected, result)
   it('should return empty array if buffer is not instance of Buffer', function () {
-    let expected = []
+    const expected = []
 
@@ -52,3 +52,3 @@ let input = 0b0101000000000001
   it('should return empty buffer if coils is not instance of Array', function () {
-    let expected = Buffer.alloc(0)
+    const expected = Buffer.alloc(0)
 
@@ -73,7 +73,7 @@ let input = 0b0101000000000001
   it('should return a short buffer', function () {
-    let startAddress = 3
-    let endAddress = 7
-    let buffer = Buffer.from([0b00010001])
-    let expectedBuffer = Buffer.from([0b01000100])
-    let buf = bufferUtils.bufferShift(startAddress, endAddress, buffer)
+    const startAddress = 3
+    const endAddress = 7
+    const buffer = Buffer.from([0b00010001])
+    const expectedBuffer = Buffer.from([0b01000100])
+    const buf = bufferUtils.bufferShift(startAddress, endAddress, buffer)
 
@@ -84,7 +84,7 @@ assert(expectedBuffer.equals(buf))
   it('should return a longer buffer', function () {
-    let startAddress = 8
-    let endAddress = 17
-    let buffer = Buffer.from([0b11111111, 0b00000011])
-    let expectedBuffer = Buffer.from([0b10000000, 0b11111111, 0b00000001])
-    let buf = bufferUtils.bufferShift(startAddress, endAddress, buffer)
+    const startAddress = 8
+    const endAddress = 17
+    const buffer = Buffer.from([0b11111111, 0b00000011])
+    const expectedBuffer = Buffer.from([0b10000000, 0b11111111, 0b00000001])
+    const buf = bufferUtils.bufferShift(startAddress, endAddress, buffer)
 
@@ -95,10 +95,10 @@ assert(expectedBuffer.equals(buf))
   it('should return a correct only byte', function () {
-    let startAddress = 3
-    let endAddress = 7
-    let buffer = Buffer.from([0b00010001])
-    let buf = bufferUtils.bufferShift(startAddress, endAddress, buffer)
-    let originalBuffer = Buffer.from([0b10101010])
+    const startAddress = 3
+    const endAddress = 7
+    const buffer = Buffer.from([0b00010001])
+    const buf = bufferUtils.bufferShift(startAddress, endAddress, buffer)
+    const originalBuffer = Buffer.from([0b10101010])
     let expectedByte = 0b01000110
 
-    let firstByte = bufferUtils.firstByte(startAddress, originalBuffer[0], buf[0])
+    const firstByte = bufferUtils.firstByte(startAddress, originalBuffer[0], buf[0])
 
@@ -108,3 +108,3 @@ assert.equal(firstByte, expectedByte)
     expectedByte = 0b11000110
-    let lastByte = bufferUtils.lastByte(endAddress, originalBuffer[0], firstByte)
+    const lastByte = bufferUtils.lastByte(endAddress, originalBuffer[0], firstByte)
 
@@ -115,12 +115,12 @@ assert.equal(lastByte, expectedByte)
   it('should return a correct buffer', function () {
-    let startAddress = 10
-    let endAddress = 27
-    let buffer = Buffer.from([0b10011001, 0b10011001, 0b00000001])
-    let buf = bufferUtils.bufferShift(startAddress, endAddress, buffer)
+    const startAddress = 10
+    const endAddress = 27
+    const buffer = Buffer.from([0b10011001, 0b10011001, 0b00000001])
+    const buf = bufferUtils.bufferShift(startAddress, endAddress, buffer)
 
-    let originalBuffer = Buffer.from([0b10101010, 0b10101010, 0b10101010, 0b10101010, 0b10101010])
-    let expectedBuffer = Buffer.from([0b10101010, 0b00110010, 0b00110011, 0b10101011, 0b10101010])
+    const originalBuffer = Buffer.from([0b10101010, 0b10101010, 0b10101010, 0b10101010, 0b10101010])
+    const expectedBuffer = Buffer.from([0b10101010, 0b00110010, 0b00110011, 0b10101011, 0b10101010])
 
-    let startByte = Math.floor(startAddress / 8)
-    let firstByte = bufferUtils.firstByte(startAddress, originalBuffer[startByte], buf[0])
+    const startByte = Math.floor(startAddress / 8)
+    const firstByte = bufferUtils.firstByte(startAddress, originalBuffer[startByte], buf[0])
     let expectedByte = 0b00110010
@@ -131,4 +131,4 @@ assert.equal(firstByte, expectedByte)
 
-    let lb = Math.floor(endAddress / 8)
-    let lastByte = bufferUtils.lastByte(endAddress, originalBuffer[originalBuffer.length - 1], buf[buf.length - 1])
+    const lb = Math.floor(endAddress / 8)
+    const lastByte = bufferUtils.lastByte(endAddress, originalBuffer[originalBuffer.length - 1], buf[buf.length - 1])
     expectedByte = 0b10101011
@@ -145,12 +145,12 @@ assert.equal(lastByte, expectedByte)
   it('should return another correct buffer', function () {
-    let startAddress = 13
-    let endAddress = 20
-    let buffer = Buffer.from([0b11111111])
-    let buf = bufferUtils.bufferShift(startAddress, endAddress, buffer)
+    const startAddress = 13
+    const endAddress = 20
+    const buffer = Buffer.from([0b11111111])
+    const buf = bufferUtils.bufferShift(startAddress, endAddress, buffer)
 
-    let originalBuffer = Buffer.from([0b00000000, 0b00000000, 0b00000000, 0b00000000])
-    let expectedBuffer = Buffer.from([0b00000000, 0b11110000, 0b00001111, 0b00000000])
+    const originalBuffer = Buffer.from([0b00000000, 0b00000000, 0b00000000, 0b00000000])
+    const expectedBuffer = Buffer.from([0b00000000, 0b11110000, 0b00001111, 0b00000000])
 
-    let startByte = Math.floor(startAddress / 8)
-    let firstByte = bufferUtils.firstByte(startAddress, originalBuffer[startByte], buf[0])
+    const startByte = Math.floor(startAddress / 8)
+    const firstByte = bufferUtils.firstByte(startAddress, originalBuffer[startByte], buf[0])
     let expectedByte = 0b11110000
@@ -161,4 +161,4 @@ assert.equal(firstByte, expectedByte)
 
-    let lb = Math.floor(endAddress / 8)
-    let lastByte = bufferUtils.lastByte(endAddress, originalBuffer[originalBuffer.length - 1], buf[buf.length - 1])
+    const lb = Math.floor(endAddress / 8)
+    const lastByte = bufferUtils.lastByte(endAddress, originalBuffer[originalBuffer.length - 1], buf[buf.length - 1])
     expectedByte = 0b00001111
@@ -165,0 +165,0 @@ assert.equal(lastByte, expectedByte)

test/heap-test-coils.js

@@ -13,3 +13,3 @@ 'use strict'
 
-let request = function () {
+const request = function () {
   return client.readCoils(0, 13)
@@ -28,3 +28,3 @@ }
   p.then(function () {
-    let usedHeapSize = Math.floor(v8.getHeapStatistics().used_heap_size / 1e6)
+    const usedHeapSize = Math.floor(v8.getHeapStatistics().used_heap_size / 1e6)
 
@@ -31,0 +31,0 @@ console.log('Heap:', usedHeapSize, 'MB')

test/read-coils.test.js

@@ -5,9 +5,9 @@ 'use strict'
 
-let assert = require('assert')
+const assert = require('assert')
 
-let ModbusTCPRequest = require('../src/tcp-request.js')
-let ModbusTCPResponse = require('../src/tcp-response.js')
-let ReadCoilsRequest = require('../src/request/read-coils.js')
-let ReadCoilsResponse = require('../src/response/read-coils.js')
-let ModbusRequestBody = require('../src/request/request-body.js')
+const ModbusTCPRequest = require('../src/tcp-request.js')
+const ModbusTCPResponse = require('../src/tcp-response.js')
+const ReadCoilsRequest = require('../src/request/read-coils.js')
+const ReadCoilsResponse = require('../src/response/read-coils.js')
+const ModbusRequestBody = require('../src/request/request-body.js')
 
@@ -17,5 +17,5 @@ describe('ReadCoils Tests.', function () {
     it('should create a buffer from a read coils message', function () {
-      let response = new ReadCoilsResponse([1, 0, 1, 0, 1, 0, 1, 0, 1, 0], 2)
-      let buffer = response.createPayload()
-      let expected = Buffer.from([0x01, 0x02, 0x55, 0x01])
+      const response = new ReadCoilsResponse([1, 0, 1, 0, 1, 0, 1, 0, 1, 0], 2)
+      const buffer = response.createPayload()
+      const expected = Buffer.from([0x01, 0x02, 0x55, 0x01])
 
@@ -25,4 +25,4 @@ assert.deepEqual(expected, buffer)
     it('should create a message object from a buffer', function () {
-      let buffer = Buffer.from([0x01, 0x02, 0x55, 0x01])
-      let message = ReadCoilsResponse.fromBuffer(buffer)
+      const buffer = Buffer.from([0x01, 0x02, 0x55, 0x01])
+      const message = ReadCoilsResponse.fromBuffer(buffer)
 
@@ -35,7 +35,7 @@ assert.equal(0x01, message.fc)
     it('should mask out extra bits', function () {
-      let requestBody = ModbusRequestBody.fromBuffer(Buffer.from([0x01, 0x00, 0x00, 0x00, 0x09]))
-      let coils = Buffer.from([0xff, 0xff])
-      let response = ReadCoilsResponse.fromRequest(requestBody, coils)
-      let buffer = response.createPayload()
-      let expected = Buffer.from([0x01, 0x02, 0xff, 0x01])
+      const requestBody = ModbusRequestBody.fromBuffer(Buffer.from([0x01, 0x00, 0x00, 0x00, 0x09]))
+      const coils = Buffer.from([0xff, 0xff])
+      const response = ReadCoilsResponse.fromRequest(requestBody, coils)
+      const buffer = response.createPayload()
+      const expected = Buffer.from([0x01, 0x02, 0xff, 0x01])
 
@@ -45,7 +45,7 @@ assert.deepEqual(expected, buffer)
     it('should return an individual coil if requested', function () {
-      let requestBody = ModbusRequestBody.fromBuffer(Buffer.from([0x01, 0x00, 0x00, 0x00, 0x01]))
-      let coils = Buffer.from([0xff, 0xff])
-      let response = ReadCoilsResponse.fromRequest(requestBody, coils)
-      let buffer = response.createPayload()
-      let expected = Buffer.from([0x01, 0x01, 0x01])
+      const requestBody = ModbusRequestBody.fromBuffer(Buffer.from([0x01, 0x00, 0x00, 0x00, 0x01]))
+      const coils = Buffer.from([0xff, 0xff])
+      const response = ReadCoilsResponse.fromRequest(requestBody, coils)
+      const buffer = response.createPayload()
+      const expected = Buffer.from([0x01, 0x01, 0x01])
 
@@ -55,4 +55,4 @@ assert.deepEqual(expected, buffer)
     it('should return null on not enough buffer data', function () {
-      let buffer = Buffer.from([0x01])
-      let message = ReadCoilsResponse.fromBuffer(buffer)
+      const buffer = Buffer.from([0x01])
+      const message = ReadCoilsResponse.fromBuffer(buffer)
 
@@ -62,4 +62,4 @@ assert.ok(message === null)
     it('should return null on wrong function code', function () {
-      let buffer = Buffer.from([0x02, 0x03, 0x0a, 0x00, 0x0c])
-      let message = ReadCoilsResponse.fromBuffer(buffer)
+      const buffer = Buffer.from([0x02, 0x03, 0x0a, 0x00, 0x0c])
+      const message = ReadCoilsResponse.fromBuffer(buffer)
 
@@ -70,4 +70,4 @@ assert.ok(message === null)
     it('should return <55> when addres = 0 and count = 8 for coils <55 55 55>', function () {
-      let coils = Buffer.from([0x55, 0x55, 0x55])
-      let requestBuffer = Buffer.from([
+      const coils = Buffer.from([0x55, 0x55, 0x55])
+      const requestBuffer = Buffer.from([
         0x00, 0x01, // transaction id
@@ -81,7 +81,7 @@ 0x00, 0x00, // protocol
       ])
-      let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-      let responseBody = ReadCoilsResponse.fromRequest(request.body, coils)
-      let response = ModbusTCPResponse.fromRequest(request, responseBody)
-      let payload = response.createPayload()
-      let responseBuffer = Buffer.from([
+      const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+      const responseBody = ReadCoilsResponse.fromRequest(request.body, coils)
+      const response = ModbusTCPResponse.fromRequest(request, responseBody)
+      const payload = response.createPayload()
+      const responseBuffer = Buffer.from([
         0x00, 0x01, // transaction id
@@ -99,4 +99,4 @@ 0x00, 0x00, // protocol
     it('should return <55> when addres = 6 and count = 8 for coils <55 55 55>', function () {
-      let coils = Buffer.from([0x55, 0x55, 0x55])
-      let requestBuffer = Buffer.from([
+      const coils = Buffer.from([0x55, 0x55, 0x55])
+      const requestBuffer = Buffer.from([
         0x00, 0x01, // transaction id
@@ -110,7 +110,7 @@ 0x00, 0x00, // protocol
       ])
-      let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-      let responseBody = ReadCoilsResponse.fromRequest(request.body, coils)
-      let response = ModbusTCPResponse.fromRequest(request, responseBody)
-      let payload = response.createPayload()
-      let responseBuffer = Buffer.from([
+      const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+      const responseBody = ReadCoilsResponse.fromRequest(request.body, coils)
+      const response = ModbusTCPResponse.fromRequest(request, responseBody)
+      const payload = response.createPayload()
+      const responseBuffer = Buffer.from([
         0x00, 0x01, // transaction id
@@ -128,4 +128,4 @@ 0x00, 0x00, // protocol
     it('should return <55 01> when addres = 0 and count = 9 for coils <55 55 55>', function () {
-      let coils = Buffer.from([0x55, 0x55, 0x55])
-      let requestBuffer = Buffer.from([
+      const coils = Buffer.from([0x55, 0x55, 0x55])
+      const requestBuffer = Buffer.from([
         0x00, 0x01, // transaction id
@@ -139,7 +139,7 @@ 0x00, 0x00, // protocol
       ])
-      let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-      let responseBody = ReadCoilsResponse.fromRequest(request.body, coils)
-      let response = ModbusTCPResponse.fromRequest(request, responseBody)
-      let payload = response.createPayload()
-      let responseBuffer = Buffer.from([
+      const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+      const responseBody = ReadCoilsResponse.fromRequest(request.body, coils)
+      const response = ModbusTCPResponse.fromRequest(request, responseBody)
+      const payload = response.createPayload()
+      const responseBuffer = Buffer.from([
         0x00, 0x01, // transaction id
@@ -157,4 +157,4 @@ 0x00, 0x00, // protocol
     it('should return <2A> when addres = 1 and count = 7 for coils <55 55 55>', function () {
-      let coils = Buffer.from([0x55, 0x55, 0x55])
-      let requestBuffer = Buffer.from([
+      const coils = Buffer.from([0x55, 0x55, 0x55])
+      const requestBuffer = Buffer.from([
         0x00, 0x01, // transaction id
@@ -168,7 +168,7 @@ 0x00, 0x00, // protocol
       ])
-      let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-      let responseBody = ReadCoilsResponse.fromRequest(request.body, coils)
-      let response = ModbusTCPResponse.fromRequest(request, responseBody)
-      let payload = response.createPayload()
-      let responseBuffer = Buffer.from([
+      const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+      const responseBody = ReadCoilsResponse.fromRequest(request.body, coils)
+      const response = ModbusTCPResponse.fromRequest(request, responseBody)
+      const payload = response.createPayload()
+      const responseBuffer = Buffer.from([
         0x00, 0x01, // transaction id
@@ -186,4 +186,4 @@ 0x00, 0x00, // protocol
     it('should return <05> when addres = 0 and count = 4 for coils <55 55 55>', function () {
-      let coils = Buffer.from([0x55, 0x55, 0x55])
-      let requestBuffer = Buffer.from([
+      const coils = Buffer.from([0x55, 0x55, 0x55])
+      const requestBuffer = Buffer.from([
         0x00, 0x01, // transaction id
@@ -197,7 +197,7 @@ 0x00, 0x00, // protocol
       ])
-      let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-      let responseBody = ReadCoilsResponse.fromRequest(request.body, coils)
-      let response = ModbusTCPResponse.fromRequest(request, responseBody)
-      let payload = response.createPayload()
-      let responseBuffer = Buffer.from([
+      const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+      const responseBody = ReadCoilsResponse.fromRequest(request.body, coils)
+      const response = ModbusTCPResponse.fromRequest(request, responseBody)
+      const payload = response.createPayload()
+      const responseBuffer = Buffer.from([
         0x00, 0x01, // transaction id
@@ -215,4 +215,4 @@ 0x00, 0x00, // protocol
     it('should return <02> when addres = 1 and count = 3 for coils <55 55 55>', function () {
-      let coils = Buffer.from([0x55, 0x55, 0x55])
-      let requestBuffer = Buffer.from([
+      const coils = Buffer.from([0x55, 0x55, 0x55])
+      const requestBuffer = Buffer.from([
         0x00, 0x01, // transaction id
@@ -226,7 +226,7 @@ 0x00, 0x00, // protocol
       ])
-      let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-      let responseBody = ReadCoilsResponse.fromRequest(request.body, coils)
-      let response = ModbusTCPResponse.fromRequest(request, responseBody)
-      let payload = response.createPayload()
-      let responseBuffer = Buffer.from([
+      const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+      const responseBody = ReadCoilsResponse.fromRequest(request.body, coils)
+      const response = ModbusTCPResponse.fromRequest(request, responseBody)
+      const payload = response.createPayload()
+      const responseBuffer = Buffer.from([
         0x00, 0x01, // transaction id
@@ -247,5 +247,5 @@ 0x00, 0x00, // protocol
     it('should create a buffer from a read coils message', function () {
-      let readCoilsRequest = new ReadCoilsRequest(10, 12)
-      let buffer = readCoilsRequest.createPayload()
-      let expected = Buffer.from([0x01, 0x00, 0x0a, 0x00, 0x0c])
+      const readCoilsRequest = new ReadCoilsRequest(10, 12)
+      const buffer = readCoilsRequest.createPayload()
+      const expected = Buffer.from([0x01, 0x00, 0x0a, 0x00, 0x0c])
 
@@ -255,4 +255,4 @@ assert.deepEqual(expected, buffer)
     it('should create a message object from a buffer', function () {
-      let buffer = Buffer.from([0x01, 0x00, 0x0a, 0x00, 0x0c])
-      let message = ReadCoilsRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x01, 0x00, 0x0a, 0x00, 0x0c])
+      const message = ReadCoilsRequest.fromBuffer(buffer)
 
@@ -264,4 +264,4 @@ assert.equal(0x01, message.fc)
     it('should return null on not enough buffer data', function () {
-      let buffer = Buffer.from([0x01, 0x00])
-      let message = ReadCoilsRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x01, 0x00])
+      const message = ReadCoilsRequest.fromBuffer(buffer)
 
@@ -271,4 +271,4 @@ assert.ok(message === null)
     it('should return null on wrong function code', function () {
-      let buffer = Buffer.from([0x02, 0x00, 0x0a, 0x00, 0x0c])
-      let message = ReadCoilsRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x02, 0x00, 0x0a, 0x00, 0x0c])
+      const message = ReadCoilsRequest.fromBuffer(buffer)
 
@@ -275,0 +275,0 @@ assert.ok(message === null)

test/read-discrete-inputs.test.js

@@ -5,5 +5,5 @@ 'use strict'
 
-let assert = require('assert')
-let ReadDiscreteInputsRequest = require('../src/request/read-discrete-inputs.js')
-let ReadDiscreteInputsResponse = require('../src/response/read-discrete-inputs.js')
+const assert = require('assert')
+const ReadDiscreteInputsRequest = require('../src/request/read-discrete-inputs.js')
+const ReadDiscreteInputsResponse = require('../src/response/read-discrete-inputs.js')
 
@@ -13,5 +13,5 @@ describe('ReadDiscreteInputs Tests.', function () {
     it('should create a buffer from a read discrete inputs message', function () {
-      let response = new ReadDiscreteInputsResponse([1, 0, 1, 0, 1, 0, 1, 0, 1, 0], 2)
-      let buffer = response.createPayload()
-      let expected = Buffer.from([0x02, 0x02, 0x55, 0x01])
+      const response = new ReadDiscreteInputsResponse([1, 0, 1, 0, 1, 0, 1, 0, 1, 0], 2)
+      const buffer = response.createPayload()
+      const expected = Buffer.from([0x02, 0x02, 0x55, 0x01])
 
@@ -21,4 +21,4 @@ assert.deepEqual(expected, buffer)
     it('should create a message object from a buffer', function () {
-      let buffer = Buffer.from([0x02, 0x02, 0x55, 0x01])
-      let message = ReadDiscreteInputsResponse.fromBuffer(buffer)
+      const buffer = Buffer.from([0x02, 0x02, 0x55, 0x01])
+      const message = ReadDiscreteInputsResponse.fromBuffer(buffer)
 
@@ -31,4 +31,4 @@ assert.equal(0x02, message.fc)
     it('should return null on not enough buffer data', function () {
-      let buffer = Buffer.from([0x02])
-      let message = ReadDiscreteInputsResponse.fromBuffer(buffer)
+      const buffer = Buffer.from([0x02])
+      const message = ReadDiscreteInputsResponse.fromBuffer(buffer)
 
@@ -38,4 +38,4 @@ assert.ok(message === null)
     it('should return null on wrong function code', function () {
-      let buffer = Buffer.from([0x03, 0x03, 0x0a, 0x00, 0x0c])
-      let message = ReadDiscreteInputsResponse.fromBuffer(buffer)
+      const buffer = Buffer.from([0x03, 0x03, 0x0a, 0x00, 0x0c])
+      const message = ReadDiscreteInputsResponse.fromBuffer(buffer)
 
@@ -48,5 +48,5 @@ assert.ok(message === null)
     it('should create a buffer from a discrete inputs message', function () {
-      let readDiscreteInputsRequest = new ReadDiscreteInputsRequest(22, 33)
-      let buffer = readDiscreteInputsRequest.createPayload()
-      let expected = Buffer.from([0x02, 0x00, 0x16, 0x00, 0x21])
+      const readDiscreteInputsRequest = new ReadDiscreteInputsRequest(22, 33)
+      const buffer = readDiscreteInputsRequest.createPayload()
+      const expected = Buffer.from([0x02, 0x00, 0x16, 0x00, 0x21])
 
@@ -56,4 +56,4 @@ assert.deepEqual(expected, buffer)
     it('should create a message from a buffer', function () {
-      let buffer = Buffer.from([0x02, 0x00, 0x16, 0x00, 0x21])
-      let message = ReadDiscreteInputsRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x02, 0x00, 0x16, 0x00, 0x21])
+      const message = ReadDiscreteInputsRequest.fromBuffer(buffer)
 
@@ -66,4 +66,4 @@ assert.ok(message !== null)
     it('should return null on not enough buffer data', function () {
-      let buffer = Buffer.from([0x02, 0x00])
-      let message = ReadDiscreteInputsRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x02, 0x00])
+      const message = ReadDiscreteInputsRequest.fromBuffer(buffer)
 
@@ -73,4 +73,4 @@ assert.ok(message === null)
     it('should return null on wrong function code', function () {
-      let buffer = Buffer.from([0x03, 0x00, 0x0a, 0x00, 0x0c])
-      let message = ReadDiscreteInputsRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x03, 0x00, 0x0a, 0x00, 0x0c])
+      const message = ReadDiscreteInputsRequest.fromBuffer(buffer)
 
@@ -77,0 +77,0 @@ assert.ok(message === null)

test/read-holding-registers.test.js

@@ -5,4 +5,4 @@ 'use strict'
 
-let assert = require('assert')
-let ReadHoldingRegistersRequest = require('../src/request/read-holding-registers.js')
+const assert = require('assert')
+const ReadHoldingRegistersRequest = require('../src/request/read-holding-registers.js')
 
@@ -15,5 +15,5 @@ describe('ReadHoldingRegisters Tests.', function () {
     it('should create a buffer from a read holding registers message', function () {
-      let request = new ReadHoldingRegistersRequest(22, 33)
-      let buffer = request.createPayload()
-      let expected = Buffer.from([0x03, 0x00, 0x16, 0x00, 0x21])
+      const request = new ReadHoldingRegistersRequest(22, 33)
+      const buffer = request.createPayload()
+      const expected = Buffer.from([0x03, 0x00, 0x16, 0x00, 0x21])
 
@@ -23,4 +23,4 @@ assert.deepEqual(expected, buffer)
     it('should create a message from a buffer', function () {
-      let buffer = Buffer.from([0x03, 0x00, 0x16, 0x00, 0x21])
-      let message = ReadHoldingRegistersRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x03, 0x00, 0x16, 0x00, 0x21])
+      const message = ReadHoldingRegistersRequest.fromBuffer(buffer)
 
@@ -33,4 +33,4 @@ assert.ok(message !== null)
     it('should return null on not enough buffer data', function () {
-      let buffer = Buffer.from([0x03, 0x00])
-      let message = ReadHoldingRegistersRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x03, 0x00])
+      const message = ReadHoldingRegistersRequest.fromBuffer(buffer)
 
@@ -40,4 +40,4 @@ assert.ok(message === null)
     it('should return null on wrong function code', function () {
-      let buffer = Buffer.from([0x04, 0x00, 0x0a, 0x00, 0x0c])
-      let message = ReadHoldingRegistersRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x04, 0x00, 0x0a, 0x00, 0x0c])
+      const message = ReadHoldingRegistersRequest.fromBuffer(buffer)
 
@@ -44,0 +44,0 @@ assert.ok(message === null)

test/read-input-registers.test.js

@@ -5,4 +5,4 @@ 'use strict'
 
-let assert = require('assert')
-let ReadInputRegistersRequest = require('../src/request/read-input-registers.js')
+const assert = require('assert')
+const ReadInputRegistersRequest = require('../src/request/read-input-registers.js')
 
@@ -15,5 +15,5 @@ describe('ReadInputRegisters Tests.', function () {
     it('should create a buffer from a read input registers message', function () {
-      let request = new ReadInputRegistersRequest(22, 33)
-      let buffer = request.createPayload()
-      let expected = Buffer.from([0x04, 0x00, 0x16, 0x00, 0x21])
+      const request = new ReadInputRegistersRequest(22, 33)
+      const buffer = request.createPayload()
+      const expected = Buffer.from([0x04, 0x00, 0x16, 0x00, 0x21])
 
@@ -23,4 +23,4 @@ assert.deepEqual(expected, buffer)
     it('should create a message from a buffer', function () {
-      let buffer = Buffer.from([0x04, 0x00, 0x16, 0x00, 0x21])
-      let message = ReadInputRegistersRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x04, 0x00, 0x16, 0x00, 0x21])
+      const message = ReadInputRegistersRequest.fromBuffer(buffer)
 
@@ -33,4 +33,4 @@ assert.ok(message !== null)
     it('should return null on not enough buffer data', function () {
-      let buffer = Buffer.from([0x04, 0x00])
-      let message = ReadInputRegistersRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x04, 0x00])
+      const message = ReadInputRegistersRequest.fromBuffer(buffer)
 
@@ -40,4 +40,4 @@ assert.ok(message === null)
     it('should return null on wrong function code', function () {
-      let buffer = Buffer.from([0x05, 0x00, 0x0a, 0x00, 0x0c])
-      let message = ReadInputRegistersRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x05, 0x00, 0x0a, 0x00, 0x0c])
+      const message = ReadInputRegistersRequest.fromBuffer(buffer)
 
@@ -44,0 +44,0 @@ assert.ok(message === null)

test/response-body.test.js

@@ -5,5 +5,5 @@ 'use strict'
 
-let assert = require('assert')
-let ResponseBody = require('../src/response/response-body.js')
-let ReadCoilsResponseBody = require('../src/response/read-coils.js')
+const assert = require('assert')
+const ResponseBody = require('../src/response/response-body.js')
+const ReadCoilsResponseBody = require('../src/response/read-coils.js')
 
@@ -15,3 +15,3 @@ describe('Modbus Response Tests.', function () {
     it('should create request from buffer', function () {
-      let buffer = Buffer.from([
+      const buffer = Buffer.from([
         0x01,       // fc
@@ -23,3 +23,3 @@ 0x02,       // byte count
 
-      let response = ResponseBody.fromBuffer(buffer)
+      const response = ResponseBody.fromBuffer(buffer)
 
@@ -50,3 +50,3 @@ assert.ok(response !== null)
     it('should handle invalid buffer content', function () {
-      let buffer = Buffer.from([
+      const buffer = Buffer.from([
         0x01,       // fc
@@ -57,3 +57,3 @@ 0x02,       // byte count
 
-      let response = ReadCoilsResponseBody.fromBuffer(buffer)
+      const response = ReadCoilsResponseBody.fromBuffer(buffer)
 
@@ -60,0 +60,0 @@ assert.ok(response === null)

test/rtu-client-request-handler.test.js

 'use strict'
 
 /* global describe, it, beforeEach */
-let assert = require('assert')
-let sinon = require('sinon')
-let EventEmitter = require('events')
-let ReadCoilsRequest = require('../src/request/read-holding-registers.js')
-let ReadHoldingRegistersResponseBody = require('../src/response/read-holding-registers.js')
-let ModbusRTUResponse = require('../src/rtu-response.js')
-let ExceptionResponse = require('../src/response/exception.js')
-let ModbusRTUClientRequestHandler = require('../src/rtu-client-request-handler.js')
+const assert = require('assert')
+const sinon = require('sinon')
+const EventEmitter = require('events')
+const ReadCoilsRequest = require('../src/request/read-holding-registers.js')
+const ReadHoldingRegistersResponseBody = require('../src/response/read-holding-registers.js')
+const ModbusRTUResponse = require('../src/rtu-response.js')
+const ExceptionResponse = require('../src/response/exception.js')
+const ModbusRTUClientRequestHandler = require('../src/rtu-client-request-handler.js')
 
@@ -27,4 +27,4 @@ describe('Modbus/RTU Client Request Tests', function () {
     it('should register an rtu request', function () {
-      let handler = new ModbusRTUClientRequestHandler(socket, 4)
-      let readCoilsRequest = new ReadCoilsRequest(0x4321, 0x0120)
+      const handler = new ModbusRTUClientRequestHandler(socket, 4)
+      const readCoilsRequest = new ReadCoilsRequest(0x4321, 0x0120)
 
@@ -35,3 +35,3 @@ socket.emit('open')
 
-      let promise = handler.register(readCoilsRequest)
+      const promise = handler.register(readCoilsRequest)
 
@@ -46,7 +46,7 @@ assert.ok(promise instanceof Promise)
     it('should register an rtu request and handle a response', function (done) {
-      let ReadHoldingRegistersRequestBody = require('../src/request/read-holding-registers.js')
-      let handler = new ModbusRTUClientRequestHandler(socket, 1)
-      let request = new ReadHoldingRegistersRequestBody(0, 1)
-      let response = new ReadHoldingRegistersResponseBody(1, Buffer.from([0x00, 0x32]))
-      let rtuResponse = new ModbusRTUResponse(1, 0x91C9, response)
+      const ReadHoldingRegistersRequestBody = require('../src/request/read-holding-registers.js')
+      const handler = new ModbusRTUClientRequestHandler(socket, 1)
+      const request = new ReadHoldingRegistersRequestBody(0, 1)
+      const response = new ReadHoldingRegistersResponseBody(1, Buffer.from([0x00, 0x32]))
+      const rtuResponse = new ModbusRTUResponse(1, 0x91C9, response)
 
@@ -71,7 +71,7 @@ socket.emit('open')
     it('should register an rtu request and handle a exception response', function (done) {
-      let ReadCoilsRequest = require('../src/request/read-coils.js')
-      let handler = new ModbusRTUClientRequestHandler(socket, 4)
-      let request = new ReadCoilsRequest(0x0000, 0x0008)
-      let response = new ExceptionResponse(0x81, 0x01)
-      let rtuResponse = new ModbusRTUResponse(4, 8352, response)
+      const ReadCoilsRequest = require('../src/request/read-coils.js')
+      const handler = new ModbusRTUClientRequestHandler(socket, 4)
+      const request = new ReadCoilsRequest(0x0000, 0x0008)
+      const response = new ExceptionResponse(0x81, 0x01)
+      const rtuResponse = new ModbusRTUResponse(4, 8352, response)
 
@@ -78,0 +78,0 @@ socket.emit('open')

test/rtu-client-response-handler.test.js

@@ -5,4 +5,4 @@ 'use strict'
 
-let assert = require('assert')
-let ModbusRTUClientResponseHandler = require('../src/rtu-client-response-handler.js')
+const assert = require('assert')
+const ModbusRTUClientResponseHandler = require('../src/rtu-client-response-handler.js')
 
@@ -18,3 +18,3 @@ describe('Modbus/RTU Client Response Tests', function () {
   it('should handle a valid read coils response', function () {
-    let responseBuffer = Buffer.from([
+    const responseBuffer = Buffer.from([
       0x01,       // address
@@ -30,3 +30,3 @@ 0x01,       // function code
 
-    let response = handler.shift()
+    const response = handler.shift()
 
@@ -43,3 +43,3 @@ assert.ok(response !== null)
   it('should handle a exception', function () {
-    let responseBuffer = Buffer.from([
+    const responseBuffer = Buffer.from([
       0x01,       // address
@@ -53,3 +53,3 @@ 0x81,       // exception code for fc 0x01
 
-    let response = handler.shift()
+    const response = handler.shift()
 
@@ -63,6 +63,6 @@ assert.ok(response !== undefined)
   it('should handle a chopped response', function () {
-    let responseBufferA = Buffer.from([
+    const responseBufferA = Buffer.from([
       0x01       // address
     ])
-    let responseBufferB = Buffer.from([
+    const responseBufferB = Buffer.from([
       0x01,       // function code
@@ -69,0 +69,0 @@ 0x02,       // byte count

test/rtu-server.test.js

 /* global describe, it, beforeEach */
 'use strict'
 
-let assert = require('assert')
-let Modbus = require('../')
-let EventEmitter = require('events')
+const assert = require('assert')
+const Modbus = require('../')
+const EventEmitter = require('events')
 
@@ -8,0 +8,0 @@ describe('RTU Server Tests.', function () {

test/tcp-client.test.js

@@ -5,6 +5,6 @@ 'use strict'
 
-let assert = require('assert')
-let Modbus = require('../')
-let sinon = require('sinon')
-let EventEmitter = require('events')
+const assert = require('assert')
+const Modbus = require('../')
+const sinon = require('sinon')
+const EventEmitter = require('events')
 
@@ -25,5 +25,5 @@ describe('TCP Client Tests.', function () {
   describe('Read Coils Tests.', function () {
-    let ReadCoilsResponseBody = require('../src/response/read-coils.js')
+    const ReadCoilsResponseBody = require('../src/response/read-coils.js')
     it('should create request from buffer', function () {
-      let buffer = Buffer.from([
+      const buffer = Buffer.from([
         0x01, // fc
@@ -35,3 +35,3 @@ 0x02, // byte count
 
-      let response = ReadCoilsResponseBody.fromBuffer(buffer)
+      const response = ReadCoilsResponseBody.fromBuffer(buffer)
 
@@ -62,3 +62,3 @@ assert.ok(response !== null)
     it('should handle invalid buffer content', function () {
-      let buffer = Buffer.from([
+      const buffer = Buffer.from([
         0x01, // fc
@@ -69,3 +69,3 @@ 0x02, // byte count
 
-      let response = ReadCoilsResponseBody.fromBuffer(buffer)
+      const response = ReadCoilsResponseBody.fromBuffer(buffer)
 
@@ -75,3 +75,3 @@ assert.ok(response === null)
     it('should handle a invalid request (invalid quantity)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -91,4 +91,4 @@ socket.emit('connect')
     it('should handle a valid request with a exception response', function (done) {
-      let client = new Modbus.client.TCP(socket)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket)
+      const response = Buffer.from([
         0x00, 0x01, // transaction id
@@ -119,3 +119,3 @@ 0x00, 0x00, // protocol
     it('should handle a valid request with timeout', function (done) {
-      let client = new Modbus.client.TCP(socket, 2, 100) // unit id = 2, timeout = 100ms
+      const client = new Modbus.client.TCP(socket, 2, 100) // unit id = 2, timeout = 100ms
 
@@ -135,3 +135,3 @@ socket.emit('connect')
     it('should handle a valid request while offline', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -147,3 +147,3 @@ client.readCoils(10, 11)
     it('should handle two valid request while offline', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -166,4 +166,4 @@ client.readCoils(10, 11)
     it('should handle two valid requests', function (done) {
-      let client = new Modbus.client.TCP(socket)
-      let responseA = Buffer.from([
+      const client = new Modbus.client.TCP(socket)
+      const responseA = Buffer.from([
         0x00, 0x01, // transaction id
@@ -178,3 +178,3 @@ 0x00, 0x00, // protocol
       ])
-      let responseB = Buffer.from([
+      const responseB = Buffer.from([
         0x00, 0x02, // transaction id
@@ -211,4 +211,4 @@ 0x00, 0x00, // protocol
     it('should handle a valid request with an out of sync response', function (done) {
-      let client = new Modbus.client.TCP(socket)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket)
+      const response = Buffer.from([
         0x00, 0x02, // transaction id is WRONG!!!!
@@ -239,4 +239,4 @@ 0x00, 0x00, // protocol
     it('should handle two valid request with an out of sync response', function (done) {
-      let client = new Modbus.client.TCP(socket)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket)
+      const response = Buffer.from([
         0x00, 0x02, // transaction id is WRONG!!!!
@@ -274,4 +274,4 @@ 0x00, 0x00, // protocol
     it('should handle a valid request with an out of sync response (wrong fc)', function (done) {
-      let client = new Modbus.client.TCP(socket)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket)
+      const response = Buffer.from([
         0x00, 0x01, // transaction id
@@ -302,4 +302,4 @@ 0x00, 0x00, // protocol
     it('should handle a valid request with a wrong protocol response', function (done) {
-      let client = new Modbus.client.TCP(socket)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket)
+      const response = Buffer.from([
         0x00, 0x01, // transaction id
@@ -333,4 +333,4 @@ 0x00, 0x01, // protocol WRONG !!!!
     it('should handle a valid request', function (done) {
-      let client = new Modbus.client.TCP(socket, 2)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket, 2)
+      const response = Buffer.from([
         0x00, 0x01, // transaction id
@@ -364,3 +364,3 @@ 0x00, 0x00, // protocol
     it('should handle a invalid request (invalid start address)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -380,3 +380,3 @@ socket.emit('connect')
     it('should handle a invalid request (invalid quantity)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -398,4 +398,4 @@ socket.emit('connect')
     it('should handle a valid request', function (done) {
-      let client = new Modbus.client.TCP(socket, 2)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket, 2)
+      const response = Buffer.from([
         0x00, 0x01, // transaction id
@@ -429,3 +429,3 @@ 0x00, 0x00, // protocol
     it('should handle a invalid request (invalid start address)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -445,3 +445,3 @@ socket.emit('connect')
     it('should handle a invalid request (invalid quantity)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -463,4 +463,4 @@ socket.emit('connect')
     it('should handle a valid request', function (done) {
-      let client = new Modbus.client.TCP(socket, 2)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket, 2)
+      const response = Buffer.from([
         0x00, 0x01, // transaction id
@@ -494,3 +494,3 @@ 0x00, 0x00, // protocol
     it('should handle a invalid request (invalid start address)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -510,3 +510,3 @@ socket.emit('connect')
     it('should handle a invalid request (invalid quantity)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -528,4 +528,4 @@ socket.emit('connect')
     it('should handle a valid request', function (done) {
-      let client = new Modbus.client.TCP(socket, 2)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket, 2)
+      const response = Buffer.from([
         0x00, 0x01, // transaction id
@@ -558,3 +558,3 @@ 0x00, 0x00, // protocol
     it('should handle a invalid request (invalid start address)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -576,4 +576,4 @@ socket.emit('connect')
     it('should handle a valid request', function (done) {
-      let client = new Modbus.client.TCP(socket, 2)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket, 2)
+      const response = Buffer.from([
         0x00, 0x01, // transaction id
@@ -606,3 +606,3 @@ 0x00, 0x00, // protocol
     it('should handle a invalid request (invalid start address)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -622,3 +622,3 @@ socket.emit('connect')
     it('should handle a invalid request (invalid value, to big)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -638,3 +638,3 @@ socket.emit('connect')
     it('should handle a invalid request (invalid value, float)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -654,3 +654,3 @@ socket.emit('connect')
     it('should handle a invalid request (invalid value, negative)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -672,4 +672,4 @@ socket.emit('connect')
     it('should handle a valid request (with array)', function (done) {
-      let client = new Modbus.client.TCP(socket, 2)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket, 2)
+      const response = Buffer.from([
         0x00, 0x01, // transaction id
@@ -702,4 +702,4 @@ 0x00, 0x00, // protocol
     it('should handle a valid request (with buffer)', function (done) {
-      let client = new Modbus.client.TCP(socket, 2)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket, 2)
+      const response = Buffer.from([
         0x00, 0x01, // transaction id
@@ -733,3 +733,3 @@ 0x00, 0x00, // protocol
     it('should handle a invalid request (invalid start address)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -749,4 +749,4 @@ socket.emit('connect')
     it('should handle a invalid request (invalid array size)', function (done) {
-      let client = new Modbus.client.TCP(socket)
-      let arr = []
+      const client = new Modbus.client.TCP(socket)
+      const arr = []
 
@@ -770,4 +770,4 @@ for (let i = 0; i < (0x07b0 * 8) + 1; i += 1) {
     it('should handle a invalid request (invalid buffer size)', function (done) {
-      let client = new Modbus.client.TCP(socket)
-      let buf = Buffer.alloc(0x07b1)
+      const client = new Modbus.client.TCP(socket)
+      const buf = Buffer.alloc(0x07b1)
 
@@ -787,4 +787,4 @@ socket.emit('connect')
     it('should handle a invalid request (inconsistent buffer size)', function (done) {
-      let client = new Modbus.client.TCP(socket)
-      let buf = Buffer.alloc(0x07a0 / 8)
+      const client = new Modbus.client.TCP(socket)
+      const buf = Buffer.alloc(0x07a0 / 8)
 
@@ -806,4 +806,4 @@ socket.emit('connect')
     it('should handle a valid request (with array)', function (done) {
-      let client = new Modbus.client.TCP(socket, 2)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket, 2)
+      const response = Buffer.from([
         0x00, 0x01, // transaction id
@@ -836,4 +836,4 @@ 0x00, 0x00, // protocol
     it('should handle a valid request (with buffer)', function (done) {
-      let client = new Modbus.client.TCP(socket, 2)
-      let response = Buffer.from([
+      const client = new Modbus.client.TCP(socket, 2)
+      const response = Buffer.from([
         0x00, 0x01, // transaction id
@@ -867,3 +867,3 @@ 0x00, 0x00, // protocol
     it('should handle a invalid request (invalid start address)', function (done) {
-      let client = new Modbus.client.TCP(socket)
+      const client = new Modbus.client.TCP(socket)
 
@@ -883,4 +883,4 @@ socket.emit('connect')
     it('should handle a invalid request (invalid array size)', function (done) {
-      let client = new Modbus.client.TCP(socket)
-      let arr = []
+      const client = new Modbus.client.TCP(socket)
+      const arr = []
 
@@ -904,4 +904,4 @@ for (let i = 0; i < (0x007b + 1); i += 1) {
     it('should handle a invalid request (invalid buffer size)', function (done) {
-      let client = new Modbus.client.TCP(socket)
-      let buf = Buffer.alloc((0x007b * 2) + 1)
+      const client = new Modbus.client.TCP(socket)
+      const buf = Buffer.alloc((0x007b * 2) + 1)
 
@@ -908,0 +908,0 @@ socket.emit('connect')

test/tcp-request-handler.test.js

 'use strict'
 
 /* global describe, it, beforeEach */
-let assert = require('assert')
-let sinon = require('sinon')
-let EventEmitter = require('events')
-let TCPRequestHandler = require('../src/tcp-client-request-handler.js')
-let ReadCoilsRequest = require('../src/request/read-coils.js')
+const assert = require('assert')
+const sinon = require('sinon')
+const EventEmitter = require('events')
+const TCPRequestHandler = require('../src/tcp-client-request-handler.js')
+const ReadCoilsRequest = require('../src/request/read-coils.js')
 
@@ -23,5 +23,5 @@ describe('TCP Modbus Request Tests', function () {
   it('should write a tcp request.', function () {
-    let handler = new TCPRequestHandler(socket, 3)
-    let readCoilsRequest = new ReadCoilsRequest(0xa0fa, 0x0120)
-    let requestBuffer = Buffer.from([0x00, 0x01, 0x00, 0x00, 0x00, 0x06, 0x03, 0x01, 0xa0, 0xfa, 0x01, 0x20])
+    const handler = new TCPRequestHandler(socket, 3)
+    const readCoilsRequest = new ReadCoilsRequest(0xa0fa, 0x0120)
+    const requestBuffer = Buffer.from([0x00, 0x01, 0x00, 0x00, 0x00, 0x06, 0x03, 0x01, 0xa0, 0xfa, 0x01, 0x20])
 
@@ -33,3 +33,3 @@ socket.emit('connect')
     /* should flush the request right away */
-    let promise = handler.register(readCoilsRequest)
+    const promise = handler.register(readCoilsRequest)
 
@@ -36,0 +36,0 @@ assert.ok(promise instanceof Promise)

test/tcp-request.test.js

 /* globals describe, it */
 'use strict'
 
-let assert = require('assert')
-let TCPRequest = require('../src/tcp-request.js')
+const assert = require('assert')
+const TCPRequest = require('../src/tcp-request.js')
 
 describe('TCP Request Tests', function () {
   it('should return a valid TCPRequest object for function 15', function () {
-    let requestBuffer = Buffer.from([
+    const requestBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -21,3 +21,3 @@ 0x00, 0x00, // protocol
 
-    let request = TCPRequest.fromBuffer(requestBuffer)
+    const request = TCPRequest.fromBuffer(requestBuffer)
     assert.ok(request)
@@ -24,0 +24,0 @@ assert.equal(request.id, 0x0001)

test/tcp-response-handler.test.js

@@ -5,4 +5,4 @@ 'use strict'
 
-let assert = require('assert')
-let TCPResponseHandler = require('../src/tcp-client-response-handler.js')
+const assert = require('assert')
+const TCPResponseHandler = require('../src/tcp-client-response-handler.js')
 
@@ -19,3 +19,3 @@ describe('Modbus/TCP Client Response Handler Tests', function () {
   it('should handle a valid read coils response', function () {
-    let responseBuffer = Buffer.from([
+    const responseBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -33,3 +33,3 @@ 0x00, 0x00, // protocol
 
-    let response = handler.shift()
+    const response = handler.shift()
 
@@ -46,3 +46,3 @@ assert.ok(response !== null)
   it('should handle a exception', function () {
-    let responseBuffer = Buffer.from([
+    const responseBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -58,3 +58,3 @@ 0x00, 0x00, // protocol
 
-    let response = handler.shift()
+    const response = handler.shift()
 
@@ -72,3 +72,3 @@ assert.ok(response !== undefined)
   it('should handle a chopped response', function () {
-    let responseBufferA = Buffer.from([
+    const responseBufferA = Buffer.from([
       0x00, 0x01, // transaction id
@@ -78,3 +78,3 @@ 0x00, 0x00, // protocol
     ])
-    let responseBufferB = Buffer.from([
+    const responseBufferB = Buffer.from([
       0x03,       // unit id
@@ -81,0 +81,0 @@ 0x01,       // function code

test/tcp-server-response-handler.test.js

@@ -5,13 +5,13 @@ 'use strict'
 
-let assert = require('assert')
-let ReadCoilsResponseBody = require('../src/response/read-coils.js')
-let ReadDiscreteInputsResponseBody = require('../src/response/read-discrete-inputs.js')
-let ReadHoldingRegistersResponseBody = require('../src/response/read-holding-registers.js')
-let ReadInputRegistersResponseBody = require('../src/response/read-input-registers.js')
-let WriteSingleCoilResponseBody = require('../src/response/write-single-coil.js')
-let WriteSingleRegisterResponseBody = require('../src/response/write-single-register.js')
-let WriteMultipleCoilsResponseBody = require('../src/response/write-multiple-coils.js')
-let WriteMultipleRegistersResponseBody = require('../src/response/write-multiple-registers.js')
-let ModbusTCPResponse = require('../src/tcp-response.js')
-let ModbusTCPRequest = require('../src/tcp-request.js')
+const assert = require('assert')
+const ReadCoilsResponseBody = require('../src/response/read-coils.js')
+const ReadDiscreteInputsResponseBody = require('../src/response/read-discrete-inputs.js')
+const ReadHoldingRegistersResponseBody = require('../src/response/read-holding-registers.js')
+const ReadInputRegistersResponseBody = require('../src/response/read-input-registers.js')
+const WriteSingleCoilResponseBody = require('../src/response/write-single-coil.js')
+const WriteSingleRegisterResponseBody = require('../src/response/write-single-register.js')
+const WriteMultipleCoilsResponseBody = require('../src/response/write-multiple-coils.js')
+const WriteMultipleRegistersResponseBody = require('../src/response/write-multiple-registers.js')
+const ModbusTCPResponse = require('../src/tcp-response.js')
+const ModbusTCPRequest = require('../src/tcp-request.js')
 
@@ -22,3 +22,3 @@ describe('Modbus/TCP Server Response Handler Tests', function () {
   it('should handle a valid read coils request', function () {
-    let requestBuffer = Buffer.from([
+    const requestBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -33,11 +33,11 @@ 0x00, 0x00, // protocol
 
-    let coils = Buffer.from([
+    const coils = Buffer.from([
       0x01
     ])
 
-    let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-    let responseBody = ReadCoilsResponseBody.fromRequest(request.body, coils)
-    let response = ModbusTCPResponse.fromRequest(request, responseBody)
-    let payload = response.createPayload()
-    let responseBuffer = Buffer.from([
+    const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+    const responseBody = ReadCoilsResponseBody.fromRequest(request.body, coils)
+    const response = ModbusTCPResponse.fromRequest(request, responseBody)
+    const payload = response.createPayload()
+    const responseBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -56,3 +56,3 @@ 0x00, 0x00, // protocol
   it('should handle a valid read discrete inputs request', function () {
-    let requestBuffer = Buffer.from([
+    const requestBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -67,11 +67,11 @@ 0x00, 0x00, // protocol
 
-    let discreteInputs = Buffer.from([
+    const discreteInputs = Buffer.from([
       0xff
     ])
 
-    let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-    let responseBody = ReadDiscreteInputsResponseBody.fromRequest(request.body, discreteInputs)
-    let response = ModbusTCPResponse.fromRequest(request, responseBody)
-    let payload = response.createPayload()
-    let responseBuffer = Buffer.from([
+    const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+    const responseBody = ReadDiscreteInputsResponseBody.fromRequest(request.body, discreteInputs)
+    const response = ModbusTCPResponse.fromRequest(request, responseBody)
+    const payload = response.createPayload()
+    const responseBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -90,3 +90,3 @@ 0x00, 0x00, // protocol
   it('should handle a valid read holding registers request', function () {
-    let requestBuffer = Buffer.from([
+    const requestBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -101,3 +101,3 @@ 0x00, 0x00, // protocol
 
-    let holdingRegisters = Buffer.from([
+    const holdingRegisters = Buffer.from([
       0xff, 0x10,
@@ -109,7 +109,7 @@ 0x07, 0x08,
 
-    let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-    let responseBody = ReadHoldingRegistersResponseBody.fromRequest(request.body, holdingRegisters)
-    let response = ModbusTCPResponse.fromRequest(request, responseBody)
-    let payload = response.createPayload()
-    let responseBuffer = Buffer.from([
+    const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+    const responseBody = ReadHoldingRegistersResponseBody.fromRequest(request.body, holdingRegisters)
+    const response = ModbusTCPResponse.fromRequest(request, responseBody)
+    const payload = response.createPayload()
+    const responseBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -129,3 +129,3 @@ 0x00, 0x00, // protocol
   it('should handle a valid read input registers request', function () {
-    let requestBuffer = Buffer.from([
+    const requestBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -140,3 +140,3 @@ 0x00, 0x00, // protocol
 
-    let inputRegisters = Buffer.from([
+    const inputRegisters = Buffer.from([
       0xff, 0x10,
@@ -148,7 +148,7 @@ 0x07, 0x08,
 
-    let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-    let responseBody = ReadInputRegistersResponseBody.fromRequest(request.body, inputRegisters)
-    let response = ModbusTCPResponse.fromRequest(request, responseBody)
-    let payload = response.createPayload()
-    let responseBuffer = Buffer.from([
+    const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+    const responseBody = ReadInputRegistersResponseBody.fromRequest(request.body, inputRegisters)
+    const response = ModbusTCPResponse.fromRequest(request, responseBody)
+    const payload = response.createPayload()
+    const responseBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -168,3 +168,3 @@ 0x00, 0x00, // protocol
   it('should handle a valid write coil request', function () {
-    let requestBuffer = Buffer.from([
+    const requestBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -179,7 +179,7 @@ 0x00, 0x00, // protocol
 
-    let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-    let responseBody = WriteSingleCoilResponseBody.fromRequest(request.body)
-    let response = ModbusTCPResponse.fromRequest(request, responseBody)
-    let payload = response.createPayload()
-    let responseBuffer = Buffer.from([
+    const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+    const responseBody = WriteSingleCoilResponseBody.fromRequest(request.body)
+    const response = ModbusTCPResponse.fromRequest(request, responseBody)
+    const payload = response.createPayload()
+    const responseBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -197,3 +197,3 @@ 0x00, 0x00, // protocol
   it('should handle a valid write register request', function () {
-    let requestBuffer = Buffer.from([
+    const requestBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -208,7 +208,7 @@ 0x00, 0x00, // protocol
 
-    let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-    let responseBody = WriteSingleRegisterResponseBody.fromRequest(request.body)
-    let response = ModbusTCPResponse.fromRequest(request, responseBody)
-    let payload = response.createPayload()
-    let responseBuffer = Buffer.from([
+    const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+    const responseBody = WriteSingleRegisterResponseBody.fromRequest(request.body)
+    const response = ModbusTCPResponse.fromRequest(request, responseBody)
+    const payload = response.createPayload()
+    const responseBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -226,3 +226,3 @@ 0x00, 0x00, // protocol
   it('should handle a valid write multiple coils request', function () {
-    let requestBuffer = Buffer.from([
+    const requestBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -239,7 +239,7 @@ 0x00, 0x00, // protocol
 
-    let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-    let responseBody = WriteMultipleCoilsResponseBody.fromRequest(request.body)
-    let response = ModbusTCPResponse.fromRequest(request, responseBody)
-    let payload = response.createPayload()
-    let responseBuffer = Buffer.from([
+    const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+    const responseBody = WriteMultipleCoilsResponseBody.fromRequest(request.body)
+    const response = ModbusTCPResponse.fromRequest(request, responseBody)
+    const payload = response.createPayload()
+    const responseBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -257,3 +257,3 @@ 0x00, 0x00, // protocol
   it('should handle a valid write multiple registers request', function () {
-    let requestBuffer = Buffer.from([
+    const requestBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -271,7 +271,7 @@ 0x00, 0x00, // protocol
 
-    let request = ModbusTCPRequest.fromBuffer(requestBuffer)
-    let responseBody = WriteMultipleRegistersResponseBody.fromRequest(request.body)
-    let response = ModbusTCPResponse.fromRequest(request, responseBody)
-    let payload = response.createPayload()
-    let responseBuffer = Buffer.from([
+    const request = ModbusTCPRequest.fromBuffer(requestBuffer)
+    const responseBody = WriteMultipleRegistersResponseBody.fromRequest(request.body)
+    const response = ModbusTCPResponse.fromRequest(request, responseBody)
+    const payload = response.createPayload()
+    const responseBuffer = Buffer.from([
       0x00, 0x01, // transaction id
@@ -278,0 +278,0 @@ 0x00, 0x00, // protocol

test/tcp-server.test.js

 /* global describe, it, beforeEach */
 'use strict'
 
-let assert = require('assert')
-let Modbus = require('../')
-let EventEmitter = require('events')
+const assert = require('assert')
+const Modbus = require('../')
+const EventEmitter = require('events')
 
@@ -8,0 +8,0 @@ describe('TCP Server Tests.', function () {

test/write-multiple-coils.test.js

@@ -5,4 +5,4 @@ 'use strict'
 
-let assert = require('assert')
-let WriteMultipleCoilsRequest = require('../src/request/write-multiple-coils.js')
+const assert = require('assert')
+const WriteMultipleCoilsRequest = require('../src/request/write-multiple-coils.js')
 
@@ -16,5 +16,5 @@ describe('WriteMultipleCoils Tests.', function () {
     it('should create a buffer from a write multiple coils message', function () {
-      let request = new WriteMultipleCoilsRequest(10, [1, 0, 1, 0, 0, 1, 0, 1, 1])
-      let buffer = request.createPayload()
-      let expected = Buffer.from([0x0F, 0x00, 0x0a, 0x00, 0x09, 0x02, 0xa5, 0x01])
+      const request = new WriteMultipleCoilsRequest(10, [1, 0, 1, 0, 0, 1, 0, 1, 1])
+      const buffer = request.createPayload()
+      const expected = Buffer.from([0x0F, 0x00, 0x0a, 0x00, 0x09, 0x02, 0xa5, 0x01])
 
@@ -27,4 +27,4 @@ assert.ok(request !== null)
     it('should create a message from a buffer', function () {
-      let buffer = Buffer.from([0x0f, 0x00, 0x0a, 0x00, 0x09, 0x02, 0xa5, 0x01])
-      let message = WriteMultipleCoilsRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x0f, 0x00, 0x0a, 0x00, 0x09, 0x02, 0xa5, 0x01])
+      const message = WriteMultipleCoilsRequest.fromBuffer(buffer)
 
@@ -39,4 +39,4 @@ assert.ok(message !== null)
     it('should return null on not enough buffer data', function () {
-      let buffer = Buffer.from([0x0f, 0x00])
-      let message = WriteMultipleCoilsRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x0f, 0x00])
+      const message = WriteMultipleCoilsRequest.fromBuffer(buffer)
 
@@ -46,4 +46,4 @@ assert.ok(message === null)
     it('should return null on wrong function code', function () {
-      let buffer = Buffer.from([0x10, 0x00, 0x0a, 0xff, 0x00])
-      let message = WriteMultipleCoilsRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x10, 0x00, 0x0a, 0xff, 0x00])
+      const message = WriteMultipleCoilsRequest.fromBuffer(buffer)
 
@@ -50,0 +50,0 @@ assert.ok(message === null)

test/write-multiple-registers.test.js

@@ -5,4 +5,4 @@ 'use strict'
 
-let assert = require('assert')
-let WriteMultipleRegistersRequest = require('../src/request/write-multiple-registers.js')
+const assert = require('assert')
+const WriteMultipleRegistersRequest = require('../src/request/write-multiple-registers.js')
 
@@ -16,5 +16,5 @@ describe('WriteMultipleRegisters Tests.', function () {
     it('should create a buffer from a write multiple registers message', function () {
-      let request = new WriteMultipleRegistersRequest(10, [0x0001, 0x0002, 0x1234, 0x4321])
-      let buffer = request.createPayload()
-      let expected = Buffer.from([0x10, 0x00, 0x0a, 0x00, 0x04, 0x08, 0x00, 0x01, 0x00, 0x02, 0x12, 0x34, 0x43, 0x21])
+      const request = new WriteMultipleRegistersRequest(10, [0x0001, 0x0002, 0x1234, 0x4321])
+      const buffer = request.createPayload()
+      const expected = Buffer.from([0x10, 0x00, 0x0a, 0x00, 0x04, 0x08, 0x00, 0x01, 0x00, 0x02, 0x12, 0x34, 0x43, 0x21])
 
@@ -27,4 +27,4 @@ assert.ok(request !== null)
     it('should create a message from a buffer', function () {
-      let buffer = Buffer.from([0x10, 0x00, 0x0a, 0x00, 0x04, 0x08, 0x00, 0x01, 0x00, 0x02, 0x12, 0x34, 0x43, 0x21])
-      let message = WriteMultipleRegistersRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x10, 0x00, 0x0a, 0x00, 0x04, 0x08, 0x00, 0x01, 0x00, 0x02, 0x12, 0x34, 0x43, 0x21])
+      const message = WriteMultipleRegistersRequest.fromBuffer(buffer)
 
@@ -39,4 +39,4 @@ assert.ok(message !== null)
     it('should return null on not enough buffer data', function () {
-      let buffer = Buffer.from([0x0f, 0x00])
-      let message = WriteMultipleRegistersRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x0f, 0x00])
+      const message = WriteMultipleRegistersRequest.fromBuffer(buffer)
 
@@ -46,4 +46,4 @@ assert.ok(message === null)
     it('should return null on wrong function code', function () {
-      let buffer = Buffer.from([0x11, 0x00, 0x0a, 0xff, 0x00])
-      let message = WriteMultipleRegistersRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x11, 0x00, 0x0a, 0xff, 0x00])
+      const message = WriteMultipleRegistersRequest.fromBuffer(buffer)
 
@@ -50,0 +50,0 @@ assert.ok(message === null)

test/write-single-coil.test.js

@@ -5,4 +5,4 @@ 'use strict'
 
-let assert = require('assert')
-let WriteSingleCoilRequest = require('../src/request/write-single-coil.js')
+const assert = require('assert')
+const WriteSingleCoilRequest = require('../src/request/write-single-coil.js')
 
@@ -12,5 +12,5 @@ describe('WriteSingleCoil Tests.', function () {
     it('should create a buffer from a write single coil message', function () {
-      let request = new WriteSingleCoilRequest(10, true)
-      let buffer = request.createPayload()
-      let expected = Buffer.from([0x05, 0x00, 0x0a, 0xff, 0x00])
+      const request = new WriteSingleCoilRequest(10, true)
+      const buffer = request.createPayload()
+      const expected = Buffer.from([0x05, 0x00, 0x0a, 0xff, 0x00])
 
@@ -20,4 +20,4 @@ assert.deepEqual(expected, buffer)
     it('should create a message from a buffer', function () {
-      let buffer = Buffer.from([0x05, 0x00, 0x0a, 0xff, 0x00])
-      let message = WriteSingleCoilRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x05, 0x00, 0x0a, 0xff, 0x00])
+      const message = WriteSingleCoilRequest.fromBuffer(buffer)
 
@@ -30,4 +30,4 @@ assert.ok(message !== null)
     it('should return null on not enough buffer data', function () {
-      let buffer = Buffer.from([0x05, 0x00])
-      let message = WriteSingleCoilRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x05, 0x00])
+      const message = WriteSingleCoilRequest.fromBuffer(buffer)
 
@@ -37,4 +37,4 @@ assert.ok(message === null)
     it('should return null on wrong function code', function () {
-      let buffer = Buffer.from([0x06, 0x00, 0x0a, 0xff, 0x00])
-      let message = WriteSingleCoilRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x06, 0x00, 0x0a, 0xff, 0x00])
+      const message = WriteSingleCoilRequest.fromBuffer(buffer)
 
@@ -41,0 +41,0 @@ assert.ok(message === null)

test/write-single-register.test.js

@@ -5,4 +5,4 @@ 'use strict'
 
-let assert = require('assert')
-let WriteSingleRegisterRequest = require('../src/request/write-single-register.js')
+const assert = require('assert')
+const WriteSingleRegisterRequest = require('../src/request/write-single-register.js')
 
@@ -16,5 +16,5 @@ describe('WriteSingleRegister Tests.', function () {
     it('should create a buffer from a write single register message', function () {
-      let request = new WriteSingleRegisterRequest(10, 0x1234)
-      let buffer = request.createPayload()
-      let expected = Buffer.from([0x06, 0x00, 0x0a, 0x12, 0x34])
+      const request = new WriteSingleRegisterRequest(10, 0x1234)
+      const buffer = request.createPayload()
+      const expected = Buffer.from([0x06, 0x00, 0x0a, 0x12, 0x34])
 
@@ -24,4 +24,4 @@ assert.deepEqual(expected, buffer)
     it('should create a message from a buffer', function () {
-      let buffer = Buffer.from([0x06, 0x00, 0x0a, 0x12, 0x34])
-      let message = WriteSingleRegisterRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x06, 0x00, 0x0a, 0x12, 0x34])
+      const message = WriteSingleRegisterRequest.fromBuffer(buffer)
 
@@ -34,4 +34,4 @@ assert.ok(message !== null)
     it('should return null on not enough buffer data', function () {
-      let buffer = Buffer.from([0x05, 0x00])
-      let message = WriteSingleRegisterRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x05, 0x00])
+      const message = WriteSingleRegisterRequest.fromBuffer(buffer)
 
@@ -41,4 +41,4 @@ assert.ok(message === null)
     it('should return null on wrong function code', function () {
-      let buffer = Buffer.from([0x07, 0x00, 0x0a, 0xff, 0x00])
-      let message = WriteSingleRegisterRequest.fromBuffer(buffer)
+      const buffer = Buffer.from([0x07, 0x00, 0x0a, 0xff, 0x00])
+      const message = WriteSingleRegisterRequest.fromBuffer(buffer)
 
@@ -45,0 +45,0 @@ assert.ok(message === null)

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decreased by-6.66%

Dev dependency count

4

increased by33.33%

Number of package files

89

decreased by-11%

Lines of code

6026

decreased by-8%

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