pyTMCL

Python TMCL client library

Clone of NativeDesign/python-tmcl

Python wrapper around Trinamic's TMCL serial interface for controlling TMCM stepper modules via a serial-to-rs485 converter.

Installation

Install using pip

> pip install pytmcl

Install without pip

> git clone https://github.com/LukeSkywalker92/pyTMCL.git
> cd pyTMCL
> python setup.py install

Usage

Use an RS485-to-serial adapter to connect your PC to one or more TMCM modules. Before starting you should check the modules' serial-address and baud-rate is a known value. Out of the box (warning: anecdotal) modules usually have an address of 1 and a baud-rate of 9600 but this is not guarenteed. The easiest way to check these values is by using the TMCL IDE on a windows machine.

If using multiple TMCM modules attached to the same rs485 bus you must ensure that each module is set to a different serial-address so that they don't clash.

Example usage (single-axis modules)

from serial import Serial
from time import sleep
import pyTMCL

## serial-address as set on the TMCM module.
MODULE_ADDRESS = 1

## Open the serial port presented by your rs485 adapter
serial_port = Serial("/dev/tty.usbmodem1241")

## Create a Bus instance using the open serial port
bus = pyTMCL.connect(serial_port)

## Get the motor
motor = bus.get_motor(MODULE_ADDRESS)

## From this point you can start issuing TMCL commands
## to the motor as per the TMCL docs. This example will
## rotate the motor left at a speed of 1234 for 2 seconds
motor.rotate_left(1234)
sleep(2)
motor.stop()

Example usage (multi-axis modules)

from serial import Serial
import pyTMCL

## Open the serial port presented by your rs485 adapter
serial_port = Serial("/dev/tty.usbmodem1241")

## Create a Bus instance using the open serial port
bus = pyTMCL.connect(serial_port)

## Get the motor on axis 0 of module with address 1
module = bus.get_module( 1 )

a0 = module.get_motor(0)
a1 = module.get_motor(1)
a2 = module.get_motor(2)

Example usage (callbacks)

from serial import Serial
from time import sleep
import pyTMCL

# serial-address as set on the TMCM module.
MODULE_ADDRESS = 0

# Open the serial port presented by your rs485 adapter
serial_port = Serial("COM4")

# Create a Bus instance using the open serial port
bus = pyTMCL.connect(serial_port)

# Get the motor
motor = bus.get_motor(MODULE_ADDRESS)
motor.axis.max_positioning_speed = 200
# From this point you can start issuing pyTMCL commands
# to the motor as per the pyTMCL docs. This example will
# rotate the motor left at a speed of 1234 for 2 seconds


def angle_to_steps(angle):
    return int(angle * 256 / 1.8)

def callback(arg1, arg2):
	print("Argument 1: " + str(arg1) + "  Argument2: " + str(arg2))

motor.move_relative(angle_to_steps(360), callback=callback, args=("Finished Moving", "Turned 360 Degree"))

API Overview

class Motor (bus, address, axis)

move_absolute (position, callback=None, args=(), kwargs={})

Move the motor to the specified absolute position. Call callback function with *args and **kwargs when position is reached. (callback is optional).

move_relative (offset, callback=None, args=(), kwargs={})

Move the motor by the specified offset relative to current position. Call callback function with *args and **kwargs when position is reached. (callback is optional).

reference_search (rfs_type)

Start a reference search routine to locate limit switches.

rotate_left (velocity)

Rotate the motor left-wards at the specified velocity.

rotate_right (velocity)

Rotate the motor right-wards at the specified velocity.

run_command (cmd)

Execute a predefined user subroutine written to TMCM module firmware

send (cmd, type, motorbank, value)

Send a raw TMCL command to the motor.

stop ()

Stop the motor