curta

curta

Simulator for the Curta Type I, a mechanical calculator manufactured between 1947 and 1972.

Install

npm install --save curta

Usage

To compute the multiplication of 27 × 4:

var Curta = require("curta");
var curta = new Curta();

// Load 27 in the Setting Register
curta.setRegister(1, 7);
curta.setRegister(2, 2);

// Turn the handle 4 times
curta.turn(4);

curta.result(); // => 108
curta.readCounter(); // => 4

Just as we would on a normal Curta.

More advanced, 1024 × 512:

var curta = new Curta();

curta.setRegister(4, 1);
curta.setRegister(2, 2);
curta.setRegister(1, 4);

curta.setCarriage(3);
curta.turn(5);

curta.setCarriage(2);
curta.turn();

curta.setCarriage(1);
curta.turn(2);

curta.result(); // => 524288
curta.readCounter(); // => 512

API

var curta = new Curta()

Creates a zeroed-out Curta state.

curta.turn([n])

Turns the crank once, or if a number is passed in, that number of times.

curta.liftCrank()

Lifts the crank, so that each turn will subtract from the counter and result instead of adding to them.

curta.lowerCrank()

Lowers the crank, putting the calculator back in addition mode.

curta.clearCounting()

Clears the counting registers.

curta.clearResult()

Clears the result registers.

curta.clear()

Clears both the counting and result registers.

curta.readCarriage()

Reads the carriage setting, which determines the exponent of 10 we add to the counter.

curta.setCarriage(position)

Sets the carriage position to a value between 1 and 6.

curta.readSetting([register])

Reads the value of the setting registers. If a given register is passed in (a number between 1 and 11), it reads the value of that particular register.

curta.readCounter([register])

Reads the value of the counting registers.

curta.readResult([register])

Reads the value of the result registers.

curta.setRegister(register, value)

Sets the given setting register to a particular value.

Testing

npm install
npm test

License

MIT © Jordan Scales