File content as of revision 0:12be56dc6182:

#include "mbed.h"
#include "StepperDriver.h"

StepperDriver::StepperDriver(PinName outputPin, PinName directionPin) : output(outputPin), direction(directionPin) {
    currentPosition = previousPosition = desiredPosition = 0;
    maxPosition = 500;
    minPosition = 0;
    homePosition = (maxPosition - minPosition) / 2;
}

void StepperDriver::setPosition(uint32_t position) {
    if (position >= minPosition && position <= maxPosition) {
        desiredPosition = position;
    }
    if (desiredPosition != currentPosition && !isTickerAttached) {
        attachTicker();
    }
}

void StepperDriver::update() {
    if (desiredPosition > currentPosition) {
        direction = 1;
        currentPosition++;
        generateImpulse();
    } else if (desiredPosition < currentPosition) {
        direction = 0;
        currentPosition--;
        generateImpulse();
    } else {
        detachTicker();
    }
    previousPosition = currentPosition;
}

void StepperDriver::attachTicker() {
    ticker.attach(this, &StepperDriver::update, 4e-3);
    isTickerAttached = true;
}

void StepperDriver::detachTicker() {
    ticker.detach();
    isTickerAttached = false;
}

void StepperDriver::generateImpulse() {
    output = 1;
    timeout.attach(this, &StepperDriver::turnOutputOff, 100e-6);
}

void StepperDriver::turnOutputOff() {
    output = 0;
}