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[Drools]

I have a EasyDriver from Sparkfun, it is a small stepper driver. Good for a nema17 which is what I want to use with it. I'm looking for some code for an Atmega48 series uC to generate the step signal. All I can find is code for the Arduino but I want to use C in AvrStudio. (my Arduino is broken)
I could also use a 555 timer if someone has a circuit diagram for that.
Thanks for the help.
Happy New Year!

[Drools]

I just thinking here but is the step signal similar to PWM? or maybe the same as PWM?
I know the direction signal is just a logic high/low.

[irving2008]

Step signal is just a pulse, typically about 5 - 10uS or so wide, pulse rate depends on how fast you want the motor to turn. Generally for fast pulse rates you need some sort of ramp up (accelerate) and ramp down (decelerate) approach to avoid missing steps due to mechanical inertia.

[Drools]

So the pulse frequency varies not the width as in PWM. I think I can program a pulse from the AVR using a timer. Thanks!

[mmcp42]

I'm using the same board (3 of them) but driven from an Arduino Uno

If you like I can post the code (what I rote) that interprets gcode directly to give step and direction control for all 3 axes

No acceleration though

[Drools]

Sure please.
My Arduino does not communicate with the PC, the serial interface does not work. (not even with a USB to Serial converter).
Maybe I can brain storm converting the Arduino code to GCC.

[mmcp42]

without a working serial interface you are doomed!

[Drools]

I was thinking of going back to using AVRStudio4 and my AVRISP mkii and program my chip that way.

[Drools]

mmcp42, how hot does your easydriver get?
What voltage are you using?
I have mine working with a nema17 motor with a coil resistance of 5.3ohms@12VDC.
The chip gets fairly hot. I was using a nema17 motor with a coil resistance of 15.1ohms but the motor got fairly hot along with the chip.

[mmcp42]

I'm using a stepper from an Epson scanner
about half the size of a NEMA17 as far as I can judge

One EasyDriver gets almost too hot to touch, but keeps soldiering on!
that's the Z-axis
x and y are cold even when busily stepping away!

it may be that Z need to hold itself stationary more than x an y

ISTR it has over-temp detection so will shut down if fertiliser gets too close to aircon

oh and I have it so that the card is disabled when the axis is stationary, that keeps it a lot cooler

oh and I'm using a 9v wall-wart

motors are stone-cold