I had the printer up and almost running about a week ago but one of my stepper drivers was dead. I replaced it and when i turned the printer back on the motors only run in one direction. I am in pronterface for Mac. So for the Z axis I can move it up with no problem but if try to move it down it just makes a humming sound and doesn't move. After i hit the done button and the motors stop humming if I hit the UP button the motors just hum like they do when I hit down. The only way to get them to move back up is that I have to reset the printer. This happens on all the axis and the extruder. I am using the Sprinter firmware on it and I have re-uploaded all the code and that didn't help. I have also tried changing the variable resistor on it but it doesn't seem to help at all. I am using a Sanguino 1.3A with Stepstick A4988. The hot plate and the extruder both heat up fine and the end stops do stop the motors when they hit them.

DON'T DOUBLE POST - answered this in the 'other' thread.

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Bob Morrison
Wörth am Rhein, Germany
"Luke, use the source!"
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