Since I’m still waiting for the hardware to arrive, I thought I’d try and hook up one of the stepper motors to the electronics, and try and get it to spin. Easy enough little task.

So I hooked up the power supply to the board, taking extreme care to make sure I get the polarity right on the cable. I then hooked up the motor to the extruder port, and then the electronics to the computer. I then put on one of the toothed gears on the motors, so that its movement would be clear.

I then fired up pronterface using my little script, connected to the electronics, and hit ‘extrude’.

‘hmm’ went the motor, but with no movement. That seemed a little strange. I tried extruding a larger amount. Still no luck.

I went through various alternatives, plugging in a different motor, trying a different axis, even adjusting the potentiometers on the stepper motor drivers. No luck. With nothing else I could think of, I went to the reprap IRC channel, where there where many willing helpers with suggestions. Most of them suggested ideas that I had already thought of.

One IRC-er suggested that the problem was that I was missing jumpers on the RAMPS shield board. To check, I pried up the stepper motor drivers and had a look. No jumpers! With no jumpers in place, the board was trying to do full stepping, rather than 1/16th stepping.

Cursing Auzze under my breath, I shot him a quick email, letting him know that I was short 12 jumpers. He was extremely apologetic, and promised to quickly throw some in the post.

Hopefully the jumpers will fix the problem, and the motor will spin on command.