Help with prusa i3 electronics

I have pretty much finished building my prusa i3. Im trying to wire my stepper motors but am a little confused. Does 1a on the ramps mean a or a- on the stepper? Also, where is the best guide for setting up marlin firmware on the printer? I have been using all different guides but can't seem to get it running. I have the lcd and sd add on but no matter what I do, the lcd will only display black squares.

Thanks for the help!

Edited 1 time(s). Last edit at 08/04/2014 10:21AM by Nitrosport.

Quote
Nitrosport
I have pretty much finished building my prusa i3. Im trying to wire my stepper motors but am a little confused. Does 1a on the ramps mean a or a- on the stepper? Also, where is the best guide for setting up marlin firmware on the printer? I have been using all different guides but can't seem to get it running. I have the lcd and sd add on but no matter what I do, the lcd will only display black squares.

Thanks for the help!

1A - 1B are one coil, wire accordingly, sign does not matter. 2A - 2B are the other coil, wire the same as coil one.

A+ and A- are likely the same coil so they would both be wired to 1 but check the datasheet. LCD will not work without being defined in the firmware.

on my stepper motor the motor specified a.b.c.d and Ramps called for a1,a2,b1,b2 format , with my stepper the pairs were a&c and c&d and also a=a1 b=b1 c= a2 and d=b2 so looking at your motor the 1st wire goes with the 3rd and the 2nd with the 4th.

also you may need to reverse polarity
instead of 2b-2a-1a-1b (specified on Ramps)
you make it 1b-1a-2a-2b (reversed of original)

Use a multi-meter on the wires to find pairs. Very low or no resistance/short will show a pair, open circuit won't. Then wiring to the RAMPS put pairs next to each other on the 4 pin connector.

As already mentioned you need to enable a line in the Configuration.h to get the LCD working (and save/upload to Arduino)

Steve