In my effort to get the SeeMeCNC H1 resurrected, I’ve been troubleshooting my Printrboard that I’m using as the controller.  The current firmware on the board assumes you have end-stops.  Since end-stops are normally closed, if they aren’t connected the board things you’ve hit the end of travel and stops any commands.  So I hooked up the end-stops (although not mounted) and they all work except for the Y-axis.  I found that when I hooked that up, the board wouldn’t properly boot and I couldn’t connect from Repetier.  A large amount of googling finally lead me to a problem with Rev D of the Printrboard.

Lincomatic’s Blog has a page about his version of Marlin built for the Printboard.  He mentions that he doesn’t use end-stops and some of the comments pointed out the EXACT same problem I’m having.  The answer it seems is related to shared pins with the SD Card reader.  You can either disable the SD card reader, or recompile the firmware to utilize the (yet unused) E-STOP pins instead of the Y-STOP pins for the Y-axis end-stop.

Next task is recompiling the firmware for Printrboard and uploading it with the changes.

#define Y_MIN_PIN 20
to:
#define Y_MIN_PIN 37