Machine is a zonestar - Prusa clone. Machine was working fine, but the print lost adherence to the board so I stopped the print using the 'stop print' option under the SD card menu.

When I restarted the machine, it started normally, with a normal display. The bed and head temperatures came up normally. But when the machine zeroed all its axes, it failed to stop on the x axis, continuing to grind away at the belt until I pulled the plug.

I confirmed the behavior - it'll do it every time. I reset the board using the on-board reset switch, but that had no effect. I checked the switch with an ohm meter, and it's working correctly. I checked the carriage travel, and the switch does indeed trigger when the carriage reaches the stop. I homed the y and z axes through software, and they both homed normally and stopped. But when I tried to home the x axis through software, it ignored the limit switch and continued to grind away until I pulled the plug.

Basically, the board isn't paying attention to the X axis limit switch.
Phone Ringtone

Anybody got any ideas?