Found the problem...I long while back I upgraded the stock stepper drivers to take advantage of 1/32 steps. That and trying to drive the z axis at too high a speed were crashing the board when the Viki display was also enabled. I retrofitted my original driver chip for the Z Axis and slowed the max feedrate for the Z Axis in Marlin and now the printer will home with the Viki controller enabled wiby TDecker - Controllers
Viktor, I doubt the limit switch is to blame. The hard reset happens well before the carriage gets anywhere near the limit switch. (Additionally, the limit switches (and their harnesses) haven't been touched since I got the machine 4 years ago.) For instance, the carriage can be at 300mm (if I've just swapped out nozzles), and if I home (with the display enabled) the Z axis, the carriage will loby TDecker - Controllers
I have a I2C Viki LCD/Encoder connected to a Megatronics 2 board on my Glacier Summit. I am running the latest release of Marlin. As configured, the display and the encoder work as they should. However, if I try to home the Z axis either via the Viki controller OR Repetier, the printer will start to home for maybe 5mm and then the megatronics board will reset. I've tried disabling the Viki via tby TDecker - Controllers