Okay.. This happens to me last day .. Mach3 freezes and error triggered 9991. G540 went into red light mode ... I resolved the problem:
1- Deleted all the unnecessary plugins from Mach3 plug-in folders. Do you use any pendant?
2- Do you use any special macro in the Gcode?
3- I will suggest you to fresh install Mach3 version. I am using Mach3 version 3.43.062 successfully.
4- Do you have any limit/home switches installed on machine?
5- Did you add any device or implemented any changes after that trouble-free 12Hrs run?
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