Hello, please help and advice.  I'm installing a push button to start and push button stop the program, (rather than clicking a mouse or the key board). I'm using a PLC unit to be the slave to mach3. Is there a way that the Mach3 system can to send a signal to the plc, notifying that machine is at X0,Y0,Z0, ie. Home position and is ready to start running the program?
thank you in advance.

You need to read up on MODBUS assuming your PLC has that function