The M1XEP connects to the J4 RS232 Serial Port on the M1 and the M1XSLC connects to the M1 Data Bus. You can have both connected at the same time.
The M1XEP connects to the J4 RS232 Serial Port on the M1 and the M1XSLC connects to the M1 Data Bus. You can have both connected at the same time.