J1 and J2 on the M1 Main Board are the same connection points as the M1 RS485 Green Terminal Block. J1 and J2 were intended as temporary connections for bench testing. We would suggest hardwiring to the RS485 Green Terminal for a more secure connection but you can use the J1/J2 if you’d like. When the M1DBH is connected to the Green Terminal Block and you have the M1XRFTWM connected to J1 this is basically 2 Home Runs.