Simplex 4020 Terminal Connection

I have a Simplex 4020. I’m not looking to get into the program and make any alterations, but I am trying to terminal in so I can record my test session.

I’m fairly certain the P3 is where I make the connection, but I’m not sure the proper cable to be using. Additionally I can’t remember the com port settings.

Does anyone have any tips/tricks to accomplish this?

Thanks!

The service port is on the front under the display in the little section that the pcb is visible, you can plug a IDC10 pin connector in there. Simplex has a specific pinout so you could either buy a cable or make your own. The Pinout is as follows:

DB9 pin 2 (RX) to IDC10F pin 2 (TX)
DB9 pin 4 (DTR) to IDC10F pin 6 (DSR)
DB9 pin 5 (GND) to IDC10F pin 9 (GND)
DB9 pin 3 (TX) to IDC10F pin 10 (RX)