Salsa:
You need a computer with serial communication via RS232, a suitable communication program for the computer, and a cable from the computer to the CNC machine.
On the HAAS there are the two connectors you refer to. If cables are connected properly inside HAAS, then COM 1 would be the connector to which you connect your cable to the computer.
If you have a computer with a 9 pin RS232 serial connector, then between the computer and HAAS connect pin 2 to 2, 3 to 3, and 5 on the 9 pin to 7 on the 25 pin. If your cable has a shield then connect the shield to pin 1 on the HAAS end. With this cabling you must use software handshake or Xmodem. Ignore all other pins. To make it clear pin 5 on the computer to pin 7 on HAAS.
Your cable length will determine maximum baud rate.
As a starter I suggest the following RS232 parameter settings --- 9600 baud, 7 data bits, even parity, 1 stop bit, and XON/XOFF for handshake.
You can try Hyper Terminal which is part of Windows for your first try at communication. Also start by sending from HAAS to the computer.
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