I'm currently working on repairing a box-moving robot, which uses a CNC Mitsubishi Meldas M64 to control it's movements.
As I've seen around here, my initial problem was quite typical. The Lithium backup battery went down, and therefore a large number of programs and parameters was lost.
I spent three days in learning how to back-up the remaining data, formatting, and reinstalling everything via RS232 serial communication. (I used the Hercules software, a regular multi-communications one).

My problem is this:
While making the above mentioned operations (format, backup,etc.) I used the original configuration for IN/OUT devices: Port 0, Device:0 (Both in Outputting and Inputing data).
Then, I accidentaly changed the port number to 2. Since then, It was impossible for me to establish communication again.
Whenever I try to set the port to 0 again, I get the code: "E02 - Data Over", meaning I'm trying to set an out-of-range parameter.
Does anybody know how to reset the port back to 0?
Do I need to format everything again?
The problem is, that if I choose to format and the ports remain at 2, then I'll be no longer able to load the programs again...

Thanks in advance for taking the time to read my post.
Regards

Martín