On Saturday, September 20, 2014 8:25:00 AM UTC-7, Karl Townsend wrote:

My son has his old matsuura up and running. Its pre LAN connection,
needs the RS232 port to download CNC programs.

PinOuts.ru should have the wiring specs.

If you use an RS-232 to USB adapter, some don't use real RS-232 voltage levels, like -3V to -15V for a logical true and +3V to +15V for a logical false, but use 0V for a true, and that doesn't work with some equipment. I'd expect adapters based on Cypress chips to be OK, but apparently the first choice is an FTDI brand chip, and they have driver software for every operating system. I think StarTech brand adapters are still good, but Cables Unlimited was also selling FTDI adapters that worked well.