We have a very old Hitachi Seiki machine with an equally old Fanuc controller. This is just used for piecework / small batches. It has a very small amount of memory and we do a variety of parts, so we can't really store programs in the controller.
Is there a unit/system that would plug into the RS232 that would have a usb input that would allow the use of a thumb drive?
a better way is to use a pocket PC. they are cheap and work really well. I have one here that I use for serial transfer. just be sure to buy one that has a serial port.