Hello CNC-knowledgeable folks,
I'm looking for an inexpensive solution to transfer long programs to my "new" toy, a very old Bridgeport CNC mill with BOSS 5 control. It was broken when I bought it, but some new transistors for the stepper drives made the mill work again.
The problem is that the control only has 8 KB of memory, so the best solution would be to drip feed the long programs into it somehow. Unfortunately the RS-232 port in this machine does not use any handshaking, but I understand that this could be overcome using the (parallel) tape reader interface, like with a separate BTR card. Obviously some DNC software packages can be configured to use the PC parallel port for this BTR emulation mode.
Has anyone written any simple program that just acts like a tape reader and feeds the control one line at a time when needed?
I'll be retrofitting this machine with a modern PC control (Mach2) quite soon, hopefully using even the original stepper drives, but I would like to use the original control for some time first and make some chips and parts before I dig into the electronic internals of the B'port. That's why I would like to stick with very simple and inexpensive solutions for DNC. No bells and whistles are needed, just the drip feeding function.
Of course an adapter/optoisolator card would probably be needed to connect the parallel port to the tape reader, but it won't be difficult to build. The problem is that I'm not a software guy, so writing the as-simple-as-possible program for this use is not easy for me...
I'd be grateful for any info on using the BOSS 5 control with drip feed from a PC.
Thanks,
Hobbie