knudsen@ihnss.UUCP (03/13/84)
(To Richard Bisbey, on ARPA, but of general interest on Coco RS232 Pak) No, I got no schematics with it, but complete sof specs on how to set baud rates, parity, etc etc, even send breaks. It's very complete RS232 interface, except does not have Ring Detect as needed for auto-answer, a major omission for some uses. Pak also contains a ROM (at $C000 as usual) with some decent terminal software. Of course you can't run that code while in Disk Basic, BUT your own code can still access the fully-decoded device regs starting at $FF68 (I think). I have lots of UARTs and such parts around and was about to build my own RS232 as you suggest. But the firmware was worth the $80 to let me use the Coco as a CRT terminal. Unfortunately it can upload/download only BASIC and machine code files, not raw text. Would like to hear what protocol it uses; it's intended to talk to another copy of itself, not a mainframe. ANYBODY GOT THAT PROTOCOL? As a terminal, you supposedly have same cursor-control functions as a DEC VT-52. In that case, I have a termcap for Un*x. Richard, if you just want RTTY/packet radio interface with all your own code, by all means roll your own. Consider putting FIFO buffers in it too; OS-9 could sure use a receive buffer so you don't lose chars while disk is running. Finally, you mentioned 6522. I'd appreciate a spec sheet on that chip, as there is a conspiracy of silence among its few makers. mike k