BSKENDIG@pucc.Princeton.EDU (Brian Scott Kendig) (04/25/89)
I have a great little project that I've been trying to accomplish for quite some time, but as yet I haven't any luck whatsoever. Here's the scenario: I have a Commodore 128 home computer, and an MPS1000 dot- matrix printer to go with it. The printer is hooked up to the computer through a Xetec Super Graphix interface, which makes the printer think it's an IBM5152+ printer and comform to Epson control codes at 80 dots per inch. I recently got a Macintosh SE computer. At school I can type up papers on it, save them to floppy, and bring the floppy over to a nearby LaserWriter to print them. So right now, I don't need a printer for it. But it would be awfully nice to be able to print out rough copies of things out at home over the summer! Hooking the Mac directly to the printer is out of the question - I could buy the necessary cabling, but that's too easy. I'd much rather try to hook the Mac to the Commodore and print *through* it. Theoretically, this should work: I can hook the printer port of the Mac up to my RS232 interface on the Commodore, have the C128 translate the incoming ImageWriter control codes to Epson codes, and send *that* to the MPS1000. In practice, it doesn't work. I wrote a short program on the 128 that echoes to the screen anything that comes in from the Mac, then I had the Mac "print" a small MacPaint file. I figured that I would see the ImageWriter control codes, and from them be able to figure out what the picture looked like. After all, that's all the real ImageWriter does, isn't it? I only get meaningful data when I tell the computers to communicate at 2400 baud - the C128 can't handle anything faster, and slower speeds give me garbage. (How does the ImageWriter tell its baud rate setting to the computer, anyway?) But the bytes I get do not match what I *should* be getting according to the ImageWriter manual. In fact, I can't make any sense of the data whatsoever, although it *looks* like it should be making sense. (It's not entirely random.) If anyone has any ideas whatsoever on what I'm doing wrong, how I could do it *right*, or how I could accomplish my desired end by any other means, please drop me a line. Or, if you just feel like chatting on the state of the world today, drop me a line. Or even if you have nothing better to do - drop me a line. I'm bored (or else I wouldn't be trying to figure out stupid configurations like this). Brian Scott Kendig Send all replies to Princeton University '92 bskendig@escher.Princeton.EDU Currently engaged in the eternal search for a computer that Quotes? You've got to be kidding! doesn't crash or get viruses. I don't quote people - *they* quote *me*.
rcbamw@eutrc3.UUCP (m.waucomont) (04/26/89)
In article <8061@pucc.Princeton.EDU> BSKENDIG@pucc.Princeton.EDU writes: >Theoretically, this should work: I can hook the printer port of the Mac up to >my RS232 interface on the Commodore, have the C128 translate the incoming >ImageWriter control codes to Epson codes, and send *that* to the MPS1000. Correct! >I only get meaningful data when I tell the computers to communicate at 2400 >baud - the C128 can't handle anything faster, ...... And that's your problem. Transferrate is 9600 baud, using 1 startbit and one stop bit.... M. 'Mikki' Waucomont