mdapoz@hybrid.UUCP (Mark Dapoz) (05/28/90)
In article <1990May23.183735.9239@sonyd1.uucp> bruce@sonyd1.uucp (Bruce Lilly) writes: >It seems that the built-in modem in the AT&T 3B1 (a.k.a. 7300) has some >problems when communicating with Telebit modems at 1200 baud. The >problem occurs when the OBM calls out to a Telebit which is set to >provide the PEP answer tones first. The symptom is a sequence of >correctly received characters (about 20) followed by gibberish. This problem only occurs when talking to a telebit which has locked the interface speed (ie. S51 = [0-5]). I think the problem was that one of the modems (the telebit I believe) is cutting the stop bits a little bit short of what the other expects, and as a result you get garbage. For some reason the problem disappears when you get the telebit to autobaud the interface. >At this point, I suspect either a hardware problem, or a problem with the >driver for the OBM (assuming it hasn't changed between 3.51 and 3.51m). As you've found out, the OBM is very picky with what it's communicating with. Do yourself a favour and pick up a cheap 2400 baud modem and hook it up to the serial port. >Has anybody else experienced this problem, and if so, are there any >workarounds (short of using 300 baud, which does work) or bug fixes? See above, I got it to work that way but I don't guaranatee that it'll still work since I don't use the OBM and my telebit now has V5 roms. -- Managing a software development team | Mark Dapoz is a lot like being on the psychiatric | mdapoz%hybrid@cs.toronto.edu ward. -Mitch Kapor, San Jose Mercury | ...uunet!mnetor!hybrid!mdapoz