help wrt UUCP between 3B1 OBM and TB

Bruce Lilly bruce at balilly
Sun May 5 22:12:56 AEST 1991

In article <1991May4.210605.28387 at sceard.Sceard.COM> mrm at Sceard.COM (M.R.Murphy) writes:
>I've a friend with a 3B1 using OBM to attempt UUCP connection
>to two systems, each with a TB (one TB+, one 2500). The TB+
>system is HDB, locked interface speed 9600baud, hardware flow
>control. The TB2500 is HDB, locked interface speed 19.2Kbaud,
>hardware flow control. [ ... ]

This is a well-known problem with Telebit modems (at least the TB+) when
operated with the interface speed locked. The Telebit puts out a
non-standard signal, which causes the 3B1's built-in modem to receive
garbage (the 3B1's OBM is rather intolerant of non-standard signals).
Telebit refers to this bug as "bit-shaving".

If you turn on UUCP debugging, you'll see that the first couple of dozen
characters are received OK, then only garbage is received. You can also
verify this using cu.

Your options are:
1)	don't operate the Telebit's with interface speed locked
2)	try to get Telebit to fix the problem (1-800-TEL-EBIT) (good luck)
3)	trade in the Telebits for another brand of modem
4)	use an external modem on the 3B1 which will accept the Telebit's
	non-standard timing

Unfortunately, if you don't have control of the systems being dialed into,
options 1,2, and 3, which are various attempts to solve the problem at the
source, are not available.
	Bruce Lilly		blilly!balilly!bruce at sonyd1.Broadcast.Sony.COM

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