Hayes modem on HDB UUCP?

wescott at sauron.UUCP wescott at sauron.UUCP
Sat Aug 16 05:01:58 AEST 1986


The Hayes modems don't like to get echos from their connect messages.  There
are several approaches that I could recommend, none of which are completely 
satisfactory.  These suggestions apply to SysV only (in fact, the HDB uugetty
claims not to work with BSD).

	#1. Set up the modems for quiet operation, disabling result codes and
	    echo while waiting for activity.  Then modify the dial script to
	    enable result codes and perhaps turn on echo.  I have not tried
	    this approach.  It may not work for Hayes 1200 modems because this
	    relies upon the cycling of DTR to cause the modem to "reset" back
	    to the non-echo, no-result-code state.  The Hayes 2400 baud modems
	    should work OK.

	#2. Modify uugetty.  Add an optional digit sequence to the -r option
	    which tells uugetty how long to wait after receiving its first 
	    input before doing anything.  This has several problems but does
	    work.  uugetty has been changed here to sleep the specified number
	    of seconds and then to flush input and then to wait for a char-
	    acter.  This can confuse uucico's that are calling out because
	    a number of characters may not get echoed back to uucico during
	    a dial sequence.

	#3. Modify uucico and the tty drivers.  Another change that I am ex-
	    perimenting with is to permit uucico to issue dial sequences in
	    clocal mode (no DSR/DCD required) and then to wait for carrier
	    after completing the dial sequences.  The hacks include adding
	    a flags to the Devices file to indicate when clocal is to be
	    used and when to wait for DSR/DTR to be turned on.  Then the
	    drivers need to be modified so that a uugetty on the same line
	    (not using the -r option) will have its open complete when DCD
	    does come up. (This was discussed earlier, but not wrt uugetty).

-- 
	-Mike Wescott
	 ncrcae!wescott



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