[net.micro] Hayes Smartmodem

mcm (12/16/82)

I have been using a Hayes Smartmodem for our dialin/dialout line
since we were connected to USENET (around March, I think.)  In
October we switched to the 1200/300 model (7 months at 300 baud!)
I have made mods to cu and uucico, and have had no trouble with the
modem.  I did have trouble when I switched from the 300 to 1200/300,
but the new code will work on the 300 only with no problems.

After much experimenting, I found the modem worked best if it was
reset when you are through using it.  Reset the modem by dropping
DTR to it, then sending the ATZ code.  Our modem is set so it never
echos return codes.  This causes a slight problem with cu, but uucico
doesn't mind.  I might change cu to set the modem into "return verbose
codes" state before dialing, so I can tell if the phone is busy.  This
will not affect uucico, as cu resets the modem (ATZ) to its power-up
condition.  I have found that if you send garbage to the modem
while it is in the command state, the modem repeats the last command
it received.  This caused a major headache while I has working on
uucico, as the last command I was sending was to dial the phone!

Although I wrote a dialout() routine for uucico, it is possible to
control the modem with just the L.sys line.  We did that here for
a few weeks before I decided to write the dialout() code.

	Mike Mitchell
	decvax!duke!mcnc!ikonas!mcm