[comp.unix.xenix] advice on modems wanted please

john@bby-bc.UUCP (john) (09/29/87)

 I have just spent a couple of disappointing days trying to get a
 2400baud modem working with my Microport system.  Aside from problems
 which seem outright bugs with the modem (e.g. didn't always go on hook
 when the callers carrier dropped, occasionally thought it was recieving
 data even though there was no connection, etc, etc, ETC!) the major
 problem seemed to be that right after making a connection with an
 incoming call it would drop CD while it transmitted it's connect
 message and this would cause getty to die.  For obvious reasons I
 don't want to leave CD forced permanently on.

 Therefore I am soliciting suggestions as to good (preferably inexpensive)
 modems to use.  I am partial to external units.  I would particularily
 appreciate hearing from other Microport users as to which modems they
 have found work well.  Thanks in advance for any infomation.....

	john

 ....ubc-vision!fornax!bby-bc!john

root@hobbes.UUCP (John Plocher) (10/04/87)

+---- john@bby-bc.UUCP (john) writes in <163@bby-bc.UUCP> ----
| 
|  I have just spent a couple of disappointing days trying to get a
|  2400baud modem working with my Microport system.
|  						       ... the major
|  problem seemed to be that right after making a connection with an
|  incoming call it would drop CD while it transmitted it's connect
|  message and this would cause getty to die.
+----

Try turning the modem's local echo off.  If you are using the new dialer
(state machine in /usr/lib/uucp/dialinfo) it gets confused when the modem
echos the "ATDTxxx-xxxx".  Either that, or expand the dialinfo file to handle
the echo'd stuff.
Here is the dialinfo file I use for a USR 212A (1200 baud):


##############################################################
#       Dialinfo - Dialer procedure definitions              #
##############################################################

usr212A,
	retry=20,
	s0=P1 M"AT E0 M0 S0=6 Q0\r" [OK]1 [in:]4 [IN:]4 [rd:]4 [RD:]4 S10 T3,
	s1=M"AT DT%N\r" [CONNECT]10 [NO CARRIER]2 S60 T3,
	s2=D1 R3 G0,
	s3=D1 R10 G0,
	s4=D1 R5 G0,
	s10=C1 G+,

The s0 line ("AT E0...") turns both local echo and the speaker off, sets
the autoanswer for the 6th ring (the line is primarily a voice line) and
does something with the "Q" command which I forget at the moment :-).  After
getting an "OK" it goes to state 1, otherwise ("in"...) it assumes it is 
already connected to a Unix port and drops carrier and repeats.
State 1 dials the number (%N) and waits for either the "CONNECT" or the
"NO CARRIER" message.

If instead of getting "CONNECT" it got "AT DTxxx-xxxx" it wouldn't know what
to do!

Hope this helps.

PS:  This dialer seems to have been posted to Usenet at one time, but it 
IS NOT the one found in Volume 3 of the comp.sources archives at Purdue.
If anyone knows where I can find source for it I'd appreciate it.
-- 
John Plocher uwvax!geowhiz!uwspan!plocher  plocher%uwspan.UUCP@uwvax.CS.WISC.EDU