heiser@tdw201.ed.ray.com (08/29/90)
I have an old, old, old USR HST 9600. It is the original type that
makes loud clicking noises when it dials, and has the 300 baud backchannel.
I am attempting to use it with my new Esix (unix sysVr3) system.
It seems that I can get it to either work at 9600 baud, or at a lower
speed, but not both. I have tried it both with the speed locked
and with it unlocked. The problem I'm working on right now is to get
it to accept either user or uucp inbound calls. When the speed is
locked at 9600, a 9600 can connect just fine -- but a 2400 caller gets
only garbage. When the speed is not locked, 2400 callers can get it
(usually, but not always), but 9600 callers have garbage.
I know this isn't the optimal modem for this application .. but I can't
afford a Telebit right now (and they have big problems with low-speed
modems trying to connect). What I'd like to find out is will this old
HST work at all for this application? Am I wasting my time fiddling with
it? I understand that the transmission rate is best when the speed is
locked .. but am willing to forgo optimal speed to just get it to work
at both 9600 and 2400.
various things to consider ...
gettydefs: should it be allowed to cycle, or should it be locked in to
one speed with the modem handling the different call-in speeds?
inittab: At what speed should uugetty init the modem?
register settings on hst: I've used the modem on a dos bbs and it worked
fine (but ONLY with the speed NOT locked) ... I never have had success
with it locked.
Any suggestions would be welcome. If it won't work, I'll just lock it
at 2400 and forget about 9600-HST ... and get a Telebit as soon as I
can (anyone have one for sale at a good price?)
--
Bill Heiser
Work: heiser@tdw201.ed.ray.com
{decuac,necntc,uunet}!rayssd!tdw201!heiser
Home: Bill.Heiser@f240.n322.z1.fidonet.org (Fidonet 1:322/240)
The Think_Tank BBS (508)655-3848 1200/2400/9600-HST
Other: 75106.2332@compuserve.com
Other: heiser@world.std.com (Public Access Unix)ralphs@halcyon.wa.com (Ralph Sims) (08/30/90)
heiser@tdw201.ed.ray.com writes: > I know this isn't the optimal modem for this application .. but I can't > afford a Telebit right now (and they have big problems with low-speed > modems trying to connect). Ahem. I believe it's the low-speed modems that have the problems. I find that some EVEREX 1200's, PROMETHEII (whatever the plural is of PROMETHEUS), and AVATEK's generally have difficulties. A few things can make life a bit easier. If the Telebit answers with its PEP tones first, some modems get confused by the sequence and disconnect; this can be overcome by having the calling modem use S9=20 and S10=20 (*). These settings hold them online for 20 seconds when carrier drops, which may be what they think is happening. setting S7 in excess of 45 seems to help at times. USR's (and maybe some others) may have a register that allows the modem to detect a 'voice' call. Don't believe it! The Telebit's PEP tones are far from a 'voice' (unless you're Bill the Cat) and those that use this scheme will hang up on it (maybe an X7 register for the USR HST?). This 'feature' should be against the law :-) . Aside from the strange answering sequences, another thing gets in the way: MNP. Yep, that thing that we like to use for error-correction at times. Again, referencing the above-mentioned modems, the MNP 'handshake' routine can throw things for a loop. Turn MNP off for low-speed connects, especially if your users are mainly interested in reading text and not file transfers. I have a ZOOM PC2400 that performs flawlessly when I do these things and craps out when I don't. Data communications is a black art. > Any suggestions would be welcome. If it won't work, I'll just lock it > at 2400 and forget about 9600-HST ... and get a Telebit as soon as I > can (anyone have one for sale at a good price?) Contact uunet for their prices--I don't think many can beat them. Larry Snyder (nstar) and I tried HST's for UUCP and I gave it up as a lost cause (although U.S. Sprint loved it!). ~345cps was not my idea of a good time, especially at ~US$6.00/hr. with a backbone feed. (*) I also use these settings on the Telebit to take care of things like call-waiting on the other end, etc. This trick also does a good job of defeating call-waiting on outdial, but both ends need to co-operate. -- No matter who you elect, the Government still gets in.