pete@ddsw1.UUCP (Peter Franks) (09/20/88)
I have common problem -- difficulty in setting up a bi-directional dialup.
I'm using an AT clone and an Arnet Smartport card with 8 ports under
Microport System V/AT using Microport's BNU (AKA HDB).
The problem is when the modem's responses are turned on, I get (I believe
it's called) a 'deadly embrace'. If the responses are turned off (via
dipswitch) the port works fine as a dialup, but I can't get it to dial out
('cause of no responses). If I have the Dialers script turn on the
responses, they will stay on unless the DTR drop at the uugetty respawn
resets the modem to the 'dipswitch' mode. Thus, my question is:
What modems will reset to the dipswitch (or EEPROM)
parameters on a DTR drop?
I have a MultiTech 224AH and a USR Courier 2400, neither of which do (I
don't think). I'm planning on getting a couple of TrailBlazers, which I
KNOW will do it, but I'd like to know what others will work, and maybe,
what I can do (modifications) to make the ones I have work that way.
Thanks.
--
-------------
Remember:
No matter how obnoxious it gets, you CANNOT execute a device!cdold@starfish.Convergent.COM (Clarence Dold) (09/21/88)
From article <1731@ddsw1.UUCP>, by pete@ddsw1.UUCP (Peter Franks): > What modems will reset to the dipswitch (or EEPROM) > parameters on a DTR drop? The NEC 2400 (sold by Convergent as the DC2400) is supposed to be 'Hayes' compatible. The command AT&D3&W programs it to go back to the CMOS setups when it sees an On to OFF transition on TR. -- Clarence A Dold - cdold@starfish.Convergent.COM (408) 435-5274 ...pyramid!ctnews!mitisft!professo!dold P.O.Box 6685, San Jose, CA 95150-6685
ostroff@oswego.Oswego.EDU (Boyd Ostroff) (09/21/88)
In article <721@starfish.Convergent.COM> cdold@starfish.Convergent.COM (Clarence Dold) writes: >From article <1731@ddsw1.UUCP>, by pete@ddsw1.UUCP (Peter Franks): >> What modems will reset to the dipswitch (or EEPROM) >> parameters on a DTR drop? > The Everex EMAC MD2400 offers several options for action on loss of DTR using the AT&Dx command, where x is a number from 0 to 3 (I think). Basically, you can cause the modem to either totally ignore DTR (&D0); to revert to command mode (&D1); turn off auto-answer and revert to the previous settings, re-enabling auto-answer on the next DTR high (&D2); or completely reset (&D3). It doesn't have any EEPROM :-( ::::::::::::::::::::::::::::::::::::::::: :: Boyd Ostroff, Technical Director :: System Operator, "The CallBoard" :: Department of Theatre, SUNY Oswego :: - Serving the performing arts - :: Internet: ostroff@oswego.Oswego.EDU :: (315) 947-6414 300/1200/2400 baud 8N1 :: Voice: (315) 341-2987 :: UUCP ...sunybcs!oswego!cboard!ostroff :::::::::::::::::::::::::::::::::::::::::
jpr@dasys1.UUCP (Pierre Radley) (09/22/88)
The Practical Peripherals PM2400SA also tracks the DTR, and the command AT&D3&W will cause it (quoting from the manual) to "assume the initializa- tion state if it detects an 'on-to-off' DTR transition." -- Time is nature's way of Jean-Pierre Radley making sure that everything ..!cmcl2!phri!dasys1!jpr doesn't happen all at once. CIS: 76120,1341
ron@topaz.rutgers.edu (Ron Natalie) (09/24/88)
The Anchor 2400E modems seem to be Hayes compatible enough to let the Hayes Interbridge dial it. I've been using one for a couple of months now without a problem. They are under $200 and even come with a power switch and volume control (unusuall feature for most modems). -Ron
robert@pvab.UUCP (Robert Claeson) (09/25/88)
In article <6592@dasys1.UUCP>, jpr@dasys1.UUCP (Pierre Radley) writes: > The Practical Peripherals PM2400SA also tracks the DTR, and the command > AT&D3&W will cause it (quoting from the manual) to "assume the initializa- > tion state if it detects an 'on-to-off' DTR transition." Actually, almost any Hayes-compatible modem will accept this. -- Robert Claeson, ERBE DATA AB, P.O. Box 77, S-175 22 Jarfalla, Sweden Tel: +46 758-202 50 Fax: +46 758-197 20 Email: robert@pvab.se (soon rclaeson@erbe.se)
pete@ddsw1.MCS.COM (Peter Franks) (09/26/88)
In article <318@pvab.UUCP> robert@pvab.UUCP (Robert Claeson) writes: >> [information about Prattical Peripherals modem reseting on DTR drop, >> response to '&' commands, etc.] > >Actually, almost any Hayes-compatible modem will accept this. This is not true!! From what I have seen, MOST Hayes-compatible modems aren't! Oh, they will accept most Hayes 'AT' commands, but they don't have non-volatile memory, and thus won't accept the '&' commands, nor will they reset upon DTR drop. This is why I posted the original article - the modems I have access to don't have non-volatile memory, nor do they reset upon DTR drop. They are the [old version] MultiTech 224AH and a USR Courier 2400 [also old]. I do not know whether the newer versions of those modems have the needed features or not. I appreciate all the answers [via email] that I got, but they all basically said the same thing - use the &D3 command. I would if I could, but I can't, so I won't! So, to reiterate the major question [and to restate it a bit]: What "Hayes compatible" modems have non-volatile memory and will (if desired) reset to the conditions stored in that non-volatile memory upon DTR drop? Thanks again. -- ------------- Remember: No matter how obnoxious it gets, you CANNOT execute a device!
les@chinet.UUCP (Leslie Mikesell) (09/27/88)
In article <318@pvab.UUCP> robert@pvab.UUCP (Robert Claeson) writes: >> The Practical Peripherals PM2400SA also tracks the DTR, and the command >> AT&D3&W will cause it (quoting from the manual) to "assume the initializa- >> tion state if it detects an 'on-to-off' DTR transition." >Actually, almost any Hayes-compatible modem will accept this. But many (most/all?) 2400 baud hayes-compatibles will not drop the line before completing a call if you give a dialing command and then drop DTR. Also, after doing this, the modem has an error message that it will store until DTR is on again, so the next attempt to dial is likely to fail. Do any modems handle this right? Les Mikesell
robert@pvab.UUCP (Robert Claeson) (09/29/88)
In article <6662@chinet.UUCP>, les@chinet.UUCP (Leslie Mikesell) writes: > But many (most/all?) 2400 baud hayes-compatibles will not drop the line > before completing a call if you give a dialing command and then drop > DTR. Also, after doing this, the modem has an error message that it > will store until DTR is on again, so the next attempt to dial is likely > to fail. Do any modems handle this right? My Microcom AX/2424c seems to handle this right. But I haven't tried it much, so I cannot say for sure. BTW, I have the CCITT version of that modem (no Bell protocols). -- Robert Claeson, ERBE DATA AB, P.O. Box 77, S-175 22 Jarfalla, Sweden Tel: +46 758-202 50 Fax: +46 758-197 20 Email: robert@pvab.se (soon rclaeson@erbe.se)
cpt.k9@netmbx.UUCP (Bob George) (10/02/88)
In article <1779@ddsw1.MCS.COM> pete@ddsw1.UUCP (Peter Franks) writes: >So, to reiterate the major question [and to restate it a bit]: > > What "Hayes compatible" modems have non-volatile memory > and will (if desired) reset to the conditions stored in > that non-volatile memory upon DTR drop? > Sorry for coming in on this in the midst of a discussion, but I can say from experience that the Prometheus Promodem 2400G will meet this requirement. I picked one up recently for about $180.00, and it works well. To quote the manual: "AT&D Data Terminal Ready (DTR) options D0 - The Promodem ignores DTR D1 - Assumes command state with on-to-off transition D2 - Modem goes on-hook, assumes command state and disables auto answer with on-to-off transition *D3 - Modem executes initialization routine*" Note: I have no association with Prometheus other than as a satisfied buyer. I hope this is what you're after! Bob -- Bob George, Unter den Eichen 97, 1000 Berlin 45, W. Germany cpt.k9@netmbx.UUCP Tel: (049-030) 832-8319
tboutell@vax1.acs.udel.EDU (Thomas B Boutell) (10/10/88)
That's not quite true. Many Hayes- compatible modems will reset entirely when DTR is toggled, but the correct response is merely to break the connection and go into command mode. The reinitialization is a nuisance which forces most programs to tediously resend any setup commands they had already communicated to the modem after each call. -Tom
pete@ddsw1.MCS.COM (Peter Franks) (10/11/88)
In article <2047@udccvax1.acs.udel.EDU> tboutell@vax1.acs.udel.EDU (Thomas B Boutell) writes: >That's not quite true. Many Hayes- compatible modems will reset entirely What's not quite true?? >when DTR is toggled, but the correct response is merely to break the >connection and go into command mode. The reinitialization is a nuisance >which forces most programs to tediously resend any setup commands they >had already communicated to the modem after each call. > The 'correct response'??? The 'correct response' for who? You, maybe, but not for me!! This entire thread was started to find modems which perform a certain function in order to do a certain job - to reset when DTR is dropped so that they (the modems) can be used on a bi-directional port in a UNIX system. The fact that you find said reinitialization to be a 'nuisance' is one reason that that function is configurable, but it it, in the context of this thread, TOTALLY irrelevant!! -- Remember: No matter how obnoxious it gets, you CANNOT execute a device!
vixie@decwrl.dec.com (Paul Vixie) (10/11/88)
# Many Hayes-compatible modems will reset entirely when DTR is toggled, but # the correct response is merely to break the connection and go into command # mode. Correct? I assure you that getty(8m) does not want to talk to a Hayes modem while in command mode. The "correct" thing in that case is to go into E0Q1, which will often not be the case if UUCICO just got done making an outgoing call. UUCP doesn't usually have a way to reinit the modem to user preferences when a call is complete; it's darned handy if the modem will do it for you. On a Telebit, I can get this behaviour. On a Hayes 1200, I can get it. On a Hayes 2400, I can get most of it. On other modems, I've had some serious problems. The Anchor Signalman XII doesn't even connect DTR to anything internally (hah! solved that one with a reed relay that shut off the power to the modem when DTR was down!). -- Paul Vixie Work: vixie@decwrl.dec.com decwrl!vixie +1 415 853 6600 Play: paul@vixie.sf.ca.us vixie!paul +1 415 864 7013
mhw@wittsend.LBP.HARRIS.COM (Michael H. Warfield) (10/22/88)
In article <2047@udccvax1.acs.udel.EDU> tboutell@vax1.acs.udel.EDU (Thomas B Boutell) writes: >That's not quite true. Many Hayes- compatible modems will reset entirely >when DTR is toggled, but the correct response is merely to break the >connection and go into command mode. The reinitialization is a nuisance >which forces most programs to tediously resend any setup commands they >had already communicated to the modem after each call. Many of these modems (including the real McCoy V series Hayes) have an option on the DTR action (&Dn). A setting of &D3 on most of these modems sets them up to reset on a true to false transition of DTR. That resets it to the settings in the non-volatile memory. All modems at my site are configured this way. This site uses dozens of modems at speeds from 1200 through 9600 baud (including both Hayes 9600 and Telebit Trailblazer). Any register setup commands which are always used should be loaded into non-volatile memory. The ability to reset the modem back to a known state by dropping DTR is an extreme blessing where the modems are shared amoung any number of applications. Auto-answer mode in particular can create a bad situation if the controlling process does nothing "overt" to reset the modem after a connection terminates. Some modems will not work reliably if not reset this way. An example is most 2400 baud modems, after being used at 1200 baud, will answer the next dial in call at 1200 baud if they are not reset. If the calling party is expecting 2400 baud, and the modems lock in at 1200, he's up the creek! I don't quite see your point when you remark that reinitialization is a "nuisance" and resending the command is "tedious". If the program is not sending the initialization sequence the modem needs it must be depending on the modem to be in a particular state. If thats the case, I hope you get some GOOD modems. Most modem handling programs generally start out their initialization sequence with ATZ (can we say reset?). Since programs rarely get annoyed ( annoying yes, annoyed no :-) ) and the programmer had to enter an explicit initialization string into the program to begin with ( unless he's a braver soul than this sysadmin ) the term nuisance hardly applies. As far as tedious is concern, even several separate commands and responses can hardly take more than a split second and programs get tired even less often than they get annoyed. The point is only marginally valid if the commands are being entered interactively but even in that case I have yet to find a modem I really trust after having DTR dropped. Michael H. Warfield (The Mad Wizard) | gatech.edu!galbp!wittsend!mhw (404) 270-2123 / 270-2098 | mhw@wittsend.LBP.HARRIS.COM An optimist believes we live in the best of all possible worlds. A pessimist is sure of it!
terry@wsccs.UUCP (Every system needs one) (10/22/88)
In article <2047@udccvax1.acs.udel.EDU>, tboutell@vax1.acs.udel.EDU (Thomas B Boutell) writes: > That's not quite true. Many Hayes- compatible modems will reset entirely > when DTR is toggled, but the correct response is merely to break the > connection and go into command mode. The reinitialization is a nuisance > which forces most programs to tediously resend any setup commands they > had already communicated to the modem after each call. Wrongo Tom. A Hayes modem can be set to reset on DTR drop. This is the correct usage on a UNIX system. The correct response, obviating a "tedious resend", is to do this. If a modem can't do this, it has no business calling itself "Hayes compatable"... it doesn't implement all features in the same way as Hayes does, so it is not. An interesting observation to make is which Hayes modem one is talking about... if the Hayes 1200 or 1200b is "the standard", then a Hayes 2400 is not Hayes compatable, as it does not implement ATF0. | Terry Lambert UUCP: ...{ decvax, ihnp4 } ...utah-cs!century!terry | | @ Century Software OR: ...utah-cs!uplherc!sp7040!obie!wsccs!terry | | SLC, Utah | | These opinions are not my companies, but if you find them | | useful, send a $20.00 donation to Brisbane Australia... | | 'I have an eight user poetic liscence' - me |