bei@dogface (Bob Izenberg) (04/17/91)
I'm going to be in the market for a modem for a 3B2/400 in the near
future. Telebit is a likely choice, but I'd like some other options.
When I last looked, Hayes support for 3B2s wasn't the best. The modem
that I go with should do at least 2400 baud, and should be able to have
DCD true all the time, dipping DCD and then raising it when a valid carrier
is detected. Transparency to uucp 'g' is a must.
Any comments about pricing, support, reliability or anything else are
welcome.
Thanks!
-- Bob
Bob Izenberg
cs.utexas.edu!dogface!bei [ ] "So young, so bad... So what!"
512 346 7019 Wendy O. Williamsjiro@shaman.com (Jiro Nakamura) (04/18/91)
In article <a50i11w164w@dogface> bei@dogface (Bob Izenberg) writes: >I'm going to be in the market for a modem for a 3B2/400 in the near >future. Telebit is a likely choice, but I'd like some other options. >When I last looked, Hayes support for 3B2s wasn't the best. The modem >that I go with should do at least 2400 baud, and should be able to have >DCD true all the time, dipping DCD and then raising it when a valid carrier >is detected. Transparency to uucp 'g' is a must. Aren't Telebits the only ones that do UUCP-g spoofing? Does anyone else do this? Also, Telebit can only do spoofing in PEP mode, right - so that rules out compatibility with other modems.... I personally own a T2500 and am very happy with it. I think the funky DCD handling you require is under register 131=3, I'm not sure so here's the whole gamuk: S131 = 0 DCD always on 1 DCD on when carrier detected 2 DCD on when modem ready to accept commands or data 3 DCD on when modem ready to accept command or data. When carrier is lost, DCD is turned back off for the amound of time specified by the S47 register and then back on. 4 DCD is the inverse of CTS in command and online modes. Hope this helps. Telebit Tech support (1800-Telebit) is usually excellent by computer standards. - jiro -- Jiro Nakamura jiro@shaman.com Shaman Consulting (607) 253-0687 VOICE "Bring your dead, dying shamans here!" (607) 253-7809 FAX/Modem
bob@MorningStar.Com (Bob Sutterfield) (04/18/91)
In article <1991Apr18.005851.869@shaman.com> jiro@shaman.com (Jiro Nakamura) writes:
Aren't Telebits the only ones that do UUCP-g spoofing? Does anyone
else do this?
I don't know of anyone else. To interoperate with Telebits, they'd
need to adopt (i.e. license) Telebit's spoofing scheme.
Also, Telebit can only do spoofing in PEP mode, right - so that
rules out compatibility with other modems....
The T2500 (firmware rev 7 or better) and T1600 can spoof over V.32
connections if either MNP or V.42 error correction is operating.bill@wrangler.WLK.COM (Bill Kennedy) (04/19/91)
bob@MorningStar.Com (Bob Sutterfield) writes: Following up what jiro@shaman.com (Jiro Nakamura) writes: [who's following up Bob Izenbergs 3B2 modem question, deleting most of it... ] Jiro>> Also, Telebit can only do spoofing in PEP mode, right - so that Jiro>> rules out compatibility with other modems.... Bob>The T2500 (firmware rev 7 or better) and T1600 can spoof over V.32 Bob>connections if either MNP or V.42 error correction is operating. Just a particle of input here since I have tried the V.32 uucp spoofing with a T-1600 into a T-2500. As Bob points out it works and is reliable. The downside is that 800-900cps is the best transfer rate I have seen while the same T-2500 to a TB+ gets 1400-1500cps on the same two machines using PEP. I like the T-1600 just fine but the Trailblazers still haul the uucp freight here. Pursuant to Bob I's original question here's my $0.02 for others with similar curiosity. Wrangler is an NCR Tower 32/400 but its serial card has some idiosyncracies similar to a 3B2 (there's one of them here too). All of the Telebits have the capability to keep DCD high and dip it for some period of time after losing "real" carrier, that's how mine are set up here. Here's what I would do in several different scenarios: Lotsa money, mostly uucp, but full duplex (e.g. vi from/to remote) required and maybe SL/IP or PPP - get a T-2500 and do your uucp work PEP and the full duplex stuff V.32 Some money, almost 100% uucp - get a T-2000 (Trailblazer Plus) and stick with PEP, live with the micropacket jerkiness or use 2400bps for full duplex Money tight but gotta go fast, mostly uucp - get a T-1000 and ignore that it will not do compression on the fly (which isn't much of a win anyway) or better than 9600bps on the analog side of the line, same caveat for full duplex. The T-1000 is just fine for local PEP calling and light duty long distance, the speed difference for a T-2000 in my case (99.9% LD) pays for the $$ difference in a hurry Money tight, light uucp, heavy full duplex or SL/IP - get a T-1600. It's the cheapest one in the line, it won't do PEP. As long as you have a V.32 uucp neighbor you're OK, transfer rates are decent, and in my limited experiments the V.32 performance is OK. Over a SL/IP link I've seen repeatable ftp transfer rates of 1600cps, 800-900cps best case uucp, worse if you don't enable spoofing. I have five Telebits, two external T-2000s (in use 'round the clock) and a T-1600 (ditto) on wrangler, an internal TB+ in the luggable road warrior, and a T-1000 that "floats" from machine to machine for temporary PEP use. If I could only have one modem it would be a T-2500. If I could have only two it would be a T-2000 and a T-1600 (in a very close tie with the internal TB+ for the luggable). If I had all or mostly local uucp connections and was near-broke I'd have a T-1000 but if I did any BBS type stuff I'd look at a US Robotics Dual Standard (I don't know if it can do DCD stuff like Telebits can). Sorry for the bulk, but the question comes up from time to time and the water gets muddier as new and different models are introduced. BTW another nice thing about Telebit is better than average tech support, free firmware fixes for bugs, and reasonable (IMHO) charges for firmware upgrades. I hear that the myriad of firmware rev levels on the T-2500 is something of a headache but I don't have one so I don't really know. -- Bill Kennedy uucp {att,cs.utexas.edu,pyramid!daver}!ssbn.wlk.com!bill internet bill@ssbn.WLK.COM or ssbn!bill@attmail.COM
bud@rescon.UUCP (Alex Batyi) (04/20/91)
In article <BOB.91Apr18082452@volitans.MorningStar.Com> bob@MorningStar.Com (Bob Sutterfield) writes: >In article <1991Apr18.005851.869@shaman.com> jiro@shaman.com (Jiro Nakamura) writes: > Aren't Telebits the only ones that do UUCP-g spoofing? Does anyone > else do this? > >I don't know of anyone else. To interoperate with Telebits, they'd >need to adopt (i.e. license) Telebit's spoofing scheme. My MultiTech224EH spoofs UUCP. Also I thought algorythms couldn't be copyrighted. -- AJB +1 215 788 5957 {cdin-1 wells}!alba2l!bud Quote:"If you lose your memory, forget it!" bud@alba2l.UUCP Agnostic, dyslexic, insomniac: Someone who stays up all night wondering if there really is a Dog.
woods@robohack.UUCP (Greg A. Woods) (04/22/91)
In article <a50i11w164w@dogface> bei@dogface (Bob Izenberg) writes: > I'm going to be in the market for a modem for a 3B2/400 in the near > future. Telebit is a likely choice, but I'd like some other options. > When I last looked, Hayes support for 3B2s wasn't the best. The modem > that I go with should do at least 2400 baud, and should be able to have > DCD true all the time, dipping DCD and then raising it when a valid carrier > is detected. Transparency to uucp 'g' is a must. Hmmm... First off, unless you have an older, broken, version of HDB-UUCP, then you *don't* need to have DCD high. On the other hand, if you do have an older, broken, version of HDB-UUCP, you need a relatively smart modem that can hold DTR up normally, but drop it for a few seconds when carrier is lost (i.e. when it hangs up). Some other folks who followed up have suggested Telebit modems with their PEP support and UUCP 'g' protocol spoofing. I don't think that's what you meant -- I'd guess you only want to run UUCP 'g' through your modem, and you would like at least 2400 bps throughput. I'm currently running two Hayes modems on this 3B2/400. I certainly don't have them set to assert DCD continuously either. They work fine for the most part, *BUT* they occasionally hang the port. I'm not sure whose "fault" this is, but I suspect the modems are part of it, since I've used other modems with no problem. Periodically, usually after conversing with a Telebit modem of some sort, and after going on-hook, the RD and SD, or sometimes just the SD light will go on solid. However, there seems to be no actual traffic through the port. At the same time connecting to the port with cu results in nothing. Temporary disconnection of the RS-232 cable does nothing to help. Disconnecting the RS-232 and re-setting the modem also does nothing. Attempting to drop DTR via 'stty 0' does nothing. The only thing that seems to restore normal operation (short of re-booting) is to re-set the modem while the RS-232 is still connected. For the record, I have a Hayes SmartModem 2400 and a Hayes V-Series SmartModem 9600 currently attached to an EPORTS card. > Any comments about pricing, support, reliability or anything else are > welcome. The very best 2400 baud modem I ever used anywhere, including on the 3B2 was an AT&T DataPhone II 2224B. It had the smarts to be able to run with DTR as I describe above, and seemed to *always* work with exceptional reliability -- until it took a lightning bolt in the phone jack.... :-( -- Greg A. Woods woods@{robohack,gate,eci386,tmsoft,ontmoh}.UUCP +1 416 443-1734 [h] +1 416 595-5425 [w] VE3-TCP Toronto, Ontario; CANADA
tech@mich-ns.UUCP (Mich. Network Sys. TECH SUPPORT) (04/25/91)
In article <1991Apr18.005851.869@shaman.com> jiro@shaman.com (Jiro Nakamura) writes: "In article <a50i11w164w@dogface> bei@dogface (Bob Izenberg) writes: ">I'm going to be in the market for a modem for a 3B2/400 in the near ">future. Telebit is a likely choice, but I'd like some other options. ">When I last looked, Hayes support for 3B2s wasn't the best. The modem ">that I go with should do at least 2400 baud, and should be able to have ">DCD true all the time, dipping DCD and then raising it when a valid carrier ">is detected. Transparency to uucp 'g' is a must. " " Aren't Telebits the only ones that do UUCP-g spoofing? Does anyone "else do this? Also, Telebit can only do spoofing in PEP mode, right - so that "rules out compatibility with other modems.... Not sure if anyone else does it. The T2500 does protocol spoofing for UUCP-G, KERMIT, XMODEM and YMODEM in PEP mode. The T1600 (Telebit's V.32 modem) does spoofing in V.32 mode. " Hope this helps. Telebit Tech support (1800-Telebit) is usually "excellent by computer standards. " Your local Telebit distributor should be able to lend assistance too. -- Michigan Network Systems Technical Support Division 1-800-736-5984 BBS: +1 313 343 0800 TELEBIT DIGIBOARD WESTERN DIGITAL 3COM SCO INTERACTIVE UNIX MICROPOLIS ADAPTEC