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monkeyboy12
Tl Posts:
6

Posted - 10/22/2001 5:27:13 PM  Show Profile  Email Poster  Edit Message
I've got hold of a 3com USR 56k Message Modem, the product code of which is 71-245668-01. First thing I noticed on trying it out was that it connected at 50.6k, which I thought sounded pretty good: with a previous modem I'd got 49.3k max and 48k most of the time, and occasionally 33.6k. However, the performance wasn't quite what I expected so I thought I'd try to limit the connect speed. The problem is, no matter what values of &U and &N I use, the modem ALWAYS connects at 50.6k. I can't seem to affect the connection speed at all. Has anyone else encountered this problem or discovered a way around it?
v.Richard
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USA		Posted - 10/22/2001 6:49:58 PM  Show Profile  Email Poster  Edit Message  v.Richards Homepage
I would suggest use of Hyperterminal to test/check firmware version/ commands -
www.modemsite.com/56k/x2-hyperterm.htm

at i7
shows firmware version;

at&$
will display the &u&n parameters

at&F1&u#&n#
then dial

Note, some USR firmware requires both &U&N values otherwise the limit command doesn't work.

Aloha,
Richard

monkeyboy12
Tl Posts:
6

Posted - 10/22/2001 8:29:20 PM  Show Profile  Email Poster  Edit Message
Thanks for the reply, but I'm afraid it doesn't solve my problem. Here is the output from ati7 in case it's any help.

Product type CTR-21 External
Product ID: 24566801
Options V32bis,V.80,V.34+,x2,V.90
Fax Options Class 1/Class 2.0
Line Options Caller ID
Voice Options Speakerphone, TAD
Clock Freq 92.0Mhz
EPROM 256k
RAM 32k

FLASH date 2/26/99
FLASH rev 14.9.1

DSP date 2/26/99
DSP rev 14.9.1

When I did an at&$, it showed numbers for &N and &U right up to 57,333 on both sides. When I use an init string with both &U and &N defined, I still only ever connect at 50.6k. I've also tried doing it via Hypertrm using the basic string you suggested, but I still always only get 50.6k. I've tried doing it with only &N defined. Still 50.6k. I've tried doing it with various numbers for both. Still 50.6k. Simply seems to be broken.

Bob Starnes
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4360

USA		Posted - 10/22/2001 9:09:46 PM  Show Profile  Email Poster  Edit Message
Post a modem log.
monkeyboy12
Tl Posts:
6

Posted - 10/23/2001 7:59:47 AM  Show Profile  Email Poster  Edit Message
Here goes...

10-23-2001 15:43:59.35 - U.S. Robotics 56K Message in use.
10-23-2001 15:43:59.35 - Modem type: U.S. Robotics 56K Message
10-23-2001 15:43:59.35 - Modem inf path: USRR&D~1.INF
10-23-2001 15:43:59.35 - Modem inf section: Modem1
10-23-2001 15:43:59.61 - 115200,N,8,1
10-23-2001 15:43:59.61 - 115200,N,8,1
10-23-2001 15:43:59.61 - Initializing modem.
10-23-2001 15:43:59.61 - Send: AT<cr>
10-23-2001 15:43:59.61 - Recv: AT<cr>
10-23-2001 15:43:59.73 - Recv: <cr><lf>OK<cr><lf>
10-23-2001 15:43:59.73 - Interpreted response: Ok
10-23-2001 15:43:59.73 - Send: AT&F&B1&A3E0Q0V1&C1&D2&P1S0=0<cr>
10-23-2001 15:43:59.74 - Recv: AT&F&B1&A3E0Q0V1&C1&D2&P1S0=0<cr>
10-23-2001 15:43:59.87 - Recv: <cr><lf>OK<cr><lf>
10-23-2001 15:43:59.87 - Interpreted response: Ok
10-23-2001 15:43:59.87 - Send: ATS7=60S19=0L0M0&M4&K1&H1&R2&I0B0X4<cr>
10-23-2001 15:44:00.00 - Recv: <cr><lf>OK<cr><lf>
10-23-2001 15:44:00.00 - Interpreted response: Ok
10-23-2001 15:44:00.00 - Send: AT&F1&U28&N33<cr>
10-23-2001 15:44:00.13 - Recv: <cr><lf>OK<cr><lf>
10-23-2001 15:44:00.13 - Interpreted response: Ok
10-23-2001 15:44:00.13 - Dialing.
10-23-2001 15:44:00.13 - Send: ATDT;<cr>
10-23-2001 15:44:00.13 - Recv: ATDT;<cr>
10-23-2001 15:44:01.58 - Recv: <cr><lf>OK<cr><lf>
10-23-2001 15:44:01.58 - Interpreted response: Ok
10-23-2001 15:44:01.59 - Dialing.
10-23-2001 15:44:01.59 - Send: ATDT###########<cr>
10-23-2001 15:44:01.59 - Recv: ATDT08089977001<cr>
10-23-2001 15:44:21.45 - Recv: <cr><lf>CONNECT 50666/ARQ/V90/LAPM/V42BIS<cr><lf>
10-23-2001 15:44:21.45 - Interpreted response: Connect
10-23-2001 15:44:21.45 - Connection established at 50666bps.
10-23-2001 15:44:21.45 - Error-control on.
10-23-2001 15:44:21.45 - Data compression on.

&N33 should give it a ceiling connect speed of 49333bps, but...

monkeyboy12
Tl Posts:
6

Posted - 10/25/2001 5:07:55 PM  Show Profile  Email Poster  Edit Message
Right, further to this problem I've now got another. I've downloaded the Control Center, which only actually recognised my modem after I downloaded the update, which, of course, was in no way linked from USR-emea's site. Now it recognises my modem, and says there is a firmware update available. Trouble is, when I click on Instant Update, the program simply displays the Product Information page and greys out the other buttons. The first time after installation it had displayed the relevant pages, but the modem had disappeared from the list of updateable items when I went to press Update Now. I've also tried using the Control Center to limit the modem speed, but even that doesn't work. Can anyone work this all out?
Bob Starnes
Tl Posts:
4360

USA		Posted - 10/25/2001 8:10:56 PM  Show Profile  Email Poster  Edit Message
Don't know about the Control Center, perhaps someone can advise you about it.

For limiting connect speed, if your ISP is X2/V.90, have you tried disabling V.90 and letting the modem connect with X2 and checking to see if the &Un and &Nn will limit the speeds in X2?

monkeyboy12
Tl Posts:
6

Posted - 10/26/2001 5:51:30 PM  Show Profile  Email Poster  Edit Message
Curiouser and curiouser... My ISP doesn't support X2, so instead I disabled v.90 and let it connect under v.34. Under v.34, the &U &N combo seems to work fine:

<uninteresting bits snipped>
10-27-2001 00:47:10.73 - Initializing modem.
10-27-2001 00:47:10.73 - Send: AT<cr>
10-27-2001 00:47:10.73 - Recv: AT<cr>
10-27-2001 00:47:10.86 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:47:10.86 - Interpreted response: Ok
10-27-2001 00:47:10.86 - Send: AT&F&B1&A3E0Q0V1&C1&D2&P1S0=0<cr>
10-27-2001 00:47:10.86 - Recv: AT&F&B1&A3E0Q0V1&C1&D2&P1S0=0<cr>
10-27-2001 00:47:10.99 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:47:10.99 - Interpreted response: Ok
10-27-2001 00:47:10.99 - Send: ATS7=60S19=0L0M0&M4&K1&H1&R2&I0B0X4<cr>
10-27-2001 00:47:11.12 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:47:11.12 - Interpreted response: Ok
10-27-2001 00:47:11.12 - Send: ATS32.6=1&U5&N12<cr>
10-27-2001 00:47:11.25 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:47:11.25 - Interpreted response: Ok
10-27-2001 00:47:11.25 - Dialing.
10-27-2001 00:47:11.25 - Send: ATDT;<cr>
10-27-2001 00:47:12.70 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:47:12.70 - Interpreted response: Ok
10-27-2001 00:47:12.71 - Dialing.
10-27-2001 00:47:12.71 - Send: ATDT###########<cr>
10-27-2001 00:47:26.52 - Recv: <cr><lf>CONNECT 24000/ARQ/V34/LAPM/V42BIS<cr><lf>
10-27-2001 00:47:26.52 - Interpreted response: Connect
10-27-2001 00:47:26.52 - Connection established at 24000bps.
~~~~~~~~~~~~~~~~~~
Then I renabled v.90 but left in the same &U &N combo. It still connected using v.34:

10-27-2001 00:51:19.01 - Initializing modem.
10-27-2001 00:51:19.01 - Send: AT<cr>
10-27-2001 00:51:19.01 - Recv: AT<cr>
10-27-2001 00:51:19.14 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:51:19.14 - Interpreted response: Ok
10-27-2001 00:51:19.14 - Send: AT&F&B1&A3E0Q0V1&C1&D2&P1S0=0<cr>
10-27-2001 00:51:19.14 - Recv: AT&F&B1&A3E0Q0V1&C1&D2&P1S0=0<cr>
10-27-2001 00:51:19.27 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:51:19.27 - Interpreted response: Ok
10-27-2001 00:51:19.27 - Send: ATS7=60S19=0L0M0&M4&K1&H1&R2&I0B0X4<cr>
10-27-2001 00:51:19.40 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:51:19.40 - Interpreted response: Ok
10-27-2001 00:51:19.40 - Send: ATS32.6=0&U5&N12<cr>
10-27-2001 00:51:19.53 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:51:19.53 - Interpreted response: Ok
10-27-2001 00:51:19.53 - Dialing.
10-27-2001 00:51:19.53 - Send: ATDT;<cr>
10-27-2001 00:51:20.95 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:51:20.95 - Interpreted response: Ok
10-27-2001 00:51:20.95 - Dialing.
10-27-2001 00:51:20.95 - Send: ATDT###########<cr>
10-27-2001 00:51:34.98 - Recv: <cr><lf>CONNECT 24000/ARQ/V34/LAPM/V42BIS<cr><lf>
10-27-2001 00:51:34.98 - Interpreted response: Connect
10-27-2001 00:51:34.98 - Connection established at 24000bps.
~~~~~~~~~~~~~~~~~~~~~~~~
I then increased &N by 1 over a series of connections. It still connects using v.34 until you get to &N17, at which point it reverts to connecting using v90 and 50666bps:

10-27-2001 00:54:49.49 - Initializing modem.
10-27-2001 00:54:49.49 - Send: AT<cr>
10-27-2001 00:54:49.49 - Recv: AT<cr>
10-27-2001 00:54:49.61 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:54:49.61 - Interpreted response: Ok
10-27-2001 00:54:49.61 - Send: AT&F&B1&A3E0Q0V1&C1&D2&P1S0=0<cr>
10-27-2001 00:54:49.62 - Recv: AT&F&B1&A3E0Q0V1&C1&D2&P1S0=0<cr>
10-27-2001 00:54:49.74 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:54:49.74 - Interpreted response: Ok
10-27-2001 00:54:49.74 - Send: ATS7=60S19=0L0M0&M4&K1&H1&R2&I0B0X4<cr>
10-27-2001 00:54:49.88 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:54:49.88 - Interpreted response: Ok
10-27-2001 00:54:49.88 - Send: ATS32.6=0&U5&N17<cr>
10-27-2001 00:54:50.00 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:54:50.00 - Interpreted response: Ok
10-27-2001 00:54:50.00 - Dialing.
10-27-2001 00:54:50.00 - Send: ATDT;<cr>
10-27-2001 00:54:51.44 - Recv: <cr><lf>OK<cr><lf>
10-27-2001 00:54:51.44 - Interpreted response: Ok
10-27-2001 00:54:51.44 - Dialing.
10-27-2001 00:54:51.44 - Send: ATDT###########<cr>
10-27-2001 00:55:11.37 - Recv: <cr><lf>CONNECT 50666/ARQ/V90/LAPM/V42BIS<cr><lf>
10-27-2001 00:55:11.37 - Interpreted response: Connect
10-27-2001 00:55:11.37 - Connection established at 50666bps.

Post call diagnostics (ati6) revealed that although it claimed a connect speed of 50666 it dropped down to 28800, the value specified by &N. I increased &N to 18 and the speed then dropped to 29333. However, I then increased it to 20 and no speed drop has been observed since.

Curiously, when I dropped &N back down again to 15, which previously yielded a v34 connection, the modem continued to connect using v90 and at 50.6k. And no speed drops were evident in postcall diagnostics.

The only conclusion I can reach is that the firmware for this modem is utterly flawed, and my only hope is to pester USR for help.

Bob Starnes
Tl Posts:
4360

USA		Posted - 10/27/2001 12:01:35 AM  Show Profile  Email Poster  Edit Message
If you know of an ISP that's local to you that supports X2 then you might try dialing into it (just don't attempt to log on) using Hyperterminal to test the &Un and &Nn settings.

See http://modemsite.com/56k/x2-hyperterm.htm for setting up Hyperterminal.

And http://modemsite.com/56k/usehyper.htm for using Hyperterminal to connect to other ISPs.

I do recall one other (OEM) USR modem that didn't respond properly to the &Un and &Nn settings, don't recall the model number though.

monkeyboy12
Tl Posts:
6

Posted - 10/28/2001 12:01:52 PM  Show Profile  Email Poster  Edit Message
It doesn't seem to want to play: if I dial up to an ISPs X2 only number, it still says it connects using v90. If I disable v90, it refuses to connect at all to the X2 only number, and connects at v34 to the standard v90/X2 numbers.

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