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Frank Krauss
Tl Posts:

Posted - 12/13/2006 5:35:24 AM  Show Profile  Email Poster  Edit Message
Hello everyone,

I have a Diamond SupraExpress 56e Pro Modem.
ATI3 output is "SupraExpress 56e Pro V.92"
ATI7 output is "RCV56DPF-PLL L8571A Rev 30.03/04.00"
Therefore this is using the "Conexant ACF 56k" Chipset.

This Modem is being used on a Pentium 4 P.C. running the
Linux Operating System at Kernel 2.6.9.
The Software controlling the Modem is PPP at level 2.4.4.

The Modem is being used to support a 24/7 connection to my ISP.

When my ISP periodicly re-cycles the Line and drops the connection, all of the Lights go off except, naturally the PWR (Power) light and the TR (DTR) Light.
For some reason the DTR Light is staying ON.
Due to this, the PPP Program does NOT reconize that the connection has dropped and therefore it does not restart the connection, as it should.

When this occurs, I have to physically turn OFF and ON the Modem in order to get PPP to reconize the dis-connect.

This is not the way my other Modems worked.
Normally when a Line dropped the DTR would get turned OFF.

I have attempted to place in the setup various AT commands
such as "AT&F0", "AT&D2" and "ATS13=1", which I got from various places on the Web, but non of these options caused the DTR light to drop.

I would appreciate very much if someone could tell me the option that I have to enter to get the DTR signal to drop when the connection is broken.

Thanking everyone in advance for any information on solving this problem.

Frank Krauss

Tl Posts:

Posted - 12/13/2006 8:35:37 AM  Show Profile  Email Poster  Edit Message  v.Richards Homepage
DTR = Data Terminal Ready.
In this instance, the computer/computer COM port is the data terminal. The modem is the data set. The computer controls the DTR signal. The computer/COM port stays in a ready state, so the DTR signal correctly stays high.

Would seem to me that the PPP program shouldn't use the DTR signal to detect loss of conection; but, if that's your only option, you'd need to use a breakout box or build a custom cable to force DTR low by, for example, to CD.

Aloha! Richard.

Frank Krauss
Tl Posts:

Posted - 12/13/2006 11:55:01 AM  Show Profile  Email Poster  Edit Message
Hello Richard,

Thank you for responding to my problem so fast.
I'm sorry I wasn't clearer on what my problem is.

The line and the Software controlling it, PPP, are working
I have had no problems like this when using other Modems,
like an Elsa or a US Robotics.
When the Connection was dropped by the ISP, the DTR was
made Low, the light went out and that informed the
Software, PPP, to re-dial the connection.

This Modem is not working like the other ones did.
Something in it is preventing the DTR line from going Low.

I believe its some type of command to force this modem
to behave like the others did but I don't know what it is.

Thank you for your attempt to help anyway.


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