Modem Does not respond

[charudatta]

i have CreativeBlaster External Modem ( 56k). which is connected to HP900 L series, thru Mux Port. Getty process is started. but when i dials in modem does not respond. i tried US robotics 33.6 K modem still same. but when i use HP support link Modem i am able to dial in to the system...
is it that these modems are *too high tech*.
are there any specific modems i have to use for Unix box?

[A. Clay Stephenson]

Hi:

Not al all, almost any modem can be made to work. I suspect your problem is with cabling/DIP switch or NVRAM settings.

[Uday_S_Ankolekar]

Hi,

Any modem should respond if your mux ports are configured correctly for mode device.
In my environment I've mux with various types of modem for the L-class. It has been configured through sam and working perfactly fine for the fax software.
Try to create new modem port with sam. Also check the cables you are using to connect modem and mux port.

-USA..

[S.K. Chan]

From Technical DB ..

What does the HP 9000 expect from a modem?

The following list outlines the requirements for unsupported modems on HPUX. Refer to your modem documentation or call the modem manufacturer with this information and they should be able to provide you with the proper switch positions or commands to configure your modem.

* The modem should NOT ignore DTR.
* The modem should autoanswer when the HP computer raises DTR.
* The modem should hang up the line, disable autoanswer and return to command state when the computer drops DTR. This is AT&D2 on Hayes modem.
* We do not recommend that the modem does a power on reset when DTR is dropped as some modems temporarily raise CD during reset. In Hayes modems this would be AT&D3 - not recommended.
* The modem should assert carrier detect only when there is a carrier and should drop CD when the carrier is lost. This is AT&C1 on a Hayes modem.
* Hardware flow control (RTS/CTS) should be OFF.
* The modem should pass through BREAK.
* The modem speed should float, that is the modem should talk to a DTE at the same speed as the modem connects to other end. Turn OFF XON/XOFF flow control in the modem.

If there are no plans to use UUCP, the modem can be set to use fixed DTE speed and XON/XOFF flow control. If the HP port supports CTS/RTS, use fixed speed with no flow control to get communications working. When satisfied that a user can connect to the port repeatedly and from multiple modems, then turn on RTS on both the computer and the modem. Then if there are problems, they can be isolated to RTS/CTS.
* If modems connect but no data appears, turn off all compression, reliability, MNP, PEP, LAP or other advanced features and set the modem to be as dumb as possible. Get it working, then turn on advanced features.
* Do NOT use CCITT control signals on the modem or on the HP computer. This does not affect the ability of modem to use CCITT features such as V.22 and V.32.
* Remember to save the modem settings in non volatile memory on the modem so it retains the setup after power loss. This is AT&W on Hayes modems. Write down the settings somewhere so you will remember them if the modem loses its settings or they are changed.

[charudatta]

hi all thankx for your replies.
i re created moded thru SAM still does not work.. i guess cable is the problem.. i have modem which is connected to pc on parallel port. i am using that modem. how do i connect it to rs232 mux port..can i use printer cable to connect it ... i also has modem which has only serial connection. what accessories i have to buy for it to connect it to mux port

[charudatta]

hi all
small update
i connected my modem to mux using printer cable
i can dial out using kermit.
but modem still does not respond to dial in...
thankx in advance for your help

[Uday_S_Ankolekar]

Hi,

Here is the pin configuration for your modem cable.


-USA.

[Uday_S_Ankolekar]

Here in one more
http://us-support.external.hp.com/cki/bin/doc.pl/sid=aa908046121b17a0b8/screen=ckiDisplayDocument?docId=200000054370866

[John Dvorchak]

I used to run into a similar problem years ago. I found that "smart modems" respond to a call with "Ringing" or some similar response. The mux is set to echo all incomming message to the outgoing serial line. Well and good but what some "Smart Modems" do is hang up the phone when serial data is present on the serial port before a Carrier Detect (CD) is active and that is exactly what is happening if the mux is echoing. Now this isn't a mux problem, the problem is that the modem should have all responses disabled. In this way it will not send the "Ringing" and have it echoed back to the serial port signaling the modem to go back on hook. I don't remember the AT commands for echo off, no response etc. sorry.