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keith_mc

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ATDT problem

I am using an old DOS dialer that I wrote to establish a connection and poll data from a point-of-sale system.  Everything works ok through the initialization (various AT commands) but when the ATDT[phone number] command is given, the modem responds with a list of stored phone numbers.  The dialer has worked fine with dozens of modems over the past 3 years.  I have just run into this problem with my LT Win Light modem running under Win95 and on another pc running Win95.
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magigraf

keith_mc...
These errors you get, are in DOS right??
Regards

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ASKER

I'm running in a DOS window under Win95.  

I think that you have a Winmodem.  These critters are only good with native windows applications.

Let's test this theory:

Try to run an old DOS-based communications software abd see if it works.  If not - you have a certified peice of junk for a modem.

Also, what company made the modem?  I couldn't find any info on "LT Win Light" modems, are you sure that's the name?
just run the Win95 dialer. It's much easier.

plus WinModems has the reputation to run only on Windows based tcp/ip programs.
Other DOS programs seem to behave ok (i.e. procomm).  The modem is a LT Win modem in an off-the-shelf HP Pavilion.

Using the Win95 dialer isn't an option because the dialer needs to be automatically launched by another application at a preset time.  The whole process (dialing and polling of the registers) has to be unattended.  I would be happy to use another dialer like procomm or Win95's dialer if it would work.  My application would have to launch the dialer, passing the phone number as a command line parameter.  The dialer would then have to leave the connection open while my program launches a DOS app to do the polling.  The dialer would also have to give up control of the com port so the DOS app can run.  Finally, there needs to be a reliable way to hang up the phone after the polling is complete.

Thanks
    Check the modem from Hyperterminal.  Send an AT command from there.  I don't know the modem, but if it responds 'differently' to normal AT commands, then you'll just have to alter your dialer a little.  If it responds normally, then maybe there's something you've overlooked in the dialer.  Usually, spewing phone numbers is a result of an ATI or dump of the S Registers...
BTW, it is possible to launch the Win95 dialer from another program (but that's a different question altogether).

Can we change the question?  I wouldn't mind using another dialer like the Win95 dialer.  I can launch that from my application easily enough.  The problem is passing the phone number since this will be an automated event.



   I wish I could see this modem...
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alexo
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Ooops, submitted it too quickly...

You can also CreateFile() your serial port ("COM1") and use the ReadFile(), WriteFile() and the various Comm functions.

Since the problem only seems to occur with my dialer and since I need to get away from that DOS routine anyway, I think I'll pursue your suggestion.  Thanks.