Remote COM Port - Can send commands to modem but not receiving results

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taa, 10.5.2007, 05:44, 71.59.209.61
Can send commands to modem but not receiving results

Hi, I have a US Robotics V.92 *hardware* modem (not winmodem) and I'm able to do a telnet to Piracom and issue AT commands. The modem echos back the characters I type for the commands, but nothing comes back for the command results. I *do* have verbose results turned on, and I'm able to issue AT commands using Hyperterminal with no problem. The modem is brand new and has the latest firmware. What am I doing wrong?
Jan, 10.5.2007, 18:39
Re: Can send commands to modem but not receiving results

I haven't tested the application with modem yet. I think that the reason is in flow control. Actually the piracom doesn't support flow control but it may be required by your modem. You should try to connect pins DTR+DSR and RTS+CTS on the modem connector to make two backloops for these signals. If this will work, it can be easily implemented in the piracom.
taa, 11.5.2007, 02:41, 71.59.209.61
Re: Can send commands to modem but not receiving results

I forgot to mention this is an internal modem so I have no way to to create the backloops you describe. But if the problem was flow control, how would the modem be able to echo the characters as I type them?
Jan, 11.5.2007, 18:55
Re: Can send commands to modem but not receiving results

I can imagine the situation. Please try http://pira.cz/eng/piracom12.zip - it includes DTR and CTS control so the modem should be satisfied. Please let me know.

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