Hello everybody,

I use 7 modems in my application to listen serial ports. I must be check modem status because sometimes my modem hang up in OH status mean that OH lamp is lighting and the telephone line will not be closed, if I close and open the problem everything will be ok but I must be solve modem hang up problem and I must be clear the buffer in every my process. I must be know modem status and If I check the modem hang up, I must be reset this modem. I use modem command like this in C# but I think it does not work sometimes,

AT&F\r + '13'

13 for enter.

Have a nice day.

7 Years
Discussion Span
Last Post by darkocean

It is a long time since I did anything with modems, but if I remember right, if the modem is connected you need to send "+++" to get it in to command mode before it will accept any "AT" commands. Otherwise the command is sent down the wire.

Edited by nick.crane: n/a


Yes I know +++ the escape character but I dont know when modem will be halt (endless hang up)


In fact, my problem is this : application work correctly in 3-5-10 hours and process about 100-150-200 processing (transaction) but 3-5-10 hours later or 150 processing later, application stoped its work but there is no error message, client is getting time out message and I dont know where is the problem :(

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