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johan
GpsGate
Posts: 14542
Joined: Wed Aug 04, 2004 10:40 pm
Location: Sweden
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I don't get an answer to my AT commands

Thu Jan 27, 2005 3:04 pm

I don't get an answer when sending AT commands to a modem

Problem
You send an AT command to a modem. The modem echoes the characters back you send, but the modem does not execute the AT command.

Cause
You have forgotten to add a carriage return + linefeed (CR/LF) to the end of the line.

Solution
Add CR/LF

C#
<font face="Courier New">objPort.Write(at_cmd + "\r\n");</font id="Courier New">

VB.NET
<font face="Courier New">objPort.Write(at_cmd + vbCrLf)</font id="Courier New">

VB 6.0 ActiveX
<font face="Courier New">objPort.Write at_cmd + vbCrLf</font id="Courier New">

where at_cmd is set to the AT command you want to send.



Regards,
Johan

Franson Support

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