CMU 200 - serial communication

[vivek_sony]

I am trying to communicate between CMU200 and a PC card. For that I am originating a call from CMU 200(when synchronized) and replying back from the PC card. Currently, I am replying back by serial port by hyperterminal, using AT commands(ATA in this case).
Now, I am trying to automate this replying through LABview. the problem is that the serial read and write VIs are doing job of writting ATA to serial port but CMU 200 is not able to recognise. But on the other hand if I use hyperterminal CMU200 recognizes the serial communication easily.
The address are good, its not a issue.

[Dennis_Knutson]

Do you need to send a termination character? Hyperterminal does that for you. Try appending a CR or LF character (or both) the end of your write string. Be sure to use the actual control character and not the string "C" and "R". You can use the constants on the string palette or turn on '\' codes and enter \n or \r.

[vivek_sony]

Yeah, it works. Thanks.
I have one more problem. I am using CMU200 drivers to establish the call connection between the CMU and the mobile. For that I first synchronize the call between CMU and mobile and then make a mobile terminating call. The mobile replies back by serial port (using a LABview seial VI here).
Now, after replying by serial port, when LAABview VI tries to read the status of CMU, CMU looses connection and goes back to synchronous mode.
It may be beacuse of serial communication in between. I am not sure. Any inputs/solution from someone?

[LoganS]

I'm not familiar with the CMU 200, but perhaps a SPY capture would help me see what is going on. If you've never used NI-SPY, check out the following tutorial:

NI-SPY Tutorial

When complete, please post the .spy file as an attachment.

Logan S.