How to keep alive RS232 connection

Hello everyone. I have a problem with RS232 communication. To activate the connection I have to send the string "RS232", then to keep it alive I have to send every second CR, but in the meantime, I must be able to send other character strings without delay on the same port (COM7). Can anyone help me?
Thanks
Solved!
Go to Solution.

RS232 standard does not require by itself to be kept alive someway, so I suppose is your remote device that requires it.
In every case, you could create a 1-sec timer and have its callback send CR periodically over the serial port.
To avoid conflicts between this task and the rest of the application you could use a lock: basically, after creating the lock, each function that wants to access the serial port must call CmtGetLock (), operate on the port and call CmtReleaseLock () afterwards. If the lock is owned by another function, other functions trying to get access are frozen waiting for the lock, so you must be careful in designing com-related function so that they are fast. If you do not want to have some function be blocked while waiting for the lock you can use CmtTryToGetLock instead of CmtGetLock. A few informations on locks can be found in this tutorial as well as in this chapter of the Programmer reference.
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<Cacho Nakamura> wrote in message news:[email protected]...
Dear all,
I intend to automatically detect network failures from my workstation client
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Browsing the documentation for related information I saw the keep-alive
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My doubts regarding this are the following:
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are periods where my WSC doesn't require to communicate with the server.
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error after all.
3) Once all ATMI functions start failing due to keep-alive detecting a
network failure, can the system recover on its own? or must I reconnect to
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Regards.

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same to u .
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[email protected]
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Trace (replaced sensitive information):
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Thu Apr 29 15:05:50 2010 <958012725463463784> URL::parseHeaders: StatusLine set to [200 OK]
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