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How to Clear RS232 Input buffer

Posted on 2006-07-13
Medium Priority
Last Modified: 2010-05-19
hi, All!

I try using PurgeComm(hComm, PURGE_RXCLEAR) to Clear RS232 Input Buffer before reading.
But It is not working, it always get the same message. Somebody could tell me how to do it.
And I also hope to clear input buffer automaticaly after I reading RS232.

Question by:abdate
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LVL 17

Expert Comment

ID: 17102489
You're using it correctly.
Make sure hComm is correct handle.

This is an example of clearing the rest of buffer after reading nCount bytes from it
    ReadFile(m_hPort, PChar(buf)^, nCount, nReceived, nil);
LVL 26

Accepted Solution

Russell Libby earned 150 total points
ID: 17103981

1 - Does the function return success?
2 - If its failing, what is the error code (message)


  if not(PurgeComm(hComm, PURGE_RXCLEAR)) then


Author Comment

ID: 17119294
Thanks all,

I find problem is from the other code. PurgeComm function is working well.


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