Re: Custom app & Winlogon.exe fighting

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On 6 Nov 2006 14:53:21 -0800, ckramer7070@xxxxxxxxx wrote:


Really odd functioning from the MSComm, we can open and set properties
for the port and run data through it correctly but when it comes time
to close the program and kill the port the computer will slow down
dramatically. Funny thing is if we initialize the same comm again the
lag goes away. Tried various things with the thresholds and buffer
clearing, not yet resolved. We are moving data RS232 to a converter
then RS485 to 2 temp-controllers, have any suggestions on MSComm
properties setup?


Finally got this resolved by setting the MSComm.RThreshold = 0 while
running a do loop to check the incomming data and exit when it has
received the full signal. I guess setting the RThreshold to 0 allows
the MSComm to be skipped and doesn't slow down the signal as much.

MSComm.RThreshold = 0

<quote>
Setting the RThreshold property to 0 (the default) disables generating
the OnComm event when characters are received.
</quote>

Since you are reading the characters yourself, you are not relying on
the OnComm event to receive the characters.

This is Ok if you are doing a 'question and answer' type thing, but
would be a problem if your App was meant to always 'listen'.

It sounds like your App was getting hammered with OnComm events when
you were trying to shut it down.

Glad you've found a solution.
.

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