🚀 go-pugleaf

"Neil P." <nporve01@hotmail.com> wrote in message
news:42820cad$1@newsgroups.borland.com...

> I don't use CheckCommStatus() anywhere in my snippet?

I meant ClearCommError(), sorry.

> I tested the respond time of the embeded unit using Hyperterminal
> and it never fails ( < 1ms) you can't even time it, if all your using is
> Hyperterminal, just see that it always respond immediately.

Then that suggests your code really is not set up properly, if it is taking
up to 10 seconds to get that response.  I am still of the opinion that you
need to get rid of ClearCommError() altogether, for the purpose of polling
thequeue status anyway.  If the code still runs slowly after removing it,
then something else is still messed up in your remaining code.  My guess
would be that either 1) you did not actually configure the baud rate
correctly in your code, or 2) you did not set up the timeouts properly when
you opened the serial port.  But I cannot say for sure, because you never
showed any of that code yet.

> I don't understand why? Everything tells me the byte should be there
> and maybe it is, but definetly I am doing something terribly wrong in
> my Read snippet, because I am not getting that byte????

You are not using overlaped I/O properly to begin with, because you are
relying on your queue status and not the overlapped status.  For that
matter, since your code is processing in a serialized manner anyway, your
Read() method can't return until the reading actually finsihes, so why are
you using overlapped I/O at all?  It is not gaining you anythig in this
situation, so you could just remove it altogether and let ReadFile() operate
synchronously instead.


Gambit