Re: [OT?] Reading hardware from thread

From:
"Yi Ren" <yren@lasercraftinc.com>
Newsgroups:
microsoft.public.vc.mfc
Date:
Wed, 18 Apr 2007 14:26:07 -0400
Message-ID:
<uOwYqbegHHA.392@TK2MSFTNGP06.phx.gbl>
My suggestion is to use a seperate thread to perform the I/O reading. Inside
the thread:

hTimer = CreateWaitableTimer(..);
SetWaitableTimer(hTimer, ...);

do
{
    ReadIo(...);
    Do something with the reading result (for example, send a usre defined
message to your maim thread for the reading) ....

    SetWaitableTimer(hTimer, ...);
    WaitForSingleObject(hTimer, ...);

} while (exit_condition);

This way, your main app. can go on to do its own thing utill it receives the
result from the I/O reading; or if it has nothing to do, just wait on the
I/O reading thread using WaitForSingleObject.

Eric

"Anders Eriksson" <andis59@gmail.com> wrote in message
news:y5ot62o2p1f5.dlg@ostling.com...

Hello,

This might be a slightly Off Topic question but I don't know where else to
put it.

I have a digital I/O PCI Card that I have to read at least once every 35
ms
(We are using the I/O card for communicating with an PLC that has about 35
ms cycle time.

I have tried using OnTimer() but it will not work with these small times.
So I was thinking that I maybe could start a thread that reads the I/O
card
continuously in a loop and creates Events Messages when something changes.

Since I haven't done anything like this before I just want to check with
you guys and girls if it's a stupid idea or not!?

Any suggestion on how to solve the problem would be appreciated!

// Anders
--
English is not my first, or second, language
so anything strange, or insulting, is due to
the translation.
Please correct me so I may improve my English!

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