Re: Urgent, COM port problem

From: CE (hcheng_at_optonline.net)
Date: 02/27/04 

Date: Fri, 27 Feb 2004 18:01:32 -0500

Thanks so much!!!

When use createfile() function, it works,WriteFile() call does not return
error.my setting is:
 dcb.BaudRate = 9600;
 dcb.Parity = NOPARITY;
 dcb.ByteSize = 8;
 dcb.StopBits = ONESTOPBIT;
 dcb.fDtrControl = DTR_CONTROL_DISABLE;
 dcb.fOutxCtsFlow = TRUE;
 dcb.fRtsControl = RTS_CONTROL_ENABLE;

When I use same program with old small image, no problem.
For this new image, I can't see data from my Serial device. But I don't get
error return code from WriteFile() call.

"Paul G. Tobey [eMVP]" <ptobey_no_spam@instrument_no_spam.com> wrote in
message news:eaVR4MY$DHA.2804@tk2msftngp13.phx.gbl...
> Check the registry on the running device. Is the COM port driver listed
in
> HKLM/Drivers/Active? If not, check the settings in the registry for the
> driver (HKLM/Drivers/BuiltIn). If this is the case, you should probably
> capture the debug output from the OS and see if anything shows up.
>
> If the driver *is* listed, what happens when you try to send data to it?
> Does the data simply not appear, but CreateFile() works? Does the
> WriteFile() call return an error? If so, what error? Are you sure that
you
> don't have handshaking enabled and one of the handshake signals connected
to
> the wrong value (telling the port not to send)?
>
> Paul T.
>
> "CE" <hcheng@optonline.net> wrote in message
> news:OyFQpzX$DHA.792@TK2MSFTNGP11.phx.gbl...
> Blank
> I use PB4.2 built a CE 9MB image and I wrote a com port test program, I
can
> send data to COM port, no problem. Then I add some components to CE image,
> now CE image is about 20MB, now I found my program can't send data to
COM1.
> I have no idea why this happen, I searched components I added, they have
> nothing to do with COM port.
>
>
>
> Does any body know what caused this and how to fix this? Thank you very
> much!
>
>
>
>
>
>
>
>

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