Re: What's SerialPort can not fire DataReceived event.

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Dear Dick,
Thank you for your infomation. but my platform has serial
driver code and using API to operation it is fine.
and Using WM5 OS is OK. and when my device is clean boot still cannot
generation a "DataReceived" event.
I guess the event implement method is to create a thread to monitor RX
buffer and to compare "ReceivedByteThreshold" condition. When I to use
ReadExisting() can get Rx date, so I cannot accept the problem due to
serial driver has bugs.


BTW if your device just after suspend/resume has the issues. I guess
serial drivers reconfiguration UART GPIO when Power_Down but Power_Up
not to correct restore original setting.

BTW again thank you reply the mail.
Best regards,
KunYi

On 9 13 , 12 36 , "Dick Grier" <dick_grierNOSPAM@.msn.com> wrote:
Hi,

I have a WinCE 5 Industrial PPC (Psion) that exhibits this problem. Quite a
bit of testing makes me think that it is a driver/OS image issue, related to
power-down. If I do a hard reset, and reload all of my software (usually),
the DataReceived event in generated. However, often when the PPC is
subsequently powered down and then powered back up, data no longer is
receive (polling does not work, either). I "think" that the serial driver,
or something related, enters some (bug) state that causes this.

BTW, the earlier version, WinCE 4.2 did not show this problem. Although the
vendor has tried to help, nothing has been resolved, so far.

The same issue shows itself with my CFSerialIO dll (see my homepage) and
with the Serial class from OpenNETCF -- so, I think it is outside my
control.

BTW, it is possible that there is an issue with your code (as Chris
mentioned). For example, you should make sure that both DTREnable and
RTSEnable = True.

Dick

--
Richard Grier, MVP
Hard & Software
Author of Visual Basic Programmer's Guide to Serial Communications, Fourth
Edition,
ISBN 1-890422-28-2 (391 pages, includes CD-ROM). July 2004, Revised March
2006.
Seewww.hardandsoftware.netfor details and contact information.


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