Re: Win32::Commport, SerialPort stopbits woes

"ben_raymond" <ben_raymond-/[email protected]> Thu, 03 Mar 2005 23:37:10 -0000
Newsgroups gmane.comp.windows.ce.freeware
Message-ID <[email protected]>

> > I'm aiming to get my PocketPC to talk to a Dallas one-wire network.
> > However, I'm failing at the first hurdle: getting serial
> > communications working under PerlCE. I don't seem to be able to change
> > the number of stop bits.

> I remember some strange behavior of the IPAQ serial port driver..
> Try ignoring the error and/or change the masks.

I did try that (changed the mask to 0x701) - so $PortObj->stopbits(1)
would then apparently work, and write_settings came back happy. But
the actual stop bits setting of the port doesn't change (as reported
by turning $Babble on in CommPort.pm) and if you try and write
something to the port, it would get to the CommWaitEvent call in
write_done and then wait forever.  Conversely, if I leave the stop
bits setting unchanged (at 0) then CommWaitEvent passes OK and
everything appears to be working (but of course I need one stop bit to
talk to my external hardware). I am guessing that forcing the stop
bits mask ends up causing a failure to recognise an empty output buffer. 

Sounds like a hardware issue with the IPAQ, maybe I will try different
hardware if I can get hold of something.

Ta
Ben