[ale] Network access to serial devices

[Christopher Fowler]

On Mon, 2006-01-16 at 17:51 -0500, John Mills wrote:
> > That would be awesome.  We used to write software at Computone to do
> > this.  We had to write a driver and that driver would enumerate COM
> > ports on the WinX side.  The problem we faced was that many apps
> would
> > not see pass COM4.  Good luck.  Not much free in that world on the
> Win2K
> > side.  It would be cool though.
> 
> Free would be nice, but there are $150 solutions with 30-day trials
> that
> should be fine for a single-station setup. Can't afford to scr#w
> around
> long for $150.
> 

The main problem we had when doing this was configuration of tty
settings.  On the Linux side depending on how you are doing things you
may not be able to set termios settings on the fly for the serial port.

On the Win2k side you'll need a method to transmit tty settings outside
of the data stream.  I think we did this using a TCP OOB message. We
would transmit the new settings to the serial port on the embedded
device.  The embedded device would then issue the ioctl().  I don't
think netcat can support anything like that.  You'll have to keep this
in mind when things might not work.