We do serial differently.

[Gary Jennejohn]

On Thu, 19 Oct 2017 13:32:47 +0200
Gary Jennejohn <gljennjohn at gmail.com> wrote:

> On Thu, 19 Oct 2017 11:03:46 +0100
> Bob Bishop <rb at gid.co.uk> wrote:
> 
> > Hi,
> >   
> > > On 19 Oct 2017, at 05:25, Zaphod Beeblebrox <zbeeble at gmail.com> wrote:
> > > 
> > > How does FreeBSD do serial differently than Linux or MacOS or Windows?    
> > 
> > Quite likely only in the defaults when a port is opened.
> >   
> > > Now... this isn't _exactly_ serial, but the serial that is emulated by the
> > > arduino driver in ports.
> > > 
> > > The issue is that running the arduino IDE works (and it boots with the
> > > loaded code), but then running 'pronterface'  fails to connect --- looking
> > > all-the-while like one-way communication.
> > > 
> > > I see someone else basically having the same problem and claiming that
> > > hacking a trace (that affects the DTR response) on the arduino fixes it for
> > > FreeBSD (see https://plus.google.com/+MiroslavPrymek/posts/6TDdbuoNhzH )...
> > > 
> > > Given this information, can I stty my way out of this problem?  Can I make
> > > a small modification to pronterface?    
> > 
> > stty -clocal ...
> >   
> 
> Hmm.  The description of clocal in stty(1) is incorrect.  It states
> that clocal is without and -clocal with modem control.  It's reversed.
> 

My error.  After looking at the stty source I realized that the
man page is correct.  To turn off modem control use stty clocal.
That results in tcsetattr(3) setting the CLOCAL flag = ignore
modem status lines.

> > might help.
> > 
> > All implementations of virtualised serial ports should (IMHO) provide a software ___breakout box___ which is the only sure way of diagnosing this sort of problem.
> >   
> 
> -- 
> Gary Jennejohn


-- 
Gary Jennejohn