I have a fairly extensive 1-wire network that works pretty well (thanks, 
Paul!) and now I have a handful of 20 character VFD alphanumeric displays that 
I want to add to it.  There are some VFD displays that have parallel 
interfaces that mimic 44780 type LCD controllers, but these are not those.  
The good news is that these displays have ordinary RS232 serial interfaces (RX 
only - the displays have no TXD) and understand ordinary ASCII.  Most printing 
ASCII characters display as you'd expect, and there are few ASCII control 
characters and escape sequences for controlling display parameters.

  How to interface these to 1-wire?  AFAIK there's no such thing as a "1-wire 
to RS232" interface already, so I'm thinking of just taking a little AVR chip, 
like an 8 pin ATtiny device, and programming it to do the job.  There are 
already some AVR 1-wire slave libraries, like the one by Matthias Urlichs 
(http://github.com/smurfix/owslave), and with that it'd be a fairly simple job.

  Is there a better way?  Or has somebody already done this?

  If not, then there's the question of what kind of 1-wire device should my 
gizmo emulate?  Ideally it'd be something that OWFS could talk to without any 
modifications.  I suppose I could write enough code for the AVR to emulate an 
HD44780 and fake out one of the existing LCD drivers in OWFS, but that seems 
like a lot of extra work.  Plus AFAIK the existing LCD interfaces (like the 
Hobby Boards one) use general purpose parallel output ports to bit bang the 
44780 prototcol.  That's super slow over 1-wire.  I'd much rather be able to 
send the display straight ASCII text a whole byte at a time.

Thanks,
Bob


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