Re: [lcd4linux] GPO circuitry

[Aragon G. <ar...@ph...>]

| By Michael Reinelt <re...@eu...>
|                                          [ 2004-02-15 19:31 +0200 ]
> Should be no problem in hardware, but at the moment this is not 
> supported in software. AND there's another problem: Some commands 
> (clear, init, character define) go to _both_ displays at the same time, 
> just by rising _both_ enable lines.

Ah ic.  Yes, that will be a problem if this extra circuitry were added.  You
wouldn't want to send your init, clear, and character define to the
CD4514s... ;)

I'm very keen to do this for myself though.  A 20x4 display is kinda small,
and I don't like the idea of loosing software controlled backlighting with a
40x4 display.  Is it complicated to change those commands to address each
display one at a time?  Or maybe make it user configurable?

I'm thinking all the commands that address both displays together are ones
used relatively infrequently?  Consequently, addressing them one at a time
shouldn't have a noticable performance hit?


Thanks,
Aragon