[sdiy] Multiple LCD connection sanity check please

[Andre Majorel]

On 2011-01-11 16:19 +0000, Tom Wiltshire wrote:

> If we assume 2x40 displays, that's a maximum of 8x80=640
> characters to refresh all the screens. If I wanted a refresh
> rate of 20Hz, I'd need to send 12800 characters per second. So
> you're right, I'm potentially out by a factor of 6 or so.
> Still, I think I might wing it and see how much of a problem
> this is. I doubt I need to refresh the whole of every screen
> that often. Mostly I'd be updating values on one line of one
> or two screens.

The routine could drop intermediate changes. On some LCD, the
pixels take a long time to change states and if you try to
refresh more than a few times per second, all you get is a blur.
The Digitech TSR-12 has that problem in diagnostic mode.

-- 
André Majorel http://www.teaser.fr/~amajorel/