[gta02-core] LCM schematics

[Werner Almesberger]

Luke Duncan wrote:
> -  Any preference to what spi port we connect the LCM to? It is connected to
> SPI1 right now.

I'd just use any GPIOs that look friendly and bit-bang the thing.
We'll need one SPI for WLAN and the other for the acceleration sensor,
which are both high-throughput devices and shouldn't have to share the
bus. In particular, the acceleration sensor may act unpredictable if
sharing.

> -  Signal filters. I'm not sure if OM had a method to their madness when
> connecting signals to the filters (RP6xxx)

Hmm, dunno. Staring at the Gerbers, I couldn't quite figure out the
pattern. Maybe we'll find out when we get to the layout.

However, there's a bigger problem: if you look at the "VD Pin
Descriptions at 16BPP" on page 15-18 of the 2442 manual, you'll see
that some of the VDx lines are skipped. So you connect as if it was
8:8:8 RGB and leave out the least significant bits which aren't
there.

You can use the GTA01 schematics as a reference. There, the LCM was
connected directly to the CPU as well.

- Werner