Here's the schematic for the robot controller (WIP):
http://www.marcansoft.com/uploads/images/euskalbot_sch3.png

And here's the current board:
http://www.marcansoft.com/uploads/images/euskalbot_brd7.png

Note that we're making the boards by hand. It'll be a two-layer board,
but we're not exposing the back side - it's all ground plane. The few
signal traces that are drawn as being part of it are wire jumpers (I'd
have used a separate board in Eagle, but I'm using the freeware version
which only supports two layers). Also of note, the partly
surface-soldered DIL L293D chip (ground pins go through, all the others
don't. Minimizes drilling and simplifies back layer) ;)

Here's the bootloader (WIP, but works very well right now).
http://www.marcansoft.com/uploads/botload1.0.zip

Apologies for the comments in Spanish, for those who don't understand
them. I'd usually comment my code in English, but I'm interested in the
attendees being able to investigate the source themselves if they want,
and not everyone knows English around here.

Here's a packaged Windows version of the host-side loader, so you don't
have to install Python and the required modules. This also has some
mostly insignificant bugfixes (I'll upload the 1.1 source later)
http://www.marcansoft.com/uploads/botload1.1.zip

The bootloader has a few advanced features. Most notably, it's capable
of handling a lot of abuse in the reset vector, and doesn't necessarily
require NOPs or any other kind of accomodations. There are some things
which may not work, like a GOTO that lands on the boundary between
vectors or branches from main code to the vectors, but I have a feeling
it's one of the more advanced vector-patching engines. The bootloader
also includes code to leave the UART running and possibly enable
interrupts if requested through a magic number, which allows for simple
programs to support resetting back to the bootloader with no user
intervention, when something comes in through the UART, with no extra
handling code in the user program.

-- 
Hector Martin (hector@marcansoft.com)
Public Key: http://www.marcansoft.com/marcan.asc

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