Use Of Serial Port

[G0GMK]

I have searched everywhere and cannot find what I need to know. Is it possible (with the right code) to use the serial port for anything except debugging ??
What I would like to do is use my gp2x as part of an amateur radio ATV repeater. As I need a bucket load of I/O my idea was to use the serial port to talk to a PIC to give me some I/O and then extend from the PIC with I2C I/O expanders.
If not possible with the serial port, any other ideas ??

Presently the repeater is all written in assembler (by me) and runs on a single 16F877A but needs lots of peripherals to generate Video, generate audio, do OSD overlays etc and is a pain when updates are needed as no one else in our club 'talks' PIC assembler

TIA Dave

 

[rokdcasbah]

i don't know enough about what you're trying to do, but here's a couple of links (that you may already have seen)

http://wiki.gp2x.org/wiki/Serial_cable
http://www.gp32x.de/board/lofiversion/index.php/t32700.html
http://www.spritesmods.com/?art=gp2xgps

it's rs-232 obviously, and you're right about it mainly being used for debugging. but i think it's pretty flexible, at least that third link seems to imply that. i guess you'd have to write in such a way that the extra communication happening over the line would be ignored. i really don't know enough about these things though. hopefully someone will have a more accurate answer for you.

 

[Mudi]

I believe you can get the USB slave to act as a serial port with the g_serial module in the archive somewhere, which would make that quite a bit easier, and yes I think you can make the serial port do other things, but I'm no expert on that...

 

[cheap-plastic]

Sprite_tm has connected a serial gps to his gp2x. You can find the details here: http://www.spritesmods.com/?art=gp2xgps

QUOTE
The serial output is damaged a bit, because the gp2x-menu tries to read from the serial port, too, but the NMEA-strings are recognisable.

 

[Squidge]

With Linux running, you can easily have input to the gp2x, but output is more complicated, as it's Linux's root console. You have to stop it from blabbing first.

For your project, I would have thought a GP32 would be a better platform. It has two dedicated serial ports (which can also be used as GPIO), as well as I2C on the ext connector.

 

[G0GMK]

Thanks for the links guys, I had already seen them.
Squidge, I have an original (non lit) GP32 here but the reason why I was thinking of the 2x is the video facilities (ATV = Amateur TeleVision). If I used the GP32 I would still need all of the peripherals that I am using with the PIC.
The USB route might be an idea, I think I could then use one of the USB PIC's as an HID device for the interface.
Other option is carry on using the GP2X for games
Thanks Again. Dave