Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A20 => Topic started by: olinuxino86 on January 04, 2014, 04:36:22 AM

Title: GPIO UEXT Stuff
Post by: olinuxino86 on January 04, 2014, 04:36:22 AM
Hi,

i'm new here, so a short introduction. hello :D i just got my A20 board two days ago and tried some images (arch,debian,linaro,android) all worked fine... nice work! unfortunately the mali stuff is pending and the solutions until now are very buggy... my hd videos never had more than 15-20fps with mplayer or vlc... but at least it worked. and i tried CedarX and the binary as well as the fbturbo driver...but all in all the rest is running very good :) incl. egles, bt, and other stuff.

after i figured out how to use all the gpio stuff theoretically works...in linux /sys/... and python( e.g. the blinking led... ) and now i want to try out my 3310 uext lcd.

i found some code from the imx233 on github to test it, but now i an stuck. https://github.com/OLIMEX/OLINUXINO/tree/master/SOFTWARE/iMX233/MOD-LCD3310

here its defined for the imx233 board
//MOSI -> bank[0], pin[20]
//MISO -> bank[0], pin[0]
//SCK -> bank[0], pin[24]
//cs - bank[0], pin[3]
//res - bank[1], pin[23]
//dc  - bank[1], ping[24]

the info of the lcd module, here the pins of the uext:
https://www.olimex.com/Products/Modules/LCD/MOD-LCD3310/resources/MOD-LCD3310-schematic.pdf

there are two questions
- is it easier to control it via gpio or serial? (the display can do both)
- the code is written for gpio, so its my favourite: is there something like the gpio-mmap.h for the A20? i have to admit that i can't write that hardware driver stuff... maybe somebody already did it and can help me :) of course i tried the code as it is, of course it could not work... i need to adjust the "pins" in the file, but i could not figure out how to do that here and get the right ones, and i tried it several hours. ^^

hopefully somebody can help me. thanks a lot.

greets

pete
Title: Re: GPIO UEXT Stuff
Post by: Mouchon on January 04, 2014, 03:11:01 PM
you can may be try with the following lib :-)
https://github.com/lephiloux/oa20gpiolib

This can may be help you.

A20 have also native spi interface that you can use but there is still an issue to use it in full duplex mode.
Title: Re: GPIO UEXT Stuff
Post by: olinuxino86 on January 04, 2014, 04:05:06 PM
ah thanks, i will try it...looks promising...hope i understand it ;)