Newbie questions before I fry my board

[sanzoghenzo]

Hi all! just ordered a olinuxino a20, and I'm new to this devboard world
Since I cannot find much documentation about this board (but features are so good that can fit my projects) I would like to ask some questions:

• I plan to build an "expansion card" to interface olinuxino with an arcade cabinet that has his PSU that supplies 12V and +/-5V on some pins of the jamma fingerboard ("the interface"). What's the best method to provide power to the olinuxino? can I feed 5V into one of the enabled GPIO pins or should I route the 12V signal to the power socket? the thing is, it wolud be great if I can build a duino-like-shield that simply plug to gpio socket(s). do I have some chance?
• I red about GPIO ugly driver for A13, but I saw here that gpio-sunxi implementation changed (for good). Unfortunately in Kconfig it states that it depends on arch_sun3i,arch_sun4i or arch_sun5i. Does it work with A20 (arch_sun7i) also? It's just a matter of adding the arch on kconfig or is it something more difficult?
• is there a way to acces to audio out from the gpio connectors? Just like the power, I have to take the audio out, amplify it and than route it to the fingerboard.

Thanks in advance for your time!
Cheers from Italy

[XFer]

I've just ordered an A20 board so I reply for having read docs, not from 1st hand experience.
Anyway I think you have to supply 12V to the power plug.
I don't think Gpio are for providing power to the board.
And, I don't think they can output audio, either.
A20 has I2S audio out if you need digital audio out and analog out 44/48khz from stereo headphone plug.
Also consider that Gpio are not supported yet under Linux (no kernel support)

[sanzoghenzo]

I've just ordered an A20 board so I reply for having read docs, not from 1st hand experience.

Thanks Xfer, you confirmed the same thing I discovered running through the (poor) documentation.
For the audio I can solve with a DAC (even though I'm trying to keep my board simple).
For the power, I assumed it's like arduino, where you can feed a steady 5V (or 3.3V for arduino due) directly from the pins, bypassing the board's voltage regulator.
I hope GPIO support will come soon because is the main reason I bought this gorgeous board!
Thanks again,
have fun with your board!

[XFer]

Hi,
I come from Arduino, too.
These Olinuxino boards are quite different, expecially regarding power supply and Gpio.
Please let's keep in contact about audio: for my project I'll make do with integrated DAC for now, but I'd like to switch to digital audio output + external DAC next (I'm designing a MIDI expander box so audio quality is important).

Fernando