low level boot process and too many questions!

[codifies]

what exactly is the boot process for the a20 ? - does the chip look in one place or multiple for u-boot?

Ideally I'd like to boot directly from SATA but I'm guessing its either embedded flash or sdcard only depending if the board has embedded flash or not?

I've had bad experiences on a number of different devices with sudden power loss and SD card corruption - sometimes quite subtle corruption but enough to bork a boot process (typically) - might still have some applications that for various reasons batteries even for backup are out of spec.

Can I assume that if an SD card is only ever mounted RO and boot immediately hands over to SATA then there is likely to be more robustness even in scenarios where there is sudden power loss?

If using a LiPo pack can information like %age power left be retrieved ?

anyone got any typical endurance figures for say a 10" panel with light to moderate cpu usage, using the largest Olimex LiPo pack?

I expect if driving even a 10" display and A20 + WIFI etc and I want 6-8+ hours then I'll be looking for some other LiPo charging module rather than the one built in ?

This A20 board is so tricked out its like I spec'd it in a fevered dream and I'm still sleeping  -  no wonder I'm inspired to build my own Linux (ie NOT Android) tablet! :-D

[JohnS]

The whole AW family is covered - but only as far as discovered/released - in AW doc and people's findings on www.linux-sunxi.org

Use its search (words like boot) and go reading

You can boot via SD and not even mount it, I think.

I expect LiPo will last hardly any time if powering LCD - if it indeed can do that.

John

[codifies]

well thats a *lot* more flexible that I expected ... sadly still not a bios setup type program like on x86 nor luxury like grub - but i'm just being spoilt...

[dave-at-axon]

I expect LiPo will last hardly any time if powering LCD - if it indeed can do that.

It will depend on the LiPo size of course but I got 6+ hours from a 6600mAh LiPo with the LCD on at full brightness sitting at the main screen. I am running Android on my A20.

I suggest you put a battery on your system, even a small one and then detect when on battery and do a proper shutdown. Android does this for you.