[E3-hacking] E2 hackery & coding

[Matt Evans]

Hola DG!

On 13 Nov 2008, at 12:02, David Given wrote:

> Matt Evans wrote:
> [...]
>> Yeah post it! :)  Prex sounds cool, get anywhere fun with it?  I got
>> about 5 lines into uclinux booting and ... Well, it's covered in dust
>> now. :-/
>
> Here you go.
> [snip]

Great, thanks!  Will have a play with that, looks fun. :)

> I never even knew PBL *did* support the SM card --- it would be  
> awesome
> if we could make it work, if my E2 had a SMC socket, if my E2 still
> worked... but yes, I quite agree about SMC vs MMC. MMC and SD are so
> wonderfully simple to drive that they could almost have been designed
> for homebrewers...

 From distant vague disassembly memory, the NAND routines take a  
"struct nandDevice *" and all of the FTL and IO stuff indirects  
through this.  I *think* I remember the routines using this to switch  
the GPIO to /CS the internal NAND or /CS the SM card, too -- so There  
Is Some Code To Support It But It May Not Work.   (I can well believe  
it was just built that way, perhaps an internal build would boot  
NastyOS from an SM card if you held down something, could be just that  
trigger would've been removed in shipping vsns?)  I had some code in  
e2-monitor that would read/write the SM card (just raw sectors) but my  
enthusiasm for dealing with the FTL/bad blocks etc. severely waned so  
I took it out. ;)


Cheers,


Matt

PS: You got a scope?  The EXP serial port's buffered through a couple  
of transistors IIRC, your bare serial port on the MCU may still  
work...maybe? :)