Subject: [E3-hacking] E3 Memory Map?

From: "David J. Singer" <[email-masked]>
Date: Mon, 15 May 2006 18:21:13 +0000

Is the E3's memory map documented anywhere? I've had a quick look back through 
the list archives and it doesn't appear on the Wiki anywhere...

I guess before I get too ambitious with the E3 I'd like to know what lives 
where.  Is it possible, for example, to wipe out the PBL boot loader by 
mistake? And where does the Amstrad firmware fit in to all of this?  I'm 
still using the example 'linux.pbl' file (or a derivative thereof) from 
http://the.earth.li/pub/e3/2.6.15/ .  Is it possible to wipe out the Amstrad 
firmware to gain more space for custom stuff?  

-- 
David J. Singer
[email-masked]
"Time flies like an arrow, fruit flies like a banana"

---

From: David Given <[email-masked]>
Date: Mon, 15 May 2006 19:18:37 +0100

David J. Singer wrote:
[...]
> firmware to gain more space for custom stuff?  

The answer to that is both yes and no; the E3 has two flash chips. There's a
NOR flash, that's memory mapped, which contains the boot loader --- it's all
of 64kB long. And there's a NAND flash which is *not* memory mapped that
contains the actual software. This is copied into main memory to execute there.

So far there's no (released) way of booting a Linux kernel out of the NAND
flash, and the NOR flash is far too small to be useful (plus it's strongly
recommended you don't touch it in case you toast PBL and brick the device), so
all you can really do with the NAND flash is to use it as a filesystem --- and
frankly, using a USB key is easier although a bit slower.

- --
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|  [email-masked]    | scintillating, many fauceted scarlet emerald..."
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