[E3-hacking] E3 Memory Map?

[David Given]

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David J. Singer wrote:
[...]
> 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?  

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.

- --
+- David Given --McQ-+ "Gaping from its single obling socket was
|  dg at cowlark.com    | scintillating, many fauceted scarlet emerald..."
| (dg at tao-group.com) | --- Jim Theis, _The Eye of Argon_ (spelling
+- www.cowlark.com --+ original)

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