[Fwd: RE: [U-Boot-Users] Incorrect flash ids?]

Wolfgang Denk wd at denx.de
Tue Jan 13 21:09:02 CET 2004

In message <20415. at www.orkun.us> you wrote:
> Well, there is no end to it. In my previous job, hardware engineer decided
> to use 64bit bus for flash so we had 4 of them to make 64bit bus(MPC755).
> So, the 32 bit ones is not enough to compare all 4 anyway.

It is. You can read 64 bits in two chunks of 32 bits each.  There  is
actually  little chance that the upper and the lower half of your bus
will use different flash chips.

> Another perfectly valid (but unusual) scheme is to map 4 devices each in
> byte mode. That 4 byte ID read would be different that the stored one if
> you wanted to compare them bus wide.

No problem. I think there are boards doing exactly this.

Best regards,

Wolfgang Denk

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