Nick, you are right on in that the flashboard needs a bootstrap program (i.e. like grub or lilo on x86 computers). Certainly, this bootstrap need not change very often, but change it does. It is the bootloader that causes so much grief. If this part is flashed incorrectly or is incomplete, the whole machine will not work. That is why having a separate external programmer is so important.
Also, space on the flashboard is quite scarce. The current HP-designed flashboard has four chips on it along with some other SMT components and even that is crowded....
Nick L wrote ..
> Mark,
>
> Is there any worth in adding a small chip which could be used to
> bootstrap the machine if the flash was completely empty? I am
> thinking that the code would be fairly simple - check for presence of
> bootable entries on the flash, and then execute as appropriate after
> moving itself out of the way. If no code exists, or the user was
> pressing a certain key combo, it could interact with the user via a
> terminal on the serial port...
>
> The programming of this chip would never need to change, but it could
> provide a way to recover from experimentations gone wrong... I am
> thinking that this would make programming new kernels etc via the end
> user a huge amount easier, and also provide for a recovery path
> without requiring a programmer.
>
> Could this be achieved by masking off a portion of the ROM for
> strapping purposes, rather than having a separate chip?
>
> Is this a complete flight of fantasy on my part :-) ?
>
> Cheers,
> Nick.
>
> --
> "Why don't you go and bother that nice Ms Rowling?" - Terry Pratchett
> http://www.chiark.com
Received on Tue Jun 21 2005 - 08:15:20 EDT
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