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Flash ROM support

Posted: Fri May 31, 2002 8:18 pm
by Fencer128
Hello,

Does anyone happen to know - or know where to find - which flash ROMs are supported by different AMI or Award bios versions? I'm trying to find out in order to compile my own list of "drop-in" compatible ROMs for different motherboards. I don't necessarily have to use an identical ROM compared to that which comes as standard with a motherboard, but I do need 100% compatibility.

Thanks for your time,

Andy :wink:

Posted: Fri May 31, 2002 8:30 pm
by Rainbow
That differs between motherboard manufacturers :( They include support for Flash ROMs they use on their boards...
But generally - Winbond W29EExxx/W29C0xx and SST 29EE0x0 are very similar chips. Some other chips are 100% compatible with others (some are listed in UniFlash documentation (example: NexFlash Technologies NX29F010 = AMD Am29F010)

Posted: Fri May 31, 2002 8:44 pm
by Fencer128
Thanks for the quick response! (you seem to be answering a lot of questions!)

Given your reply above, if I have access to a particular bios *.bin image, is there any way of telling from the code what specific ROMs are supported?

I ask because I'm soon to be involved in supplying flash ROM IC's for specific mobos - and as you probably know - one ROM can cost more than twice the price of a rival's product with exactly the same specification.

Thank you once again for your prompt and accurate replies.

Cheers,

Andy

Posted: Fri May 31, 2002 9:37 pm
by Rainbow
I think that there is a way how to tell what chips BIOS support - it should detect them by manufacturer and device ID numbers (each is one byte) - as any flashing utility does. The supported IDs should be somewhere in the file - but where?

Posted: Sun Jun 02, 2002 6:44 pm
by Fencer128
Thanks Rainbow.

Could I pick your (or anyone else's!) brain another time please!... :D

If two ROMs are 100% 'drop-in' compatible with each other (ie DC characteristics, bus timings, pin assignment, sector structure/size and software commands are identical) then if one is supported in a certain manufacturers bios and the other is not - would you happen to know what the end result would be if one were replaced with the other. For example if the AMD chip you mention above were 'drop-in' compatible and was used to replace with a Nexflash ROM, and the bios only specifically recognised AMD device string. Would the bios work as before but only by assuming the new ROM was identical to the original, or would it need to be "forced" into treating the Nexflash as the AMD part. Sorry if this is very confusing - it's just that I'm trying to find a way to do the following things:

Ensure 100% compatibility between two different manufacturers ROMs

Ensure the bios will be able to read/write ESCD and DMI information correctly if the ROM were replaced

Ensure the Award/AMI/Uniflash utilities will continue to recognise and program the new ROM as they did the old (will most likely require me to draw up a list of supported ROMs myself, although AMIbios shows a list of supported ROMs and Uniflash has explicit source code - obviously! :oops: )

I need to be able to this so I have the greatest choice available for ROM parts. Some ROM parts are very expensive compared to others in the UK (also suppliers usually only offer a limited range of manufacturers for sale). Given the compatibility issues highlighted in your posts to me I find it difficult to see how companies such as badflash.com and flashbios.org can offer their services without stocking parts from nearly all the flash ROM manufacturers (both discontinued lines and current production). This may indeed be the case but I would have thought it possible to narrow the list somehow?

Thank you again for your intelligent replies,

Andy

Posted: Sun Jun 02, 2002 9:34 pm
by Fencer128
No ideas anyone? - I realise my questions are getting more obscure!

If anyone has tried something like the above or knows where such information exists, please could they give me a pointer?

Thanks,

Andy