Project: Building a universal flash adaptor.

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stonent
BIOS Rookie
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Joined: Tue Jul 16, 2002 6:10 am

I'm working on a cheap device with little to no hardware to flash chips. Here is what I've got as an idea and would appreciate any input.

Take a piece of perf board or similar and put a wire-wrap 32pin socket into it. The point of the wire-wrap socket is the long wires will extend long enough to allow it to fit in a motherboard socket and hover above it.

Next to that socket will be a PLCC socket for flashing plcc chips. And finally a piece of ribbon cable with a PLCC socket wired in reverse so that it could snap over a soldered plcc bios. (Taking into accound that I'll have to lift the voltage pins on the chip before flashing)

I've already noticed that I'm going to have to take a dremel tool and remove the keyed edge from the PLCC socket to allow it to fit an upside down plcc chip.

One other idea that I had considered is a DIP to Ribbon cable adaptor. I found a 40 pin one from an old 8088 accellerator board I had a long time ago. (the 40 pin thing plugs into the cpu socket and the ribbon cable has a 40 pin header on the other end that goes to the accellerator board). There are many bent pins on it so ideally a new one could be procured if I could find a source for it.

My priority for this device is cost. So there won't be any real electronics, just a place to put the chips.

One question is, do the boards really care (other than voltage) what they are flashing? If I had say a 1998 board with a 128k chip and adapted a 512k chip into the socket would it detect and flash it, or do some of the newer chips require different hardware (such as the firmware hub intel chips?)

Any comments or suggestions are appreciated.
edwin
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Rainbow
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Firmware Hubs and LPC Flash ROMs are not compatible with standard Flash ROMs. Most boards that came with 128KB chips will not flash 256KB chips because the topmost address line is often not connected to the socket (however this is not true for all boards - PC Chips M726, for example, has 128KB chip but flashes 256KB chips without any problems).
Patched and tested BIOSes are at http://wims.rainbow-software.org
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stonent
BIOS Rookie
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Interesting considering that I have been using an M726 for flashing. The other link posted I have read before, but my purpose was something that didn't require making a pcboard.
edwin
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Yep, but you might consider building one after all, as you've seen the limitations of the original thought.
edwin/evasive

Do not assume anything

System error, strike any user to continue...
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