27c010 plcc -> 28 pin rom pcb

Upgrade or replace the ROM.
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microman
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27c010 plcc -> 28 pin rom pcb

Post by microman »

I am looking to upgrade the TOS in my 520STFM, it has a C103253 Rev 1 motherboard with 2 x RP231024 mask ROMs, (28 pin)

It would seem to me fairly straight forwards to use a pair of small adapter boards 28 pins -> plcc32 socket tracked for a 27C010 EPROM or ATF39SF010 are there any such designs arround or are there any issues (height etc) with doing this. I note that there are several pcbs avaialble that plug into both chips so are motherboard specific.

Thanks

Peter
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rubber_jonnie
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Re: 27c010 plcc -> 28 pin rom pcb

Post by rubber_jonnie »

Given the ROMs are under the PSU on that mainboard, you might find yourself a bit short on space, especially if your adapter boards will be plugging into sockets, and will have sockets on themselves.

I think you'd be just as well adding the extra 4 sockets and using 27C256s. Just my opinion.
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Re: 27c010 plcc -> 28 pin rom pcb

Post by exxos »

Adapters under the power supply generally do not work because of height restrictions. As RJ says, 6 chip TOS is probably the simplest method.
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