CPS 3 SIMMS

PCB problems and fixes
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VIDEOTRONICS
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CPS 3 SIMMS

Post by VIDEOTRONICS » March 22nd, 2019, 9:18 pm

hi

has anyone soldered memory chips on a 32mbit simm etc smaller ones to convert to 128mbit
i presume the memory stock pcb is same for all sizes. 32,64 128?
can it be done?

any advice
and source of chips???

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leonardoliveira
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Re: CPS 3 SIMMS

Post by leonardoliveira » March 22nd, 2019, 11:37 pm

The problem would be source the chips to repair the faulty simms. Maybe using the smaller (32MB) ones to repair faulty larger ones is a valid idea?

Half of the chips are of the inverse pinout type which are complicated to source.
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nem
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Re: CPS 3 SIMMS

Post by nem » March 23rd, 2019, 12:37 pm

It's been done. There's a thread on Arcade-Projects:

https://www.arcade-projects.com/forums/ ... 28mb-simm/

64mb sticks are unique though and can't be made with 32mb / 128mb sticks.

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Re: CPS 3 SIMMS

Post by leonardoliveira » March 25th, 2019, 5:05 pm

64MB simms are meant to hold CPU code, they don't have traces to mount chips on the back side of the board. The CPS3 refer to the simms meant to hold data as "DMA simms" (the side with six sockets) and the side with two are "PRG simms".
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