Introduction
"To take the Sideways RAM cartridges to their final design (I shouldn't say final as the RAM size can grow quite considerably)". Well I couldn't resist! I took version 3.5 and swapped out the 62256 memory for an AS6C4008 and added a hex switch to select between the sixteen pairs of banks.This harks back to the late 80's early 90's when I designed a switched eight image EPROM and 2019 when I designed virtually the same thing as an AP6 plug in module..please see my 'Electron' and 'My Acorn Revival 2019' pages to read more about them.
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The SRAMextreme bare board and basic components added.
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The rear of the board with the hex switch socket soldered in and the front of the board with the RAM and supporting chips inserted.
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The hex switch in place.
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Testing banks 4, 5 and 13. Banks 4 and 5 can be switched sixteen times to load and use up to 32 ROM images - two at time!
If you would like to build one for yourself, everything you need including the Gerbers, BOM and Circuit Diagram are here - Battery Backed SRAMextreme.