Making a ram card is nearly identical to the rom card. One difference is the R/W line is added so data can be written to the ram. Another difference is the CS pin, on the 8k static ram there is a !CS1 and a CS2 select pin. I ran the output of the 74LS85 directly to CS2, as it is active high, and then ran VMA into the single gate inverter and tied it to !CS1 and !OE (output enable).
Note: This card can be simplified by running VMA into the comparator (like the rom card does), and just grounding !CS1 and !OE. This will eliminate the need for the single gate inverter chip.
The bank selection works the same as the ROM card.
--> A slight deviation from the plan, Another Ram card
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