If I wanted the first Ram chip to have battery backup, is it just a matter of connecting the power pin from the battery?
Sorry for the newb question. I just have a bunch of SOROM boards I'm trying to convert to SXROM boards.
Thank you for any help.
Yes, you will need to remove the pin of the RAM chip which does not have backup from VCC line and tie it to the "VCC" pin of the other RAM chip - which is as I called it before "VRAM VCC", that will be at +5V when the circuit is used, and on the battery's +3V when the circuit is powered off.
Also keep in mind that SXROM has 32kb WRAM while SOROM only have 16kb. It could be all right if you develop your game using "only" 16kb though.
Thank you, worked like a charm.
Yes, I have moved the smaller sized ram chips off the board and replaced them with one 32K chip. I also have cut the traces to the 2nd chip and mounted the hex inverter there and ran jumper wires on the back. I think this is much cleaner than having jumper wires hanging off connecting to the hex inverter as is the norm with NROM's.
Thanks again.