Version 2.0 of this modification supports high score save for each game in thier own high score table. The high score is
saved on an nvram that is wired on to the board. The nvram used can either be a 48z02 or a DS1220 (both can be found
on the store page). My initial thought was to plug the nvram into one of the empty eprom sockets and just
wire up the w/r and CS lines. For several reasons that did not work but if you wire up the nvram to the 2114 ram (or make
an adapter) it will work. There are some creative ways to get the nvram on the board, if you think of any send them to me
and I will post them here.
Here is how the nvram (48z02/DS1220) needs to be connected:
NVRAM pin1 (A7) -> 2114 (4K) pin17 NVRAM pin24 (Vcc) -> Any +5
NVRAM pin2 (A6) -> 2114 (4K) pin1 NVRAM pin23 (A8) -> 2114 (4K) pin16
NVRAM pin3 (A5) -> 2114 (4K) pin2 NVRAM pin22 (A9) -> 2114 (4K) pin15
NVRAM pin4 (A4) -> 2114 (4K) pin3 NVRAM pin21 (/W) -> 2114 (4K) pin10
NVRAM pin5 (A3) -> 2114 (4K) pin4 NVRAM pin20 (/G) -> 74ls139 (5L) pin10
NVRAM pin6 (A2) -> 2114 (4K) pin7 NVRAM pin19 (A10) -> Any GND
NVRAM pin7 (A1) -> 2114 (4K) pin6 NVRAM pin18 (/E) -> 74ls139 (5L) pin10
NVRAM pin8 (A0) -> 2114 (4K) pin5 NVRAM pin17 (D7) -> 2114 (4K) pin11
NVRAM pin9 (D0) -> 2114 (4N) pin14 NVRAM pin16 (D6) -> 2114 (4K) pin12
NVRAM pin10 (D1) -> 2114 (4N) pin13 NVRAM pin15 (D5) -> 2114 (4K) pin13
NVRAM pin11 (D2) -> 2114 (4N) pin12 NVRAM pin14 (D4) -> 2114 (4K) pin14
NVRAM pin12 (Vss) -> Any GND NVRAM pin13 (D3) -> 2114 (4N) pin11
Here is a great example of an adapter courtesy of Slava Madrit
Here is a great example of an adapter courtesy of Mike Fuchs