The amount of video SRAM of any famiclone can be upgraded with one UM61256, UM62256 or compatible Cypress or Mosel chips.The wiring from chip to famiclone's pins is done like this:
Memory/Famiclone pinout
1.A14 -> 30.+5V
2.A12 -> 55.CHR A12
3.A7 -> 50.CHR A7
4.A6 -> 19.CHR A6
5.A5 -> 20.CHR A5
6.A4 -> 21.CHR A4
7.A3 -> 22.CHR A3
8.A2 -> 23.CHR A2
9.A1 -> 24.CHR A1
10.A0 -> 25.CHR A0
11.I/O1 ->26.CHR D0
12.I/O2 ->27.CHR D1
13.I/O3 ->28.CHR D2
14.GND ->16.(1.) GND
15.I/O4 ->29.CHR D3
16.I/O5 ->60.CHR D4
17.I/O6 ->59.CHR D5
18.I/O7 ->58.CHR D6
19.I/O8 ->57.CHR D7
20.CE# ->56.CHR / A13
21.A10 ->53.CHR A10
22.OE# ->17.CHR/RD
23.A11 ->54.CHR A11
24.A9 ->52.CHR A9
25.A8 ->51.CHR A8
26.A13 ->30.(31.) +5V
27.WE# ->47.CHR/WR
28.VCC ->30.(31.) +5V
UM61256 is a 256k high speed CMOS static RAM organised as 32K x 8.
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30.= 31.= +5V CONNECTED TOGETHER
1.=16.= GROUND CONNECTED TOGETHER
41.=46.= EXP CONNECTED TOGETHER
Other notes: if original Famicom has the same pinout as famiclone, it can be upgraded too. I will try to make the upgrade even for NES.
Upgrade famiclone's RAM
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