So finally I think it is:
Code:
$8001 $8000 (mask: $8001)
[......wP] [PmvPPPPp]
|| ||||||||
|+----+||+++++- 16K/32K PRG bank (p ignored in 32k mode)
| |+------- PRG mode (0=32K,1=16K)
| +-------- mirroring (0=V,1=H)
+--------------- 1=CHR-RAM is write protected
On power up & reset, both registers are cleared
In order to dump it, you need to
1) Short the capacitor
2) try this script (warning - I don't see in FCEUx source any mapper number that follows this description, so probably new mapper need to be assigned & emulator modified)
Code:
board <- {
mappernum = 255,
cpu_rom = { size_base = 2097152, size_max = 2097152, banksize = 0x4000 },
ppu_rom = { size_base = 0, size_max = 0, banksize = 0 },
ppu_ramfind = false, vram_mirrorfind = false
};
function cpu_dump(d, pagesize, banksize) {
for (local i = 0; i < pagesize; ++i) {
cpu_write(d, 0x8000, (i & 0x1F) | (1 << 5) | ((((i >> 5) & 1) << 7)));
cpu_write(d, 0x8001, (i >> 6) & 1);
cpu_read(d, 0x8000, banksize);
}
}