From the previous log it is mentioned that only Mapper 0 and 4 games can be put into these consoles.
However, some of the games in the 400-in-1 console contains Mapper 4 that are converted from Mapper 2 such as Jackal. Those games are running without CHR-ROM and only CHR-RAM instead.
Earlier on, when such games are inserted into the console with the custom menu, it gives a black screen, or garbage output.
Then, checking how did the game selection in 400-in-1's original menu works, it is noticed that there is a specific sequence, and a specific range of number that gives these converted games a correct tile output.
I have rearranged the loading of these OneBus registers ($401x) following the ones in that original menu:
jumpToProgramInRAM:
lda _zR410A
sta $410A
lda _zR410B
sta $410B
lda _zR4100
sta $4100
lda _zR4105
sta $4105
lda _zR4106
sta $4106
lda _zR4107
sta $4107
lda _zR4108
sta $4108
lda _zR4109
sta $4109
Since these games does not run on CHR-ROM, the configuration of the OneBus registers at $201x are not involved. However, the bottom nibble of the $4100 must be between 0x04 and 0x0F for these games to work I'm not entirely sure why, and it works on both the emulator, and on the handheld itself.
Well, here it is - at least it loaded correctly! :D
Note: I have tested other Mapper 0 games with only CHR-RAM. It doesn't work at all on both the EmuVT and the handheld too.
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