Cart DB #153: Game Genie [blob]

Notes for chip search:

Use "+" as delimeter for all fields (except "cart name", where space is used); if many values are entered, all of them must appear in the cartridge then; case is not sensitive
"Mapper" is the actual mapper used by this cartridge hardware (might not match the one at wiki.nesdev.com, as at the moment I was analyzing this cartridge, there was no mapper assigned to it, so I had to assign my own number for testing)
"Original mapper" is the mapper used by licensed version of this game (for multicarts, it refers to mapper of the inside games, so 0+2 means this cartridge can run NROM+UNROM games)
Order in which you put values doesn't matter (you can write 7400+74138+7400 or 7400+7400+74138 to search for a cartridge that contains at least two 7400 chips and one 74138
Some chips (like PAL16*8) appear in cartridges as 16V8 or 16L8, so be sure to check both posibilities
Same goes for memories - type 27F080 to search for 32 pin memories, 27512 for 28 pin with two chip enables or MASKROM_1M_DIP28 for 28 pin with one chip enable
Same goes for mappers - some examples: AX5904(MMC1), AX5202P(MMC3), PT8154BM (9112MMC3), AX5208C(VRC4), 23C3662(VRC2)
Good news is that you can use wildcards, so 74139+*MMC3* will search for any cartrige that has at least one 74139 and MMC3 chip in any version

Name	Value
IC1	DIL48
C1	1u
C2	?
CART	NES_CART
CONS	NES_CART
TP1
TP2
TP3
TP4

Name

Value

IC1

DIL48

CART

NES_CART

CONS

NES_CART

TP1

TP2

TP3

TP4

Game Genie controls PPU-A13, /ROMSEL and M2 of the slave-cartridge slot. All other pins are pass-through. Additionally CPU-D0..7 are connected to GameGenie via resistors as shown below. I believe those resistors are used to protect against bus conflicts when cartridge ROM hasn't stopped driving dat bus yet but Genie starts driving bus with data to be replaced. [code] CONSOLE SLAVE CART M2 ------------470R-------+--- M2 .-------------. | | 4kB GENIE | | | PRG-ROM /OE|--GND | | /CE|----------------------+ | `-------------` | | .-------------. | | VCC,GND,/RESET --| DIL48 |-+-|<-+ /ROMSEL --| GALLOB |-------- /ROMSEL PPU A13 --| GENIE |-------- PPU A13 unused pins (22,30) -| CHIP | `-+-+-+-+-+-+-` 200R | | | | | CPU D0-D7 ----+-|-|-|-|-|---------- CPU D0-D7 CPU A0-A14 ------+-|-|-|-|---------- CPU A0-A14 CPU R/W --------+-|-|-|---------- CPU R/W PPU D0-D7 ----------+-|-|---------- PPU D0-D7 PPU /RD ------------+-|---------- PPU /RD PPU A2,4,5,6,7 --------------+---------- PPU A2,4,5,6,7 other lines ------------------------- all other lines [/code] My question is: what happends if Genie is going to replace data byte on $e000-$ffff when cartridge has its own RAM memory mapped at $6000-$7fff? * Genie must drive the slave cart's /ROMSEL with 1, otherwise its ROM won't be disabled. * Genie can't drive M2 with 0, otherwise its 4 kB PRG-ROM chip would be enabled * But then slave cart's logic sees this cycle as read from $6000-$7fff and thus its RAM will drive data bus so Genie swapping won't succeed.

Cart name		Notes for chip search: Use "+" as delimeter for all fields (except "cart name", where space is used); if many values are entered, all of them must appear in the cartridge then; case is not sensitive "Mapper" is the actual mapper used by this cartridge hardware (might not match the one at wiki.nesdev.com, as at the moment I was analyzing this cartridge, there was no mapper assigned to it, so I had to assign my own number for testing) "Original mapper" is the mapper used by licensed version of this game (for multicarts, it refers to mapper of the inside games, so 0+2 means this cartridge can run NROM+UNROM games) Order in which you put values doesn't matter (you can write 7400+74138+7400 or 7400+7400+74138 to search for a cartridge that contains at least two 7400 chips and one 74138 Some chips (like PAL168) appear in cartridges as 16V8 or 16L8, so be sure to check both posibilities Same goes for memories - type 27F080 to search for 32 pin memories, 27512 for 28 pin with two chip enables or MASKROM_1M_DIP28 for 28 pin with one chip enable Same goes for mappers - some examples: AX5904(MMC1), AX5202P(MMC3), PT8154BM (9112MMC3), AX5208C(VRC4), 23C3662(VRC2) Good news is that you can use wildcards, so 74139+MMC3* will search for any cartrige that has at least one 74139 and MMC3 chip in any version
Mapper#
Original mapper#
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