- For MBC1, MBC2, MBC3, MBC7: - `def rROMB equ $2000` (only MBC5 needs `rROMB0`+`rROMB1`) - For MBC1: - `def rBMODE equ $6000` ([banking mode select](https://gbdev.io/pandocs/MBC1.html#60007fff--banking-mode-select-write-only)) - For MBC6: - `def rRAMBA equ $0400` ([RAM bank A number](https://gbdev.io/pandocs/MBC6.html#0400-07ff--ram-bank-a-number-write-only)) - `def rRAMBB equ $0800` ([RAM bank B number](https://gbdev.io/pandocs/MBC6.html#0800-0bff--ram-bank-b-number-write-only)) - `def rFLASH equ $0C00` ([flash enable](https://gbdev.io/pandocs/MBC6.html#0c00-0fff--flash-enable-write-only)) - `def rFMODE equ $1000` ([flash write enable](https://gbdev.io/pandocs/MBC6.html#1000--flash-write-enable-write-only)) - `def rROMBA equ $2000` ([ROM/flash bank A number](https://gbdev.io/pandocs/MBC6.html#2000-27ff--romflash-bank-a-number-write-only)) - `def rFLASHA equ $2800` ([ROM/flash bank A select](https://gbdev.io/pandocs/MBC6.html#2800-2fff--romflash-bank-a-select-write-only)) - `def rROMBB equ $3000` ([ROM/flash bank B number](https://gbdev.io/pandocs/MBC6.html#3000-37ff--romflash-bank-b-number-write-only)) - `def rFLASHB equ $3800` ([ROM/flash bank B select](https://gbdev.io/pandocs/MBC6.html#3800-3fff--romflash-bank-b-select-write-only)) - For MBC7: - `def rRAMG1 equ $0000` ([RAM enable 1](https://gbdev.io/pandocs/MBC7.html#0000-1fff---ram-enable-1-write-only)) - `def rRAMG2 equ $4000` ([RAM enable 2](https://gbdev.io/pandocs/MBC7.html#4000-5fff---ram-enable-2-write-only)) - `def rRAMREG equ $A000` ([RAM registers](https://gbdev.io/pandocs/MBC7.html#a000-afff---ram-registers-readwrite), similar to MBC3 `rRTCREG`)
def rROMB equ $2000(only MBC5 needsrROMB0+rROMB1)def rBMODE equ $6000(banking mode select)def rRAMBA equ $0400(RAM bank A number)def rRAMBB equ $0800(RAM bank B number)def rFLASH equ $0C00(flash enable)def rFMODE equ $1000(flash write enable)def rROMBA equ $2000(ROM/flash bank A number)def rFLASHA equ $2800(ROM/flash bank A select)def rROMBB equ $3000(ROM/flash bank B number)def rFLASHB equ $3800(ROM/flash bank B select)def rRAMG1 equ $0000(RAM enable 1)def rRAMG2 equ $4000(RAM enable 2)def rRAMREG equ $A000(RAM registers, similar to MBC3rRTCREG)