Cartridge Types - Nintendo DMG-01 - Game Boy Console Manual

TM
Game Boy CPU Manual
Locations
014D Complement check
(PROGRAM WON'T RUN ON GB IF NOT CORRECT!!!)
(It will run on Super GB, however,
if incorrect.)
014E-014F Checksum (higher byte first) produced by
adding all bytes of a cartridge except for
two checksum bytes and taking two lower
bytes of the result. (GameBoy ignores this
value.)

2.6. Cartridge Types

The following define the byte at cart location 0147:
ROM ONLY
•
This is a 32kB (256kb) ROM and occupies 0000-7FFF.
MBC1 (Memory Bank Controller 1)
•
MBC1 has two different maximum memory modes:
16Mbit ROM/8KByte RAM
The MBC1 defaults to 16Mbit ROM/8KByte RAM mode
on power up. Writing a value (XXXXXXXS - X = Don't
care, S = Memory model select) into 6000-7FFF area
will select the memory model to use. S = 0 selects
16/8 mode. S = 1 selects 4/32 mode.
Writing a value (XXXBBBBB - X = Don't cares, B =
bank select bits) into 2000-3FFF area will select
an appropriate ROM bank at 4000-7FFF. Values of 0
and 1 do the same thing and point to ROM bank 1.
by DP
2.5.4. Reserved Memory
or 4Mbit ROM/32KByte RAM.
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