Difference between revisions of "MBC5"

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{{Pandocs|memorybankcontrollers}}
 
==Overview==
 
==Overview==
 
MBC5 (Memory Bank Controller 5) is the 4th generation MBC. There apparently was no MBC4, presumably because of the superstition about the number 4 in Japanese culture. It is the first MBC that is guranteed to work properly with [[CGB-001|GBC]] [[CGB_Registers#FF4D_-_KEY1_-_CGB_Mode_Only_-_Prepare_Speed_Switch|double speed mode]]. It can map up to 64 Mbits (8 MBytes) of ROM.
 
MBC5 (Memory Bank Controller 5) is the 4th generation MBC. There apparently was no MBC4, presumably because of the superstition about the number 4 in Japanese culture. It is the first MBC that is guranteed to work properly with [[CGB-001|GBC]] [[CGB_Registers#FF4D_-_KEY1_-_CGB_Mode_Only_-_Prepare_Speed_Switch|double speed mode]]. It can map up to 64 Mbits (8 MBytes) of ROM.

Revision as of 08:18, 25 May 2012

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Overview

MBC5 (Memory Bank Controller 5) is the 4th generation MBC. There apparently was no MBC4, presumably because of the superstition about the number 4 in Japanese culture. It is the first MBC that is guranteed to work properly with GBC double speed mode. It can map up to 64 Mbits (8 MBytes) of ROM.

0000-3FFF - ROM Bank 00 (Read Only)

Same as for MBC1.

4000-7FFF - ROM Bank 00-1FF (Read Only)

Same as for MBC1, except that accessing up to bank 1E0h is supported now. Also, bank 0 is actually bank 0.

A000-BFFF - RAM Bank 00-0F, if any (Read/Write)

Same as for MBC1, except RAM sizes are 64kbit, 256kbit and 1mbit.

0000-1FFF - RAM Enable (Write Only)

Mostly the same as for MBC1, a value of 0Ah will enable reading and writing to external RAM. A value of 00h will disable it.

2000-2FFF - Low 8 bits of ROM Bank Number (Write Only)

The lower 8 bits of the ROM bank number goes here. Writing 0 will indeed give bank 0 on MBC5, unlike other MBCs.

3000-3FFF - High bit of ROM Bank Number (Write Only)

The 9th bit of the ROM bank number goes here.

4000-5FFF - RAM Bank Number (Write Only)

As for the MBC1s RAM Banking Mode, writing a value in range for 00h-0Fh maps the corresponding external RAM Bank (if any) into memory at A000-BFFF.

Schematic

MBC5.png

Source: [1]