From Wikipedia, the free encyclopedia Memory Management Controller
Memory Management Controller
Multi-Memory Controllers or Memory Management Con- The MMC2 is only used in Mike Tyson’s Punch-Out!! and
trollers[1] (MMC are different kinds of special chips de-
MMC) the later rerelease which removed Mike Tyson. A single
signed by various video game developers for use in Nin- 8KB bank of program ROM could be selected (with the
tendo Entertainment System (NES) cartridges. These remaining 24KB locked) and character ROM could be se-
chips extended the capabilities of the original console lected in two pairs of 4KB banks, which would be auto-
and made it possible to create NES games with features matically switched when the video hardware attempted
the original console could not offer. to load particular graphic tiles from memory, thus allow-
With the advent of NES emulators, the code written ing a larger amount of graphics to be used on the screen
to emulate these chips became known as mappers. without the need for the game itself to manually switch
them.[4]
List of MMC chips MMC3
UNROM
• Manufacturer: Nintendo
• Games used in: Pro Wrestling (Nintendo Entertainment
System),[1]:29 Ikari Warriors, Mega Man, Contra (video
game)
Early NES mappers were made of 7400 series discrete log-
ic chips.[1]:29 The UNROM, implemented with two such
chips, divided the program space into two 16 KiB banks.
The mapper allowed a program to switch one bank while
keeping one bank always available. [2] Instead of a dedi-
cated ROM chip to hold graphics data (called CHR by Nin-
tendo), games using UNROM stored graphics data on the
program ROM and copied it to a RAM on the cartridge at
run time.[1]:29
The MMC3 chip, soldered onto a PCB containing Super Mario
MMC1 Bros. 3 and others.
• Manufacturer: Nintendo
• Games used in: The Legend of Zelda, Metroid et al. • Manufacturer: Nintendo
The MMC1 was Nintendo’s first custom mapper integrat- • Games used in: Super Mario Bros 2, Super Mario Bros. 3
ed circuit to incorporate support for saved games and et al.
multi-directional scrolling configurations.[1]:30 The chip The MMC3 was Nintendo’s most popular MMC chip. It
comes in at least five different versions: MMC1A, MMC1B1, comes in MMC3A, B, and C revisions. The MMC3 added a
MMC1B2, MMC1B3 and MMC1C. The differences between scanline based IRQ counter to make split screen scrolling
the different versions are slight, mostly owing to saveg- easier to perform (mainly to allow the playfield to scroll
ame memory protection behavior. The MMC1 chip al- while the status bar would remain motionless at the top
lowed for switching of different memory banks. Program or bottom of the screen), along with two selectable 8KB
ROM could be selected in 16KB or 32KB chunks, and char- program ROM banks and two 2KB+four 1KB selectable
acter ROM could be selected in 4KB or 8KB chunks. An un- character ROM banks.[5]
usual feature of this memory controller was that its in-
put was serial, rather than parallel, so 5 sequential writes MMC4
(with bit shifting) were needed to send a command to the • Manufacturer: Nintendo
circuit.[3] • Games used in: Fire Emblem, Fire Emblem Gaiden, and
Famicom Wars
MMC2 This chip is only used in three games, all of which were
• Manufacturer: Nintendo released only for the Famicom in Japan, and were de-
• Games used in: Mike Tyson’s Punch-Out!! veloped by Intelligent Systems. Functionally, it is nearly
1
From Wikipedia, the free encyclopedia Memory Management Controller
identical to the MMC2, where the only difference is that The A*ROM mapper, named after the AMROM, ANROM,
the MMC4 switches program ROM in 16KB banks instead and AOROM cartridge boards that use it, was developed
of 8KB banks and has support for a battery-backed SRAM by Chris Stamper of Rare Ltd., and manufactured by Nin-
to save game data.[6] tendo. It is found in games developed by Rare for Ninten-
do, Tradewest, GameTek, Acclaim, and Milton Bradley.[9]
MMC5 It uses 32 KB ROM switch and a CHR RAM. Unlike other
• Manufacturer: Nintendo chips, it uses one screen mirroring.[10]
• Games used in:
Castlevania III: Dracula’s Curse(NA/EU), Just Breed, Metal Third-party chips
Slader Glory, Laser Invasion, Uchuu Keibitai SDF,
Nobunaga’s Ambition II, Nobunaga no Yabou - Sengoku As only first-party hardware was allowed in North Amer-
Gunyuu Den, Bandit Kings of Ancient China, Romance of ica and Europe, these third party chips were supposed to
the Three Kingdoms II, Uncharted Waters, Aoki Ookami be used only in Japan. However, recently some of them
to Shiroki Mejika - Genchou Hishi, Gemfire, L’Empereur, had been found in a few North American cartridges as
Ishin no Arashi, Shin 4 Nin Uchi Mahjong - Yakuman Ten- well.
goku
The MMC5 was Nintendo’s largest mapper. It was also VRC2
the most expensive, making developers avoid it. Only • Manufacturer: Konami
Koei seemed to use this chip regularly in their games • Games used in: Contra (Japan), Tiny Toon
once it was released. The chip has 1 KB of extra RAM, Adventures (Japan), Akumajō Special: Boku Dracula-
extra sound channels (two square waves), supports verti- kun
cal split screen scrolling, improved graphics capabilities The VRC2 is a chip from Konami that allows program
(making 16,384 different tiles available per screen rather ROM to be switched in 8KB banks, and character ROM to
than only 256, and allowing each individual 8x8-pixel be switched in 1KB banks. This mapper had two known
background tile to have its own color assignment instead revisions: VRC2a and VRC2b. [11]
of being restricted to one color set per 2x2 tile group),
highly configurable program ROM and character ROM VRC4
bank switching, and a scanline-based IRQ counter.[7]
MMC6
• Manufacturer: Nintendo
• Games used in: StarTropics, Zoda’s Revenge: StarTropics
II
The MMC6 is similar to the MMC3, with an additional 1
KB of RAM which can be saved with battery backup.[8]
Famicom Disk System
• Manufacturer: Nintendo
• Games used in: Arumana no Kiseki, Ai Senshi Nicol, Bio
Miracle Bokutte Upa, Exciting Basket, Falsion, Meikyuu Jiin
Dababa, Nazo No Kabe, Risa no Yousei Densetsu, Relics -
Ankoku Yousai, Big Challenge! Dogfight Spirit, Famicom
Tantei Club Part II, Link no Bouken, Metroid (Japanese
Version), Nazo no Murasame Jō, Palthena no Kagami (FDS
version of Kid Icarus), Pro Wrestling, Shin Onigashima,
Vs. Excitebike FDS, Yuuyuuki, Zelda no Densetsu,
KikiKaiKai, etc.
The Famicom Disk System’s ASIC was an extended chip, The VRC4.
which supports additional sound channels.
• Manufacturer: Konami
AOROM
VRC6
• Manufacturer: Nintendo
• Games used in: Battletoads, Wizards & Warriors, • Manufacturer: Konami
Cobra Triangle, Jeopardy! • Games used in: Akumajou Densetsu, Madara, Esper
Dream II
2
From Wikipedia, the free encyclopedia Memory Management Controller
All of these games were only released in Japan.
NAMCO106 was an advanced chip using 4-bit sample
table synthesis, that supports up to 8 extra sound chan-
nels, with aliasing increasing with the number of active
channels.
FME-7
• Manufacturer: Sunsoft
• Games used in: Batman: Return of the Joker, Hebereke,
Gimmick!, et al.
The VRC6.
The FME-7 was a memory mapping circuit developed by
Sunsoft for use in NES and Famicom cartridges. It allows
The VRC6 (Virtual Rom Controller) was an advanced the program ROM to be switched in 8KB banks and the
MMC chip from Konami, supporting bank switching for character ROM to be switched in 1KB banks. It also con-
both program code and graphics as well as a scanline- tains hardware allowing the cartridge to generate IRQ
based IRQ counter. The chip also contained support for signals after a specified number of CPU clock cycles, thus
3 extra sound channels (two square waves and one saw- enabling split-screen effects with minimal use of process-
tooth wave). It was used in Akumajou Densetsu (the Ja- ing power. A special version of this mapper, labeled as
panese version of Castlevania III: Dracula’s Curse), while the "SUNSOFT 5" rather than "FME-7", contains sound gen-
western version used the MMC5 from Nintendo. Since eration hardware which appears to be a subset of the
the NES, unlike the Famicom, did not allow cartridges well-known General Instrument AY-3-8910 (3 square
to add additional sound channels, the soundtrack on the waves). This sound generation hardware was used on on-
western versions could only access the original five ly one Famicom title – Gimmick!
sound channels built into the NES and had to be re-
worked.
Unlicensed/Homebrew MMCs
VRC7 Some individual and unlicensed developers made custom
mappers for the NES, most of which simply expanded the
available memory.
228
• Manufacturer: Active Enterprises
• Games used in: Action 52, Cheetahmen II
228 was a simple bank switching mapper developed for
use in the notoriously poor-quality games Action 52 and
The VRC7 with a post-processor for the FM synthesis.
Cheetahmen II. It does not have a nametable control bit.
In the Action 52 multicart, it also contains a small 16-bit
• Manufacturer: Konami
register area that contains the old menu selection when
• Games used in: Lagrange Point
exiting a game.
The VRC7 was a very advanced MMC chip from Konami,
not only supporting bank switching and IRQ counting
equivalent to the VRC6 but also containing a YM2413 de- External links
rivative providing 6 channels of FM Synthesis audio. This
• Comprehensive NES Mapper Document v0.80 by
advanced audio was used only in the Famicom game La-
\Firebug\
grange Point; while the Japanese version of Tiny Toon Ad-
• Bigass NES Mapper List 0.1
ventures 2 also used the VRC7, it did not make use of the
extended audio.[12]
References
NAMCO106 [1] ^ "Why Game Paks Never Forget" from Nintendo
• Manufacturer: Namco Power #20 Mar/Apr 1991, pp. 28-31.
• Games used in: Erika to Satoru no Yumebouken, Final [2] UxROM from NESdevWiki Retrieved on 2009-11-21.
Lap, King of Kings, Mappy Kids, Megami Tensei II, Namco [3] MMC1 from NESdevWiki Retrieved on 2009-11-21.
Classic II, Sangokushi 2, Youkai Douchuuki, Rolling [4] Nintendo MMC2 from NESdevWiki
Thunder(JP) [5] Nintendo MMC3 from NESdevWiki
[6] Nintendo MMC4 from NESdevWiki
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From Wikipedia, the free encyclopedia Memory Management Controller
[7] Nintendo MMC5 from NESdevWiki [10] AOROM - NESdevWiki
[8] Nintendo MMC6 from NESdevWiki [11] Konami VRC2 from NESdevWiki
[9] List of NES games with publisher and board [12] Konami VRC7 from NESdevWiki
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Categories:
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