Editing Neo Geo (section)

=={{anchor | Technical aspects}}Technical specifications==
[[File:Neogeoguts.JPG|thumb|right|Inside a four cartridge Neo Geo arcade machine]]
[[File:Neo-Geo-AES-Opened-FL.jpg|thumb|right|Neo Geo AES [[motherboard]]]]
Each joystick controller is 280 mm (width) × 190 mm (depth) × 95 mm (height) (11 × 8 × 2.5 in.) and contains the same four-button layout as the arcade MVS [[Arcade cabinet|cabinet]].

The arcade machines have a [[memory card]] system by which a player could save a game to return to at a later time and could also be used to continue play on the SNK home console of the same name.<ref>{{cite magazine |title=This Fall Everything Turns To Gold With Neo-Geo: The Player's Gold Card Keeps Them Coming Back For More |magazine=RePlay |date=November 1990 |volume=16 |issue=2 |pages=26–7 |url=https://archive.org/details/re-play-volume-16-issue-no.-2-november-1990-600dpi/RePlay%20-%20Volume%2016%2C%20Issue%20No.%202%20-%20November%201990/page/26/mode/2up}}{{dead link|date=April 2025}}</ref>

The arcade version of the [[video game hardware]] is often referred to as the "MVS", or Multi Video System (available in 1-slot, 2-slot, 4-slot, and 6-slot variations, differing in the amount of game cartridges loaded into the machine at the time), with its console counterpart referred to as the "AES", or Advanced Entertainment System. Early motherboard revisions contain [[daughterboard]]s, used to enhance the clarity of the video output.

The MVS and AES hardware can execute identical machine code. Owners can move [[EPROM]]s from one type to the other, and the game will still run. The program specifics for both MVS and AES game options are contained on every game ROM, whether the cartridge is intended for home or arcade use. However, the arcade and home cartridges do have a different [[pinout]]. They were designed this way to prevent arcade operators from buying the cheaper home carts and then using them in arcades. In a few home version games,{{which|date=May 2021}} the arcade version of the game can be unlocked by inputting a special code.{{which|date=May 2021}}{{citation needed|date=May 2021}}

===ROM sizes and startup screens===
The original specification for ROM size is up to 330 [[megabits]], hence the system displaying "Max 330 Mega Pro-Gear Spec" upon startup. While no technical advances were required to achieve it, some games over 100 megabits, such as ''[[Top Hunter]]'', followed this screen by displaying an animation proclaiming "The 100Mega Shock!". The original ROM size specification was later enhanced on cartridges with [[bank switching]] memory technology, increasing the maximum cartridge size to around 716 megabits. These new cartridges also cause the system to display "Giga Power Pro-Gear Spec" upon startup or during [[attract mode]], indicating this enhancement.
<gallery>
File:neogeo_100megashock.png|The 100Mega Shock!
File:GigaPower.png|Giga Power
</gallery>

[[File:Neo-Geo-AES-Cartridge-Bottom.jpg|thumb|right|250px|The game cartridges measure {{cvt|19|cm}} by {{cvt|14|cm}} by {{cvt|2.5|cm}}.]]
[[File:Neo-Geo-Memory-Card.jpg|thumb|right|250px|Neo Geo [[Memory Card]]]]

The system uses seven different specialist [[Microprocessor|processors]], which divide the workload for the visuals, audio and gameplay.<ref>Elizabeth Olson, "Neo Geo: The Shape of Things to Come?", ''[[Game Informer]]'', issue 2 (November–December 1991), page 14</ref>

===Processors===
* [[Central processing unit|CPU]]: [[Motorola 68000]] (often a [[second source]]d version, usually by [[Toshiba]] or [[Hitachi]], initially a Hitachi HD68HC000PS12) @ 12 [[hertz|MHz]]<ref name="Specification"/> ([[16-bit#16/32-bit Motorola 68000 and Intel 386SX|16/32-bit]] [[Instruction set|instructions]] @ 1.75 [[Instructions per second|MIPS]]<ref name=retro>{{cite web|url=https://drolez.com/retro/|title=Lud's RetroComputing Info|website=drolez.com}}</ref>)
* [[Coprocessor]]: [[Zilog Z80]] @ 4&nbsp;MHz (also used as audio controller) ([[8-bit|8]]/16-bit instructions @ 0.58 MIPS<ref name=retro/>)

===Memory===
[[Random-access memory|RAM]]: 214 [[Kibibyte|KB]] [[Static random-access memory|SRAM]]<ref name=mvstech/><ref name="Specification"/>
* Main 68000 [[Random-access memory|RAM]]: 64 KB (32 KB SRAM ×2)
* [[Video memory|Video RAM]]: 84 KB SRAM
** Main [[VRAM]]: 64 KB (32 KB SRAM ×2)
** Palette memory: 16 KB (8 KB SRAM ×2)
** Fast video [[Texture memory|sprite RAM]]: 4 KB (2 KB SRAM ×2)
* Z80 sound RAM: 2 KB SRAM
* Battery-backup [[Saved game|save]] [[Non-volatile random-access memory|NVRAM]]: 64 KB SRAM

On-board [[Read-only memory|ROM]]: 512 KB<ref name=mvstech/>
*Zoom [[Lookup table|look-up table]]: 128 KB
*Fix layer graphics: 128 KB
*Z80 sound: 128 KB
*68000 [[BIOS]]: 128 KB

===Display===
[[File:Snk lspc2-a2 mcmaster mz ns20x.jpg|thumb|The die of the SNK LSPC2-A2]]
The SNK custom video chipset allows the system to draw [[Sprite (computer graphics)|sprites]] in vertical strips of tiles (blocks of 16x16 pixels), and can be 32 tiles tall (total of 512 pixels); it can draw up to 380 sprites on the screen at a time, with the limitation of 96 sprites per scanline. Each tile can be assigned a palette, which defines 15 colors (+ transparency). Allowing up to 256 palettes at the same time, the system can display 3840 colors simultaneously. Unlike most other video game consoles of its time, the Neo Geo does not use scrolling [[Tile engine|tilemap]] background layers. Instead, it has a single non-scrolling tilemap layer called the fix layer, while any scrolling layers rely exclusively on drawing sprites to create the scrolling backgrounds (like the [[Sega Y Board]]). By laying multiple sprites side by side, the system can simulate a tilemap background layer. The Neo Geo sprite system represents a step between conventional sprites and tilemaps.<ref name=mvstech>{{cite web|first=Charles |last=MacDonald |url=http://furrtek.free.fr/noclass/neogeo/mvstech.txt |title=Neo*Geo MVS Hardware Notes |access-date=2012-01-26}}</ref>

* [[Graphics processing unit|GPU]] chipset:<ref>{{Cite web |url=https://wiki.neogeodev.org/index.php?title=GPU |title=GPU - NeoGeo Development Wiki |access-date=2014-09-26 |archive-url=https://web.archive.org/web/20151210234154/https://wiki.neogeodev.org/index.php?title=GPU |archive-date=2015-12-10 |url-status=dead }}</ref>
** [[SNK]] LSPC2-A2 (line sprite generator & VRAM interface) @ 24&nbsp;MHz<ref name=mvstech/>
** SNK PRO-B0 (palette arbiter)<ref>{{cite web|url=https://wiki.neogeodev.org/index.php?title=Category:Chips|title=Category:Chips - NeoGeo Development Wiki|website=wiki.neogeodev.org}}</ref>
** SNK PRO-A0, NEO-B1, NEO-GRC<ref>{{cite web|url=http://consolegen.weebly.com/snk-neo-geo-aes.html|title=SNK Neo Geo AES|website=ConsoleGen}}</ref>
* GPU graphics data [[Bus (computing)|bus]]: [[24-bit computing|24-bit]]<ref>[https://wiki.neogeodev.org/index.php?title=P_bus P bus], Neo Geo Development</ref><ref>[https://wiki.neogeodev.org/index.php?title=LSPC2-A2 LSPC2-A2], Neo Geo Development</ref>
* [[Display resolution]]: 320×224 [[Pixel|px]] (many games only use the centermost 304 px),<ref name=mvstech/> [[progressive scan]]
* [[Palette (computing)|Color palette]]: 65,536 ([[Highcolor|16-bit]]) (not RGB565, but RGB666, where the lowest bit of each channel is shared, being common to the three RGB components)<ref name=mvstech/>
* Maximum colors on screen: 3840
* Maximum [[Sprite (computer graphics)|sprites]] on screen: 380<ref name="Specification"/>
* Minimum sprite size: 16×16 px<ref name="Specification"/>
* Maximum sprite size: 16×512 px<ref name="Specification"/>
* Maximum sprites per [[Scan line|scanline]]: 96<ref name="Specification"/>
* Maximum [[Texel (graphics)|sprite pixels]] per scanline: 1536 px<ref name=mvstech/>
* Static [[Tile engine|tilemap]] plane: 1 (512×256 px fix layer)<ref name=mvstech/>
* Aspect ratio: 4:3
* A/V output: RF, [[composite video]]/RCA audio, [[RGB]] (with separate 21 pin RGB cable FCG-9, or European standard RGB SCART cable).

===Sound===
The onboard [[Yamaha YM2610]] [[sound chip]] provides 14 channels of sound.

* [[Sound chip]]: [[Yamaha YM2610]]<ref name="Specification"/>
* 4 concurrent [[FM synthesis]] channels (voices), four operators per channel
* 3 [[Programmable sound generator|SSG]] channels
* 7 [[pulse-code modulation]] (PCM) channels<ref name="ACME"/>
** ADPCM-A: 6 [[Adaptive DPCM|ADPCM]] channels, 18.5&nbsp;kHz [[Sampling (signal processing)|sampling]] rate, 12-bit [[Audio bit depth|audio depth]]<ref name=ym2610>{{cite web|url=https://wiki.neogeodev.org/index.php?title=YM2610|title=YM2610 - NeoGeo Development Wiki|website=wiki.neogeodev.org}}</ref>
** ADPCM-B: 1 ADPCM channel,  1.85–55.5&nbsp;kHz sampling rate, 16-bit audio depth<ref name=ym2610/>
* 2 [[Programmable Interval Timer|interval timers]]
* 1 [[Low frequency oscillation|low frequency oscillator]] (LFO)
* Sound/Work RAM: 2 KB<ref name="Specification"/>
* Sound ROM: 128 KB on-board (only less than 32 KB used), up to 512 KB sound ROM on cartridges

===Other===
;Power
* Source: separate DC 5 [[Volt|V]] (older systems) and DC 9 [[Volt|V]] adapter (newer systems).
* Consumption: 8 [[Watt|W]] older systems, 5 [[Watt|W]] newer systems

;Dimensions
* Console: 325&nbsp;mm (width) × 237&nbsp;mm (depth) × 60&nbsp;mm (height)
* Controller: 280&nbsp;mm (width) × 190&nbsp;mm (depth) × 95&nbsp;mm (height)

;Console storage

* Removable memory card: 2 KB or 68-pin [[JEIDA memory card|JEIDA]] ver. 3 spec memory.<ref>Neo-Geo Hardware Specification <!-- https://archive.org/details/NeoGeoHardwareSpecification --></ref>  Any 68-pin memory that fits the JEIDA version 3 spec will work.

;Arcade storage

* Removable memory card: 68-pin.  Cartridge is composed of two PCBs.<ref>{{cite web|url=http://forums.arcade-museum.com/showthread.php?t=65639|title=Repairing a Neo-Geo MVS cartridge?|access-date=2011-12-14|date=June 2007}}</ref>