SNK NEO GEO system history/tech specs

 

SNK NEO GEO is a cartridge-based arcade and home video game system released in 1990.

The system offered comparatively colorful 2D graphics and high-quality sound, along with a memory card storage system usable on both versions of the system. A major platform for arcade games at the time, the system was also available as a high-end home gaming console. The two versions of the system were known as the AES (Advanced Entertainment System, the home version) and the MVS (Multi Video System, the arcade version). The Neo Geo was marketed as 24-bit, which may be a reference to either its 24-bit graphics data bus or its 8/16/32-bit multi-processing system.

The Neo Geo hardware was an evolution of an older SNK/Alpha Denshi M68000 arcade system board.

The MVS (Multi Video System) is the arcade form of the Neo Geo, and the operator could install multiple games on one cabinet, depending on the type of motherboard used. There are several single-slot motherboard variations (all of which are capable of playing one game at a time), along with a two-slot motherboard for playing two games, one that could run up to four games, and lastly, one which held up to six games. The AES (Advanced Entertainment System) is the home version of the Neo Geo hardware. Early motherboard revisions of the AES console contained daughterboards used to enhance the clarity of the video output.

The programming code is the same on both the MVS and AES hardware. In fact, owners could move EPROMs from one type to the other, and the game would still run. The program specifics for both MVS and AES game options were contained on every game ROM, whether the cartridge was 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.

MVS boards came in different sizes with different number of slots.

 4-slot MVS arcade cabinet

There are various MVS board types.

Cheapest way of getting into this system is to "consolize" MVS, meaning, take small MVS board from the arcade cabinet, such as top-loading 1 slot MV-1C, and connect it with supergun/cbox via jamma connection, That way you get db15 connection for controllers and power. Supergun/cbox also have video output such as composite or rgbs. Do your due diligence with this, since they come in various shapes, with various controller options, video outputs and are of different quality.

Another option is to buy already consolized package, everything pre-built from Aliexpress or Ebay.

Specification for ROM size was up to 330 megabits, hence the system displaying "MAX 330 MEGA - PRO GEAR SPEC" upon startup. While no technical specifications were required to display it, some games over 100 megabits followed this screen by displaying an animation proclaiming "The 100 Mega Shock". The original ROM size spec was later enhanced on cartridges with bank switching memory technology, increasing the maximum cartridge size to around 716 Mbit. These new cartridges also caused the system to display "GIGA POWER" upon startup, indicating this enhancement.



When I was a kid I was literally blown away when I first saw this arcade machine. Not even Street Fighter 2 CPS1 was a match when I first saw Samurai Shodown/Spirits 1 and 2. It was engraved in my memory and my life forever. After that I saw The King of Fighters '94, then Aero Fighters 2, Spinmaster, Metal Slug etc. It really was 2 light years ahead of anything you could've had at home, and back at home I had a famiclone. :D

Graphics

Unlike other video game consoles of its time, the Neo Geo did not use tilemap background layers. Instead, it relied exclusively on drawing sprites to create the background. Sprites are vertical strips which are 16 pixels wide, and can be 16 to 512 pixels tall. By laying multiple sprites side by side, the system can simulate a background layer. The system can draw up to 384 sprites on the screen at a time, and up to 96 per scanline.

Processor

Main Processor: Motorola 68000 running at 12 MHz

Although the MC68000 CPU was designed by Motorola, there were many other clones of this CPU found in the Neo Geo hardware. The most common CPU is the TMP68HC000 manufactured by Toshiba.

Co-Processor: Zilog Z80 running at 4 MHz. This is also used as an audio controller.

Sound chip: Yamaha YM2610 15 Sound Channels. 7 Digital, 4 FM synthesis, 3 PSG, and 1 Noise Channel.

Memory

Main Memory (used directly by 68K): 64KB

Main Video memory: 74KB

Video Memory: 64KB

Palette Memory: 8KB

Fast Video RAM: 2KB

Sound Memory (used directly by Z80): 2KB

Display

Display resolution: 320x224 (many games only used the centermost 304 pixels)

Color Palette: 65,536

Maximum Colors On-Screen: 4,096

Maximum Sprites On-Screen: 380

Minimum Sprite Size: 1x2

Maximum Sprite Size: 16x512

Maximum Sprites per scanline: 96

Background Layers: 0

Aspect ratio: 4:3

A/V output: RF, composite video, RGB (with separate 21 pin SCART cable FCG-9).

Sound

Sound CPU: Z80 at 4 MHz

Sound hardware: YM2610 at 8 MHz, stereo sounds up to 56 kHz

4 channels FM (4 operators + LFO)

3 PSG

1 noise

7 4-bit ADPCM

Work RAM (sound): 2KB

Sound ROM 128KB on-board (only less than 32KB used)

up to 512KB sound ROM on cartridges

Power

Source: separate DC 5V (older systems) and DC 9V adapter (newer systems).

Consumption: 8W older Systems, 5W newer Systems

AES console

AES console came bundled with this cool arcade stick controller.
AES console was super expensive at the day.
Initially, the home system was only available for rent to commercial establishments, such as hotel chains, bars and restaurants, and other venues. When customer response indicated that some gamers were willing to buy a US$650 console, SNK expanded sales and marketing into the home console market. The Neo Geo console was officially launched on 31 January 1990 in Osaka, Japan. The AES is identical to its arcade counterpart, the MVS, so arcade games released for the home market are nearly identical conversions. Super expensive to collect for. Better go with consolized MVS.

Neo Geo CD

The Neo Geo CD, released in 1994, was initially an upgrade from the original AES. This console uses CDs instead of ROM cartridges like the AES. The unit's (approximately) 1X CD-ROM drive was slow, making loading times very long with the system loading up to 56 Mbits of data between loads. Neo Geo CD game prices were low at US$50, in contrast to Neo Geo AES game cartridges which cost as much as US$300. The system could also play Audio CDs. Three models were released, the original top loader model, a revised front loader, and the CDZ, which featured a faster CD drive and was only released in Japan. All three versions of the system have no region-lock.

The Neo Geo CD was bundled with a control pad instead of a joystick like the AES. However, the original AES joystick can be used with all 3 Neo Geo CD models instead of the included control pads.

Neo Geo Pocket/Color

The Neo Geo Pocket was SNK's first handheld console in the Neo Geo family. Featuring a monochrome display, it was originally released in late 1998 exclusively in the Japan and Hong Kong markets. Lower than expected sales resulted in its discontinuation in 1999, whereupon it was immediately succeeded by the Neo Geo Pocket Color, which had a color screen. This time it was also released in the North American and European markets. About two million units were sold worldwide. The system was discontinued in 2000 in Europe and North America but continued to sell in Japan until October 30, 2001.