The Atomiswave system

Atomiswave was Sammy's arcade board, released in 2003. Inside it's very close to a Sega Dreamcast, with games on cartridges instead of discs.

The board

The main board is the Sammy AM3AGA-04, dated 2002. Sega later made a revision, 837-14624R, with updated versions of the same chips. MAME's developers sum it up as "basically just a Sega Dreamcast using ROM carts".

Part	What it is
CPU	Hitachi SH-4 (HD6417091RA), as in the Dreamcast
Graphics and system	Sega 315-6267, the Dreamcast's graphics and system chip
Sound	Sega 315-6232, the Dreamcast's sound chip
Other custom chips	Sega 315-6258, and Sammy's "ROMEO" gate arrays (AX0201A01)
Main memory	Two 64-Mbit SDRAMs (NEC µPD4564323), 16 MB in total
Graphics and sound memory	Five 16-Mbit SDRAMs (NEC µPD4516161)
BIOS	1-Mbit flash ROM (Macronix 29L001MC); 4-Mbit on Sega's revision
Settings and bookkeeping	128 KB of battery-backed SRAM
Audio out	Burr-Brown PCM1725U DAC and a Toshiba 19 W × 2 amplifier
Video out	JAMMA, plus a 15-pin VGA connector at 31.5 kHz

Under the board are connectors for the game cartridge, a communication module, extra controls, a fan and a small serial daughterboard. The JAMMA edge connector carries the usual two-player controls and coins; a separate I/O board adds coin inputs for players 3 and 4.

Controls

Most games use ordinary joystick-and-button panels. The board can also be told that a port has a Dreamcast-style light gun, mouse or trackball attached, which is how the shooting and trackball games work. Light-gun games use a small gun sub-board (AM3AGT-02) with trigger, sensor and pump connectors for two players.

Cabinets

Atomiswave boards went into ordinary JAMMA cabinets and into Sammy's own designs:

The Atomiswave SD cabinet, built by Taito for Sammy: 750 × 903 × 1,765 mm, 110 kg, 140 W. It has a card slot built in.
The Net Select touchscreen cabinet, used for Salaryman Kintaro and Victory Furlong.

Sammy also made an AW Multiplayer System, which linked four JAMMA cabinets with a dedicated harness for local multiplayer. That link stayed inside one arcade and has nothing to do with AW-NET.

The service menu

The system menu has a Network Settings page. Switching NETWORK from OFF to ON makes the cabinet try to connect while it's showing its attract loop, and it retries after an error. The manual notes that the setting does nothing for a game without network support. The bookkeeping screen also has four NETWORK START counters for tournament play.

When it came out

Sammy first showed Atomiswave at the 2002 AM Show. Sammy's 2004 business report gives April 2003 as the release; trade-press chronologies put the hardware rollout in late June 2003. AW-NET came six months later, in December 2003.