Namco System 21

Overview

The Namco System 21, also known as the "Polygonizer" or "Polygoniser", is an arcade system board. It was the first gaming system dedicated to polygonal 3D graphics, and was the most powerful gaming hardware of the 1980's. Its 3D graphical capabilities would not be surpassed until the release of Sega's Model 1 arcade system in 1992.

It debuted in 1988 with the game Winning Run. It was the first gaming system specifically designed for 3D polygon processing. It was in development for over three years before release, since around the mid-1980s. It was preceded by the Namco System 2 in 1987 and succeeded by the Namco System 22 in 1993.

System 21 games such as Galaxian³ and StarBlade established Namco as the market leader in polygonal 3D video games up until the arrival of the Sega Model 1 in 1992. According to Phil Harrison (in the September 1989 issue of Commodore User), who visited Namco's Tokyo office, Atari's Hard Drivin' ran on an earlier, less powerful, version of this hardware, stating that Namco and Atari Games were sister companies at the time and that the System 21 was a shared development.

Technical Specifications

The Namco System 21 consisted of four PCB's (printed circuit boards) in a metal casing and featured more graphics chips than any other gaming system up until then. Of the four boards, the main one was the CPU board, which featured a multi-core 16/32-bit CPU design. The four main CPU processors provided a combined performance of nearly 10 MIPS (Million Instructions Per Second).

The most important board, however, was the 3D graphics board, which contained multiple graphics chips dedicated to 3D graphics; this was the first dedicated 3D graphics board and a precursor to the 3D graphics accelerator cards that later appeared for the PC-98 and PC platforms. The core GPU (Graphics Processing Unit) processors of the 3D graphics board were five dedicated DSP (Digital Signal Processing) graphics processors, providing a combined performance of 63 MIPS dedicated to processing the complex 3D graphics for that time. In total, the four CPU and five DSP processors provided a combined performance of 73 MIPS, which was far beyond what other gaming systems were capable of in the 1980s.

It was also able to push 60,000 polygons per second, which was unrivalled by any other gaming systems up until the Sega Model 1 arcade board in 1992.

Main CPU (Central Processing Unit) board

• Main CPU processors: 2x Hitachi/Toshiba 68HC000 (16/32-bit Motorola 68000) @ 12.3 MHz
  • Performance: 4.4 MIPS (Million Instructions Per Second) (2.2 MIPS each)
• Additional CPU: Motorola 68020 (32-bit) @ 12.3 MHz / Motorola 68000 (16/32-bit) @ 12.3 MHz
  • Instruction performance: 4 MIPS (68020) / 2.2 MIPS (68000)
  • Floating-point (68020) performance: 100,000 FLOPS (Floating-point Operations Per Sec)
• Sound CPU: Motorola MC68B09EP (based on 8/16-bit Motorola 6809) @ 3.1 MHz
  • Performance: 1.3 MIPS
  • Physical memory: 64 KB
• MCU (Micro-Computer Unit) processor: Hitachi HD63705 (8-bit) @ 2.1 MHz
  • EPROM (Erasable Programmable Read-Only Memory) memory: 4 KB
• FM synth (Frequency Modulation synthesis) sound chip: Yamaha YM2151 (OPM) @ 3.6 MHz
  • DAC (Digital-to-Analog Converter) sound chip for FM synth: Yamaha YM3012 (stereo)
• PCM (Pulse-Code Modulation) sound chip: Namco C140 (24-channel, 21.4 KHz sampling rate)
  • DAC sound chip for PCM audio: Namco LC7880
• XTAL: 3.6 MHz
• OSC: 49.2 MHz
• ROM (Read-Only Memory) voice memory: 16 MB (4x 4 MB modules)
• RAM (Random Access Memory) chips: 2x MB8464, 2x MCM2018, 4x HM65256, 2x HM62256
• Custom chips: 2x Namco 148, Namco C68, Namco 139, Namco 137, Namco 149
• Other chips: Sharp PC900 & PC910 opto-oscillators, Hitachi HN58C65P (EEPROM), Fujitsu MB3771, 2x Fujitsu MB87077-SK, Sanyo LB1760, SYS87B-2B, CY7C132

3D graphics board

• GPU (Graphics Processing Unit) processors:
  • DSP (Digital Signal Processing) processors: 5x TI TMS320C20 (16/32-bit) @ 25 MHz
    • Performance: 62.5 MIPS (12.5 MIPS each)
  • Custom processors: 4x Namco 327, 4x Namco 342, 2x Namco 197, Namco 317 & 195
• OSC: 40 MHz
• Video RAM (VRAM) chips: 2x Hitachi HM62832, 4x Mitsubishi M5M5189, 16x ISSI IS61C68
• ROM (Read-Only Memory) chip: Texas Instruments TMS27C04
• Graphics display program ROM: GPR0L, GPR0U, GPR1L, GPR1U, GP0L, GP0U, GP1L, GP1U
• Graphics display data ROM: GDT0L, GDT0U, GDT1L, GDT1U, GD0L, GD0U, GD1L, GD1U
• Frame rate: 60 frames per second
• Geometric performance: 60,000 polygons per second (1000 polygons per frame)

Other specifications

• 2D graphics: Namco NB1 sprite system
• OSC for other two boards: 20 MHz and 38.8 MHz
• RAM chips for other two boards: 10x HM62256, 4x 84256, 5x CY7C128, 4x M5M5178
• Other custom Namco chips: C355, 187, 138, 165

• Other chips: 16x 157, 2x L7A0564, MB8422-90LP, L7A0565 316, 150, 167

References

• Namco System 21 Hardware, System 16
• System 21, Wiki Arcade Game Board