Namco System 22 / Super System 22¶
The first arcade board with texture mapping (Namco, 1993) — the Ridge Racer revolution. Gouraud, transparency, depth cueing, anti-aliasing, 240,000+ textured quads/s thanks to the Evans & Sutherland TR3 chipset. The Super System 22 (1995) pushes the polygon rate and effects further. A direct rival to the Sega Model 2.
PCB Namco System 22 — photo by Yaca2671, CC BY-SA 3.0 (Wikimedia Commons).
Identification¶
| Field | Value |
|---|---|
| Manufacturer | Namco |
| Years | System 22 (1993) · Super System 22 (1995) |
| Type | textured 3D (multi-board crate) |
| Cabinets | often cockpit / motion (Ridge Racer, Alpine Racer) |
Architecture¶
| Block | Chip | Clock | Role |
|---|---|---|---|
| CPU | Motorola 68EC020 | 24.576 MHz | game logic |
| DSP ×2 | TI TMS320C25 | 49.152 MHz | 3D geometry |
| GPU | Evans & Sutherland "TR3" | texture mapping + Gouraud + transparency + depth cueing + anti-aliasing | |
| Sound | Namco C352 | 32 voices PCM @ 42 kHz |
The E&S TR3 (from professional flight simulators) brings real-time texture
mapping — hence Ridge Racer's smooth, realistic look versus the bare polygons of the
System 21. Performance: > 240,000 textured quads/s. Emulated in
MAME (namco/namcos22.cpp).
Super System 22 (1995)¶
Same base, higher polygon rate and more effects — for heavier games (Time Crisis, Alpine Racer, Prop Cycle, Aqua Jet).
Notable games¶
Ridge Racer (1993), Ridge Racer 2, Ace Driver, Cyber Cycles, Rave Racer, Victory Lap, Cyber Commando … and on Super 22: Time Crisis (1995), Alpine Racer (1/2), Prop Cycle, Aqua Jet, Tokyo Wars, Dirt Dash, Alpine Surfer.
Common faults¶
| Symptom | Likely cause | Lead |
|---|---|---|
| No 3D / corrupt textures | TR3 GPU / DSP / texture RAM | Board-by-board crate diagnosis |
| Random freeze | 68EC020 / DSP / shared RAM | CPU diagnosis, RAM test |
| No/partial sound | C352 | Sound-stage diagnosis |
| Cabinet motion dead | motion board / actuators | Mechanical diagnosis |
| No image | Power, interconnects | Base diagnosis |
A multi-board crate + rare TR3 GPU → methodical diagnosis, irreplaceable customs. A 31 kHz monitor is common.
Modernisation & mods¶
The common ground for every JAMMA board
Video, power, control panel and upscalers depend on the cabinet rather than the board: everything is centralised in Modernising a cabinet. To run the board outside a cabinet (at home, on a display): supergun.
- Storage 🟡: the game lives in EPROM/mask ROM on the board. Changing or restoring a game means reprogramming the EPROMs (and, for a mask ROM, using a pinout adapter) → EPROM method.
- Media preservation: replacing the original storage, multicarts, ODEs and modern options by family → PCB preservation hub.
- Scan rate 📺: ~31.45 kHz / 59.9 Hz — high resolution (VGA class), ⚠️ a 31 kHz / tri-sync monitor is required; a 15 kHz chassis is incompatible → tri-sync and upscalers.
(Computed from the MAME sources —
namco/namcos22.cpp— pixel clock ÷ htotal.) - FPGA / emulation: see the Emulation & FPGA section below.
Repair (technician)¶
- C74/C76 MCU protection: a boot crash = the MCU (donor / MAME). The 3D data/textures are in mask ROM → no EPROM to reburn for that data.
- 3D customs: corrupt 3D = RAM + buffers first, the custom last (donor).
- Sound: C352 (32 voices @ 42 kHz) — diagnose the sound stage.
- Capacitors: recap. Program EPROM sockets (27C040/080): turned-pin socket.
→ Methods: PCB fault-finding · Recap · EPROM · Traces & vias
Expected clocks — measurement table ✅¶
Values extracted from the MAME sources for this platform. On a scope or frequency counter, a clock that is missing or off-value points straight at the crystal, the divider or the chip at fault — the fastest starting point on a dead board.
| Component | Expected clock | Role |
|---|---|---|
| M68020 | 24.576 MHz | main CPU |
How to read this table
Several values for one component = several board variants in this family (or several instances of the chip clocked differently). These frequencies are those of the clock signal at the component's input, not of its original crystal — on many boards the clock is divided down from a single master crystal.
DIP settings ✅¶
10 games on this platform, settings extracted from the MAME sources (INPUT_PORTS_START blocks). The Position column gives the switch's physical reference on the board (SW2:!3,!4 = bank SW2, levers 3 and 4) — which is what lets you set it up without the paper manual. Games are sorted by MAME set name.
DIP settings — MAME set acedrive
| Setting | Position | Options (default in bold) |
|---|---|---|
| Test Mode? | SW3:7 | Off · On |
| Test Mode? | SW3:8 | Off · On |
DIP settings — MAME set adillor
| Setting | Position | Options (default in bold) |
|---|---|---|
| Test Mode | SW4:1 | Off · On |
DIP settings — MAME set aquajet
| Setting | Position | Options (default in bold) |
|---|---|---|
| Test Mode | SW4:1 | Off · On |
DIP settings — MAME set cybrcycc
| Setting | Position | Options (default in bold) |
|---|---|---|
| Test Mode | SW4:1 | Off · On |
DIP settings — MAME set ridgera
| Setting | Position | Options (default in bold) |
|---|---|---|
| Test Mode | SW2:1 | Off · On |
DIP settings — MAME set ridgera2
| Setting | Position | Options (default in bold) |
|---|---|---|
| Test Mode 2 | SW3:8 | Off · On |
DIP settings — MAME set ridgerac3m
| Setting | Position | Options (default in bold) |
|---|---|---|
| PCB (screen) Select | SW2:1,2 | Center/Main (PCB 2) · Center/Main (PCB 2) · Left (PCB 1) · Right (PCB 3) |
DIP settings — MAME set ridgeracf
| Setting | Position | Options (default in bold) |
|---|---|---|
| Test Mode 2 | SW3:8 | Off · On |
DIP settings — MAME set timecris
| Setting | Position | Options (default in bold) |
|---|---|---|
| Test Mode | SW4:8 | Off · On |
DIP settings — MAME set tokyowar
| Setting | Position | Options (default in bold) |
|---|---|---|
| Test Mode | SW4:1 | Off · On |
Check against your own board
These settings apply to the game and revision described by MAME. One title may have several DIP sets depending on region or revision, and some systems use soft-dips (settings in memory, via the test menu) rather than physical switches. In case of a discrepancy, the board's silkscreen and the test menu are authoritative.
See also: DIP reference · game manuals
Procedure — a dead board, step by step ✅¶
What this adds
The general method lives in PCB diagnosis. This is its application to this platform: the same order, but with the values actually expected here, so you do not have to go back and forth.
Tools: multimeter, oscilloscope (or frequency counter), current-limited bench supply, desoldering braid. → Tooling
If the board is still in a cabinet
A CRT holds its charge with the machine unplugged. → CRT safety
1. Inspection, power off. Corrosion, cut tracks, oxidised EPROM legs, leaking SMD capacitors, dubious earlier repairs.
2. The connector, before anything else. A large share of "dead boards" are a contact problem, not a fault. Clean the contacts with isopropyl alcohol and reseat — not with an abrasive eraser on a gold edge, which takes the plating off and brings the problem back worse. It costs two minutes and settles the question.
3. Power, measured on the board. Aim for +5.0 V measured as close as possible to where power reaches the board — not at the PSU output: the drop is in the loom, and that is exactly what makes a board boot on the bench and not in the cabinet. Where you probe depends on this board's connector — JAMMA edge, JVS loom or a proprietary harness — plenty of makers kept one long after JAMMA arrived — see Identification above. → Wiring Check −5 V and +12 V too if the sound stage uses them. Suspected short: bring it up current-limited and find the hot spot.
4. /RESET. It must release after power-up. Held low = the CPU never starts. A 1–2 Hz loop is not the reset circuit, it is the watchdog: the CPU is crashing at boot, so look at the bus, not at the reset.
5. Clocks — the values expected on this platform.
- M68020 → 24.576 MHz (Main CPU)
No clock on the M68020 (24.576 MHz) and there is no point measuring anything else: the fault is the crystal, the divider, or the chip itself. That single measurement splits a dead board in two.
6. Bus. Activity on the main CPU's address lines tells you whether it is running or frozen. Frozen with good clocks and good reset → work RAM, bus buffers, ROMs.
7. It boots but the picture or the sound is wrong — that is another job: see Common faults on this page, then signal tracing.
Emulation & FPGA¶
- Emulation: MAME (
namco/namcos22.cpp) — long imperfect (textures/timing), now much better. - FPGA / MiSTer: no core (TR3 GPU + DSP, out of budget).
EPROM repair¶
68020 program (Super System 22) in 27C040 / 27C080 (MAME namco/namcos22.cpp):
Ridge Racer = 4× 27C040 · Time Crisis / Prop Cycle = 4× 27C080. C74/C76 MCU
protection + 3D customs; the 3D/texture data is in mask ROM.
Lineage¶
After the System 21 (untextured 3D), before the System 23 (1997). A rival to the Sega Model 2.
Photos / assets¶
(To add: System 22 crate, 68EC020, TR3 chipset, C352.)
Sources & attribution¶
-
Photo PCB Namco System 22 — Yaca2671, CC BY-SA 3.0, Wikimedia Commons — https://commons.wikimedia.org/wiki/File:Sys22_point_rom_pcb_01.jpg
-
MAME —
namco/namcos22.cpp(68EC020, 2× TMS320C25, E&S TR3 GPU, C352, texture mapping, games) — https://github.com/mamedev/mame - Arcade Otaku / Namco Wiki — Namco System 22 (TR3, texture mapping, Super 22, games) — https://wiki.arcadeotaku.com/w/Namco_System_22
- Wikipedia — Ridge Racer (1993) — CC-BY-SA — https://en.wikipedia.org/wiki/Ridge_Racer_(1993_video_game)
Review & corrections
How this space is used
Spotted a wrong value, an outdated procedure, a chip reference that does not match your board? Say so here, with what you observed (model, board revision, serial number, measurement). Every report is cross-checked against a source before anything changes — an unverifiable correction is published as “reported by …, not cross-checked” rather than silently applied.
Reading is open to everyone; posting requires signing in with Discord. Reports from the wiki's declared reviewers are handled first; anyone else's are read too, but go through a human before anything is changed.