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Namco System 11

Namco's first PlayStation-based hardware (1994): the end of the in-house 3D crates, now a cheap PS1 base. It's the cradle of Tekken and Soul Edge. Each game is locked by a KEYCUS chip — the real topic for conversions.

PCB Namco System 11

PCB Namco System 11 — photo by II...Richard...II, CC BY 3.0 (Wikimedia Commons).

Identification

Field Value
Manufacturer Namco
Year 1994 (Tekken)
Base Sony PlayStation (PS1)
Media game-specific ROM board
Security KEYCUS (custom C4xx chip per game)
I/O JAMMA / Namco

Architecture (≈ PS1)

Block Chip Role
CPU MIPS R3000A (~33.9 MHz) PlayStation base (+ GTE/MDEC)
GPU custom Sony (PS1) 2D/3D rendering
Sound Namco C352 (+ PS1 base) 32 PCM voices
Media game-specific ROM board + KEYCUS

Namco reuses the PS1 architecture (as Konami 573, Capcom ZN, Taito FX would): lower cost, easy arcade↔console ports (Tekken also shipped on PS1). Emulated in MAME (namco/namcos11.cpp).

Security (KEYCUS)

Each game has a KEYCUS chip (C4xx series) that the program queries: without the right one, no boot. It's the lock for any conversion — the chips and their per-game pairing are documented: → Namco System 11/12 — per-game KEYCUS · Namco converts guide.

Notable games

Tekken (1994), Tekken 2 (1995), Soul Edge (1995), Xevious 3D/G, Dunk Mania, Prime Goal EX, Star Sweep, Point Blank (Gun Bullet)…

Common faults

Symptom Likely cause Lead
Won't boot missing/wrong KEYCUS, ROM board contacts Check KEYCUS; see converts
Corrupt graphics video RAM / ROM board RAM test, contacts
No/partial sound C352 Sound-stage diagnosis
Lost settings RTC/config battery Replace
No image Power, R3000A, contacts Base diagnosis

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.

  • Battery 🟢: a save battery is fitted (settings/counters/RTC). A leaking battery corrodes traces — check and replace it before it leaks → save batteries.
  • 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 📺: PlayStation-based (Sony GPU) → standard ~15 kHz output, a 15 kHz chassis is fine. (Derived from the platform documented above — the screen configuration lives in the GPU device rather than the driver, so it is not measured here.)
  • FPGA / emulation: see the Emulation & FPGA section below.

Repair (technician)

  • KEYCUS (custom C4xx per game): without the correct KEYCUS chip the game won't boot — check before suspecting the logic.
  • PS1 base (R3000A + Sony GPU): PS1-type faults (recap, GPU/RAM).
  • Sound: Namco C352 (32-voice PCM) — diagnose the sound stage.
  • Capacitors: recap. ROM board: oxidised contacts → clean.

→ Methods: PCB fault-finding · Recap · EPROM · Traces & vias

Original manuals for games on this platform ✅

Manufacturer manuals for games running on this board. Beyond the instructions, they very often carry the full DIP settings, the connector pinout, the test procedure, the parts list and the expected voltages.

→ Full catalogue: service manuals, wiring & game manuals

DIP settings ✅

1 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 namcos11
Setting Position Options (default in bold)
DIP1 (Test) DIP SW2:1 Off · On
DIP2 (Freeze) DIP SW2:2 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. There is no measurement table for this platform — MAME's sources yield nothing usable for it. Any frequency quoted under Architecture on this page serves as a marker; otherwise compare against a working board rather than against a number: an invented value condemns healthy parts. → PCB diagnosis

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/namcos11.cpp).
  • FPGA / MiSTer: no core (a full PS1 base).

Lineage

After the System 22 (in-house 3D), Namco moves to PS1 — before the System 12 (Tekken 3, 1997) then the System 246/256 (PS2).

Photos / assets

(To add: System 11 board, ROM board, KEYCUS C4xx, C352.)

What the Tekken 2 kit manual establishes ✅

Read off the Namco America manual archived below, §1 Specifications.

Item What the manual requires
Power supply 150 W computer-grade · +5 VDC ±5 %, 5 A minimum · +12 VDC ±5 %, 2 A minimum
Harness 56-pin JAMMA type, ⚠️ key installed at pins H and 7
Monitor colour, horizontally mounted, taking RGB inputs from the kit PCB
Control panel 2 players: two black 8-way sticks · 4 red buttons (2 per player) · 4 yellow buttons (2 per player) · 2 start switches

The same prohibition as on the System 12 — but better explained

"The TEKKEN 2 PCB can be damaged by even the small internal voltage of a multimeter or similar device. Never test the PCB for conductivity with such devices."

⚠️ The word missing from the Tekken 3 manual is here: conductivity. What Namco rules out is the continuity test — ohmmeter mode, the one that injects a current into the circuit under test. The Tekken 3 wording is broader ("troubleshoot") but points at the same danger.

See the Tekken 3 manual's reservation on the System 12: this is not an isolated precaution. ⚠️ And it is not specific to Namco either: the earlier Moon Cresta manual from Nichibutsu carries the same prohibition and the same reason. It is a practice of the Japanese industry of the period, not one firm's custom.

What changed between System 11 and System 12

Both kit manuals follow the same template, which makes the comparison readable:

Tekken 2 — System 11 Tekken 3 — System 12
+5 V ±5 % ⚠️ +5 % / −1 % — tightened from below
+12 V ±5 %, 2 A ±5 %, 2 A — unchanged
Power 150 W 150 W — unchanged
Harnesses 56-pin JAMMA only 56-pin plus a 48-pin
Shielding not mentioned EMI box and two ferrite cores required

The System 12 therefore asks for a more stable supply and more constrained wiring than the System 11, at the same power.

Archived original documents ✅

Manufacturer documents archived locally, found on Internet Archive on 13 August 2026 and identified from their title page. ⚠️ The items declare no licence — kept for preservation, provenance named.

Sources & attribution

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.