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Sega X-Board

Sega's super scaler evolution (1987): 2× 68000 + very fast scaled sprites, for AM2's "sensation" games — After Burner, Thunder Blade, Super Monaco GP… Often in motion cabinets (After Burner's hydraulic cockpit). The successor to the Super Scaler, before the Y-Board.

Identification

Field Value
Manufacturer Sega (AM2)
Year 1987
Type super-scaler pseudo-3D (scaled sprites)
Cabinets often motion / deluxe (cockpit)

Architecture

Block Chip Clock Role
CPU ×2 Motorola 68000 ~12.5 MHz master (game) + slave (objects/road)
Sound CPU Zilog Z80 drives the sound
Sound Yamaha YM2151 (FM) + SegaPCM FM music + samples
Video Sega sprite-zoom ASIC hundreds of scaled sprites

Protection & de-suicide

The X-Board catalogue is mixed:

  • Unencrypted: After Burner, After Burner II, Thunder Blade (bare 68000).
  • FD1094-encrypted (battery module): Super Monaco GP, Line of Fire, GP Rider, Racing Herodead battery = suicide. De-suicide = decrypted ROM / re-key. → Sega X / Y-Board (converts) · System 16 FD1094.

EPROM repair: 68000 program in 27C010 (program in 27C010, FD1094-encrypted on many X-Boards) → game-by-game EPROM table.

Notable games

After Burner / After Burner II (1987), Thunder Blade (1987), Last Survivor, Line of Fire (1989), Racing Hero, Super Monaco GP (1989), GP Rider (1990).

Common faults

Symptom Likely cause Lead
Black screen / stuck boot FD1094: dead key battery (encrypted games) De-suicide (decrypted ROM / re-key)
Sprites no longer zoom zoom ASIC / sprite RAM Video diagnosis
No sound Z80 / YM2151 / SegaPCM Sound-stage diagnosis
Cabinet motion dead motion board / actuators Mechanical diagnosis
No image Power, dual 68000, 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.

  • Anti-suicide 🟠: some games/variants of this platform do suicide (battery-backed key) — see the dedicated section above to find out whether yours is affected. If so, the durable route is de-suicidingconversions and de-suiciding, not merely replacing the battery → 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 📺: ~15.62 kHz / 59.6 Hz — standard resolution, a classic 15 kHz chassis is fine — the most common JAMMA case → tri-sync and upscalers. (Computed from the MAME sources — sega/segaxbd.cpp — pixel clock ÷ htotal.)
  • FPGA / emulation: see the Emulation & FPGA section below.

Repair (technician)

  • FD1094 (battery module) on some (Super Monaco GP, Line of Fire, GP Rider…): flat battery = suicide (dead game, healthy hardware). Replace the battery without cutting the key (piggyback); otherwise de-suicidebackup batteries.
  • Dual 68000 (game + objects/road): a freeze = one of the CPUs / its RAM → separate diagnosis.
  • Sound: Z80 + YM2151 + SegaPCM — diagnose the sound stage.
  • Capacitors: recap PSU + audio filtering. Oxidised EPROM sockets: 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
M68000 12.5 MHz main CPU
YM2151 4 MHz FM (sound)
Z80 4 MHz · 8 MHz sound CPU (usually)

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.

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 ✅

11 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 abcop
Setting Position Options (default in bold)
Credits SWB:1 1 to Start, 1 to Continue · 2 to Start, 1 to Continue
Demo Sounds SWB:2 Off · On
Allow Continue SWB:3 No · Yes
Time SWB:5,6 Easy · Normal · Hard · Hardest
Difficulty SWB:7,8 Easy · Normal · Hard · Hardest
DIP settings — MAME set aburner
Setting Position Options (default in bold)
Cabinet Type SWB:1,2 Moving Deluxe · Moving Standard · Upright
Demo Sounds SWB:3 Off · On
Lives SWB:5 3 · 3x Credits
Allow Continue SWB:6 No · Yes
Difficulty SWB:7,8 Easy · Normal · Hard · Hardest
DIP settings — MAME set aburner2
Setting Position Options (default in bold)
Coin A SWA:1,2,3,4 7C 1C · 6C 1C · 5C 1C · 4C 1C · 3C 1C · 2C 1C · 2 Coins/1 Credit, 3/2, 5/3, 6/4 · 2 Coins/1 Credit, 4/3 · 1C 1C · 1 Coin/1 Credit, 5/6 …
Coin B SWA:5,6,7,8 7C 1C · 6C 1C · 5C 1C · 4C 1C · 3C 1C · 2C 1C · 2 Coins/1 Credit, 3/2, 5/3, 6/4 · 2 Coins/1 Credit, 4/3 · 1C 1C · 1 Coin/1 Credit, 5/6 …
Cabinet Type SWB:1,2 Moving Deluxe · Moving Standard · Upright 1 · Upright 2
Throttle Lever SWB:3 No · Yes
Lives SWB:4,5 3 · 4 · 3x Credits · 4x Credits
Allow Continue SWB:6 No · Yes
Difficulty SWB:7,8 Easy · Normal · Hard · Hardest
DIP settings — MAME set gprider
Setting Position Options (default in bold)
Cabinet SWB:1,2 Ride On · Upright
ID No. SWB:4 Main · Slave
Demo Sounds SWB:5 Off · On
Difficulty SWB:7,8 Easy · Normal · Hard · Hardest
DIP settings — MAME set gprider_double
Setting Position Options (default in bold)
Cabinet SWB:1,2 Ride On · Upright
ID No. SWB:4 Main · Slave
Demo Sounds SWB:5 Off · On
Difficulty SWB:7,8 Easy · Normal · Hard · Hardest
DIP settings — MAME set lastsurv
Setting Position Options (default in bold)
I.D. No SWB:1,2 1 · 2 · 3 · 4
Network SWB:3,4 Off · On (2) · On (4)
Difficulty SWB:5,6 Easy · Normal · Hard · Hardest
Demo Sounds SWB:7 Off · On
Coin Chute SWB:8 Single · Twin
DIP settings — MAME set loffire
Setting Position Options (default in bold)
Language SWB:1 Japanese · English
Cabinet SWB:2 Cockpit · Upright
2 Credits to Start SWB:3 Off · On
Difficulty SWB:4,5 Easy · Normal · Hard · Hardest
Allow Continue SWB:6 No · Yes
Demo Sounds SWB:7 Off · On
Coin Chute SWB:8 Single · Twin
DIP settings — MAME set rachero
Setting Position Options (default in bold)
Credits SWB:1 1 to Start, 1 to Continue · 2 to Start, 1 to Continue
Demo Sounds SWB:2 Off · On
Allow Continue SWB:3 No · Yes
Time SWB:5,6 Easy · Normal · Hard · Very Hard
Difficulty SWB:7,8 Easy · Normal · Hard · Very Hard
DIP settings — MAME set smgp
Setting Position Options (default in bold)
Machine ID SWB:1,2,3 1 · 2 · 3 · 4 · 5 · 6 · 7 · 8
Number of Machines SWB:4,5,6 1 · 2 · 3 · 4 · 5 · 6 · 7 · 8
Cabinet SWB:7,8 Deluxe · Cockpit · Upright
DIP settings — MAME set thndrbd1
Setting Position Options (default in bold)
Cabinet Type SWB:1 Deluxe · Standing
Demo Sounds SWB:2 Off · On
Time SWB:3 30 sec · 0 sec
Lives SWB:4,5 2 · 3 · 4 · 5
Allow Continue SWB:6 No · Yes
Difficulty SWB:7,8 Easy · Normal · Hard · Hardest
DIP settings — MAME set thndrbld
Setting Position Options (default in bold)
Cabinet Type SWB:1 Econ Upright · Mini Upright
Demo Sounds SWB:2 Off · On
Time SWB:3 30 sec · 0 sec
Lives SWB:4,5 2 · 3 · 4 · 5
Allow Continue SWB:6 No · Yes
Difficulty SWB:7,8 Easy · Normal · Hard · Hardest

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

Emulation & FPGA

  • Emulation: MAME (sega/segaxbd.cpp) — FD1094 included.
  • FPGA / MiSTer: no dedicated core (complex super scaler) → MAME.

Lineage

After the Super Scaler (Hang-On/OutRun), before the Y-Board (Galaxy Force). Contemporary with the System 16.

Photos / assets

(To add: X-Board, dual 68000, zoom ASIC, FD1094 module.)

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.