Irem M62 / M72 / M92 (R-Type & co.)
Irem's major arcade bases: M62 (Kung-Fu Master), M72 (R-Type), M92 (In
The Hunt, Ninja Baseball Bat Man). A V30/V33 (embedded x86) + Z80/V25 sound base,
with a protection i8751 MCU on many games. Cult shmups and action games.
Identification
| Field |
Value |
| Manufacturer |
Irem |
| Years |
1984 (M62) → 1993 (M107) |
| CPU |
NEC V20/V30/V33 (x86) per generation |
| Protection |
i8751 MCU (shares RAM with the CPU) on many games |
| Settings |
DIP |
The generations
| Hardware |
Year |
Games |
MAME driver |
| M62 |
1984 |
Kung-Fu Master, Kid Niki, Lode Runner, Spelunker |
irem/m62.cpp |
| M72 |
1987 |
R-Type, Ninja Spirit, Image Fight, X-Multiply, Dragon Breed, Hammerin' Harry |
irem/m72.cpp |
| M92 |
1991 |
R-Type Leo, In The Hunt, Gunforce, Blade Master, Undercover Cops, Ninja Baseball Bat Man, Major Title 2 |
irem/m92.cpp |
| M107 |
1993 |
Fire Barrel, Dream Soccer '94, World PK Soccer |
irem/m107.cpp |
- M72: V30 @ 8 MHz + sound Z80 + YM2151; an i8751 MCU sharing a RAM
($b0000-$b0fff) — the crux of the protection/conversion (see converts).
- M92: V33 @ 9 MHz + V30/V35 sound + GA20 (Irem) + Nanao GA21/GA22 customs.
→ Irem M72 / M92 converts (i8751 MCU).
Notable games
Kung-Fu Master (1984), R-Type (1987), Ninja Spirit, Image Fight, X-Multiply,
R-Type Leo (1992), In The Hunt, Undercover Cops, Ninja Baseball Bat Man, Gunforce…
Common faults
| Symptom |
Likely cause |
Lead |
| Crashes at boot |
i8751 MCU (protected games) |
Check the MCU; MAME dumps them |
| Corrupt sprites/planes |
Nanao customs / RAM |
RAM test, contacts |
| No/partial sound |
YM2151 / GA20 / Z80 |
Sound-stage diagnosis |
| Lost settings |
DIP |
Check the DIP bank |
| No image |
Power, V30/V33, harness |
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.
- 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 📺: M72: ~15.62 kHz / 55.0 Hz · M92: ~15.72 kHz / 60.0 Hz — standard resolution, a classic 15 kHz chassis is fine — the most common JAMMA case → tri-sync and upscalers.
(Computed from the MAME sources —
irem/m72.cpp + m92.cpp — pixel clock ÷ htotal.)
- FPGA / emulation: see the Emulation & FPGA section below.
Repair (technician)
- i8751 MCU: shares a RAM with the CPU (protection/I-O); without a healthy/dumped MCU
the game crashes → donor or dump (MAME). The crux of conversion (see converts).
- x86 CPU (V20/V30/V33) + Nanao GA21/GA22 customs, GA20/YM2151 sound: diagnose the
sound stage separately.
- Capacitors: recap sound + PSU filtering.
- Oxidised EPROM sockets: re-tin / 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 |
| V30 |
8 MHz |
CPU |
| V33 |
9 MHz |
CPU |
| YM2151 |
3.579545 MHz |
FM (sound) |
| Z80 |
3.579545 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.
DIP settings ✅
31 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 airduel
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
| Demo Sounds |
SW1:7 |
Off · On |
| Flip Screen |
SW2:1 |
Off · On |
| Coin Mode |
SW2:4 |
Mode 1 · Mode 2 |
| Coinage |
SW2:5,6,7,8 |
6C 1C · 5C 1C · 4C 1C · 3C 1C · 2C 1C · 3C 2C · 4C 3C · 1C 1C · 2C 3C · 1C 2C … |
DIP settings — MAME set bchopper
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
1 · 2 · 3 · 4 |
| Demo Sounds |
SW1:3 |
Off · On |
| Bonus Life |
SW1:4 |
80K 200K 350K · 100K 250K 400K |
| Flip Screen |
SW2:1 |
Off · On |
| Cabinet |
SW2:2 |
Upright · Cocktail |
| Coin Mode |
SW2:3 |
Mode 1 · Mode 2 |
| Difficulty |
SW2:4 |
Normal · Hard |
| Allow Continue |
SW2:5 |
No · Yes |
| Stop Mode |
SW2:6 |
Off · On |
| Invulnerability |
SW2:7 |
Off · On |
DIP settings — MAME set bmaster
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
1 · 2 · 3 · 4 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
| Bonus Life |
SW1:5 |
300k only · None |
DIP settings — MAME set dbreed
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
| Flip Screen |
SW2:1 |
Off · On |
| Cabinet |
SW2:2 |
Upright · Cocktail |
| Coin Mode |
SW2:3 |
Mode 1 · Mode 2 |
| Demo Sounds |
SW2:4 |
Off · On |
| Allow Continue |
SW2:5 |
No · Yes |
| Stop Mode |
SW2:6 |
Off · On |
DIP settings — MAME set dsoccr94j
| Setting |
Position |
Options (default in bold) |
| Player Power |
SW3:1,2 |
500 · 1000 · 1500 · 2000 |
| Time |
SW1:1,2 |
1:30 · 2:00 · 2:30 · 3:00 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
| Game Mode |
SW1:5 |
Match Mode · Power Mode |
| Starting Button |
SW1:6 |
Button 1 · Start Button |
DIP settings — MAME set gallop
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
| Allow Continue |
SW1:6 |
No · Yes |
| Demo Sounds |
SW1:7 |
Off · On |
| Flip Screen |
SW2:1 |
Off · On |
| Cabinet |
SW2:2,3 |
Upright · Upright (2P) · Cocktail |
| Coin Mode |
SW2:4 |
Mode 1 · Mode 2 |
DIP settings — MAME set gunforc2
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
1 · 2 · 3 · 4 |
| Difficulty |
SW1:3,4 |
Easy · Normal · Hard · Hardest |
DIP settings — MAME set gunforce
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
| Bonus Life |
SW1:5 |
15k 35k 75k 120k · 20k 40k 90k 150k |
DIP settings — MAME set hharry
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
| Continue Limit |
SW1:5 |
No · Yes |
| Allow Continue |
SW1:6 |
No · Yes |
| Demo Sounds |
SW1:7 |
Off · On |
| Flip Screen |
SW2:1 |
Off · On |
| Cabinet |
SW2:2,3 |
Upright · Upright (2P) · Cocktail |
| Coin Mode |
SW2:4 |
Mode 1 · Mode 2 |
DIP settings — MAME set hook
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
1 · 2 · 3 · 4 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
| Any Button to Start |
SW1:6 |
No · Yes |
DIP settings — MAME set imgfight
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Normal · Hard · Hardest · Debug Mode 2 lap |
| Flip Screen |
SW2:1 |
Off · On |
| Cabinet |
SW2:2 |
Upright · Cocktail |
| Coin Mode |
SW2:3 |
Mode 1 · Mode 2 |
| Demo Sounds |
SW2:4 |
Off · On |
| Stop Mode |
SW2:6 |
Off · On |
DIP settings — MAME set inthunt
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
| Any Button to Start |
SW1:6 |
No · Yes |
DIP settings — MAME set kengo
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
| Allow Continue |
SW1:6 |
No · Yes |
| Demo Sounds |
SW1:7 |
Off · On |
| Flip Screen |
SW2:1 |
Off · On |
| Coin Mode |
SW2:4 |
Mode 1 · Mode 2 |
DIP settings — MAME set lethalth
| Setting |
Position |
Options (default in bold) |
| Bonus Life |
SW3:1,2 |
500k 1000k · 700k 1500k · 700k 1500k 3000k 4500k · 1000k 2000k |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
| Continuous Play |
SW1:5 |
Off · On |
DIP settings — MAME set loht
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Demo Sounds |
SW1:3 |
Off · On |
| Flip Screen |
SW2:1 |
Off · On |
| Cabinet |
SW2:2 |
Upright · Cocktail |
| Coin Mode |
SW2:3 |
Mode 1 · Mode 2 |
| Difficulty |
SW2:4,5 |
Easy · Normal · Hard · Hardest |
| Stop Mode |
SW2:6 |
Off · On |
| Invulnerability |
SW2:7 |
Off · On |
DIP settings — MAME set m92_2player
| Setting |
Position |
Options (default in bold) |
| Allow Continue |
SW1:6 |
No · Yes |
| Demo Sounds |
SW1:7 |
Off · On |
| Flip Screen |
SW2:1 |
Off · On |
| Coin Slots |
SW2:3 |
Common · Separate |
| Coin Mode |
SW2:4 |
1 · 2 |
DIP settings — MAME set m92_3player
| Setting |
Position |
Options (default in bold) |
| Cabinet |
SW2:2 |
2 Players · 3 Players |
DIP settings — MAME set m92_4player
| Setting |
Position |
Options (default in bold) |
| Cabinet |
SW2:2 |
2 Players · 4 Players |
DIP settings — MAME set majtitl2
| Setting |
Position |
Options (default in bold) |
| Ticket Dispenser |
SW3:1 |
Off · On |
| Points Per Ticket |
SW3:2,3 |
1 Point/1 Ticket · 2 Points/1 Ticket · 5 Points/1 Ticket · 10 Points/1 Ticket |
| Deltronics Model |
SW3:8 |
DL 1275 · DL 4SS |
| Cabinet |
SW2:2 |
Upright · Cocktail |
| Given Holes/Stroke Play |
SW1:1 |
1 · 2 |
| Given Holes/Match or Skins |
SW1:2 |
1 · 2 |
| Difficulty |
SW1:3 |
Normal · Hard |
| Joystick Configuration |
SW1:4 |
Upright · Cocktail |
| Number of Joysticks |
SW1:5 |
2 Joysticks · 4 Joysticks |
| Any Button to Start |
SW1:6 |
No · Yes |
DIP settings — MAME set mysticri
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Easy · Normal · Hard · Hardest |
| Bonus Life |
SW1:5 |
15000 35000 60000 · 20000 50000 90000 |
DIP settings — MAME set nbbatman
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
1 · 2 · 3 · 4 |
| Difficulty |
SW1:3,4 |
Easy · Normal · Hard · Hardest |
| Any Button to Start |
SW1:6 |
No · Yes |
DIP settings — MAME set nspirit
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Easy · Normal · Hard · Hardest |
| Flip Screen |
SW2:1 |
Off · On |
| Cabinet |
SW2:2 |
Upright · Cocktail |
| Coin Mode |
SW2:3 |
Mode 1 · Mode 2 |
| Demo Sounds |
SW2:4 |
Off · On |
| Allow Continue |
SW2:5 |
No · Yes |
| Stop Mode |
SW2:6 |
Off · On |
| Invulnerability |
SW2:7 |
Off · On |
DIP settings — MAME set poundfor
| Setting |
Position |
Options (default in bold) |
| Round Time |
SW1:1,2 |
60 · 90 · 120 · 150 |
| Matches/Credit (2P) |
SW1:3 |
1 · 2 |
| Rounds/Match |
SW1:4 |
2 · 3 |
| Difficulty |
SW1:5 |
Normal · Hard |
| Trackball Size |
SW1:6 |
Small · Large |
| Demo Sounds |
SW1:7 |
Off · On |
| Flip Screen |
SW2:1 |
Off · On |
| Cabinet |
SW2:2,3 |
Upright · Upright (2P) · Cocktail |
| Coin Mode |
SW2:4 |
Mode 1 · Mode 2 |
| Coinage |
SW2:5,6,7,8 |
6C 1C · 5C 1C · 4C 1C · 3C 1C · 2C 1C · 3C 2C · 4C 3C · 1C 1C · 1 Coin/1 Credit, 1 Coin/Continue · 2C 3C … |
DIP settings — MAME set psoldier
| Setting |
Position |
Options (default in bold) |
| Any Button to Start |
SW1:6 |
No · Yes |
DIP settings — MAME set rtype
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Demo Sounds |
SW1:3 |
Off · On |
| Bonus Life |
SW1:4 |
50K 150K 250K 400K 600K · 100K 200K 350K 500K 700K |
| Flip Screen |
SW2:1 |
Off · On |
| Cabinet |
SW2:2 |
Upright · Cocktail |
| Coin Mode |
SW2:3 |
Mode 1 · Mode 2 |
| Difficulty |
SW2:4 |
Normal · Hard |
| Allow Continue |
SW2:5 |
No · Yes |
| Stop Mode |
SW2:6 |
Off · On |
| Invulnerability |
SW2:7 |
Off · On |
DIP settings — MAME set rtype2
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Easy · Normal · Hard · Hardest |
| Flip Screen |
SW2:1 |
Off · On |
| Demo Sounds |
SW2:2 |
Off · On |
| Coin Mode |
SW2:3 |
Mode 1 · Mode 2 |
| Cabinet |
SW2:4,5 |
Upright · Upright (2P) · Cocktail |
| Stop Mode |
SW2:6 |
Off · On |
DIP settings — MAME set rtypeleo
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
2 · 3 · 4 · 5 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
DIP settings — MAME set rtypep
| Setting |
Position |
Options (default in bold) |
| Demo Sounds |
SW1:3 |
Off · On |
DIP settings — MAME set thndblst
| Setting |
Position |
Options (default in bold) |
| Continuous Play |
SW1:5 |
On · Off |
DIP settings — MAME set uccops
| Setting |
Position |
Options (default in bold) |
| Lives |
SW1:1,2 |
1 · 2 · 3 · 4 |
| Difficulty |
SW1:3,4 |
Very Easy · Easy · Normal · Hard |
| Any Button to Start |
SW1:6 |
No · Yes |
DIP settings — MAME set xmultipl
| Setting |
Position |
Options (default in bold) |
| Difficulty |
SW1:1,2 |
Very Easy · Easy · Normal · Hard |
| Lives |
SW1:3,4 |
1 · 2 · 3 · 4 |
| Flip Screen |
SW2:1 |
Off · On |
| Cabinet |
SW2:2 |
Upright (single) · Cocktail · Upright (double) On · Upright (double) Off |
| Coin Mode |
SW2:3 |
Mode 1 · Mode 2 |
| Demo Sounds |
SW2:4 |
Off · On |
| Upright (double) Mode |
SW2:5 |
Off · On |
| Allow Continue |
SW2:6 |
No · Yes |
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 (
irem/m62.cpp, m72.cpp, m92.cpp, m107.cpp) — MCUs dumped.
- FPGA / MiSTer: cores available (M72 R-Type & co., M92, M62 per games).
EPROM repair
Program on a daughterboard: 27C512 (M72) → 27C010/020 (M92). Game-by-game program
EPROM table (+ per-game i8751 MCU): Irem M72/M92 converts.
Lineage
Irem, a shmup great — contemporary with Toaplan/Konami. For MCU de-protection and
conversion: see Irem M72/M92 converts.
Photos / assets
(To add: M72 (R-Type) board, i8751 MCU, Nanao customs.)
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.