Medusa

Partial

Bally1981BY35bally.medusa.1981

OPDB IPDB bally/medusa-1981.mdbally/medusa-1981.json

Wire it up

what an authoring tool needs first
Bind this ROM
medusa

2 ROM sets resolve to this machine. Clones share the definition unless a hardware difference is listed.

Controller platform
pinmame.by35

PinMAME already reports logical active state. Do not invert again in the table — normally-closed is a physical fact recorded per switch, not a runtime transform.

Displays

No display inventory recorded yet.

Address space
Switches
8–41 (28)
Solenoids
1–19 (11)
Lamps
4–119 (72)

Coverage

Partial

Real evidence exists, but authoring requirements are still missing or in conflict. Verify before shipping a table.

Completion19%

Progress is derived from the fixed author-readiness requirements. It helps rank unfinished work, but only a 100% author-ready definition passes the publication gate.

Catalog Identity
validated
Address Enumeration
unknown
Semantic Naming
unknown
Physical Wiring
unknown
Mechanisms
unknown
Variant Coverage
candidate
Recreation Knowledge
unknown
Still missing · 13
Driver MappingInput EnumerationInput SemanticsOutput EnumerationOutput SemanticsDisplay InventoryMechanism InventoryMechanism BehaviorPolarityVariant DifferencesRecreation NotesProvenanceSpatial Placement

Switches

The addresses PinMAME reports as closed. Numbers are the public API values, not matrix hardware pins.

28 addresses

Switch map

Sequential addresses, grouped in columns of eight.

used unused
 
+0
+1
+2
+3
+4
+5
+6
+7
1–8
9–16
17–24
25–32
33–40
41–48
Hover or tap an address to identify it.
28 shown
# Name Device ID Evidence
8
Ball Release
switch.ball-release candidate
12
Sw12
switch.sw12 candidate
13
Sw13
switch.sw13 candidate
14
Sw14
switch.sw14 candidate
18
Rubber Bandsw18
switch.rubber-bandsw18 candidate
19
Sw19
switch.sw19 candidate
20
Sw20
switch.sw20 candidate
21
Sw21
switch.sw21 candidate
22
Sw22
switch.sw22 candidate
23
Sw23
switch.sw23 candidate
24
Sw24
switch.sw24 candidate
25
Sw25
switch.sw25 candidate
26
Sw26
switch.sw26 candidate
27
Sw27
switch.sw27 candidate
28
Sw28
switch.sw28 candidate
29
Sw29
switch.sw29 candidate
30
Sw30
switch.sw30 candidate
31
Sw31
switch.sw31 candidate
32
Sw32
switch.sw32 candidate
33
Spinner1
switch.spinner1 candidate
34
Right Sling Shot2
switch.right-sling-shot2 candidate
35
Right Sling Shot
switch.right-sling-shot candidate
36
Left Sling Shot
switch.left-sling-shot candidate
37
Bumper1
switch.bumper1 candidate
38
Bumper2
switch.bumper2 candidate
39
Bumper3
switch.bumper3 candidate
40
Bumper4
switch.bumper4 candidate
41
Sol DTRight Reset
switch.sol-dtright-reset candidate

Controlled devices

Everything the ROM can energise, grouped the way a table author builds it.

Coils, magnets & motors

11
11 shown
# Name Device ID Evidence
1
Sol Knocker
coil.sol-knocker candidate
2
Sol DTRight Reset
coil.sol-dtright-reset candidate
3
Sol DTTop Reset
coil.sol-dttop-reset candidate
4
Sol DTDrop43
coil.sol-dtdrop43 candidate
5
Sol DTDrop45
coil.sol-dtdrop45 candidate
6
Sol DTDrop47
coil.sol-dtdrop47 candidate
7
Sol Shield Post
coil.sol-shield-post candidate
8
Sol Outhole Kicker
coil.sol-outhole-kicker candidate
17
Solroundtargetson
coil.solroundtargetson candidate
18
BGGI
coil.bggi candidate
19
PFGI
coil.pfgi candidate

Lamps

72

Lamp map

Sequential addresses, grouped in columns of eight.

used unused
 
+0
+1
+2
+3
+4
+5
+6
+7
1–8
9–16
17–24
25–32
33–40
41–48
49–56
57–64
65–72
73–80
81–88
89–96
97–104
105–112
113–120
Hover or tap an address to identify it.
72 shown
# Name Device ID Evidence
4
L4 1
lamp.l4-1 candidate
10
L10
lamp.l10 candidate
12
L12
lamp.l12 candidate
14
L14
lamp.l14 candidate
15
L15
lamp.l15 candidate
17
L17
lamp.l17 candidate
18
L18
lamp.l18 candidate
19
L19
lamp.l19 candidate
20
L20
lamp.l20 candidate
21
L21
lamp.l21 candidate
22
L22
lamp.l22 candidate
23
L23
lamp.l23 candidate
24
L24
lamp.l24 candidate
25
L25
lamp.l25 candidate
26
L26
lamp.l26 candidate
28
L28
lamp.l28 candidate
30
L30
lamp.l30 candidate
31
L31
lamp.l31 candidate
33
L33
lamp.l33 candidate
35
L35
lamp.l35 candidate
36
L36
lamp.l36 candidate
37
L37
lamp.l37 candidate
38
L38
lamp.l38 candidate
39
L39
lamp.l39 candidate
40
L40
lamp.l40 candidate
41
L41
lamp.l41 candidate
42
L42
lamp.l42 candidate
43
L43
lamp.l43 candidate
44
L44
lamp.l44 candidate
46
L46
lamp.l46 candidate
47
L47
lamp.l47 candidate
49
L49
lamp.l49 candidate
51
L51
lamp.l51 candidate
52
L52
lamp.l52 candidate
53
L53
lamp.l53 candidate
54
L54
lamp.l54 candidate
55
L55
lamp.l55 candidate
56
L56
lamp.l56 candidate
57
L57
lamp.l57 candidate
58
L58
lamp.l58 candidate
59
L59
lamp.l59 candidate
60
L60
lamp.l60 candidate
62
L62
lamp.l62 candidate
63
L63
lamp.l63 candidate
65
L65
lamp.l65 candidate
66
L66
lamp.l66 candidate
67
L67
lamp.l67 candidate
68
L68
lamp.l68 candidate
69
L69
lamp.l69 candidate
70
L70
lamp.l70 candidate
71
L71
lamp.l71 candidate
81
L81
lamp.l81 candidate
82
L82
lamp.l82 candidate
83
L83
lamp.l83 candidate
84
L84
lamp.l84 candidate
85
L85
lamp.l85 candidate
86
L86
lamp.l86 candidate
87
L87
lamp.l87 candidate
97
L97
lamp.l97 candidate
98
L98
lamp.l98 candidate
99
L99
lamp.l99 candidate
100
L100
lamp.l100 candidate
101
L101
lamp.l101 candidate
102
L102
lamp.l102 candidate
103
L103
lamp.l103 candidate
113
L113
lamp.l113 candidate
114
L114
lamp.l114 candidate
115
L115
lamp.l115 candidate
116
L116
lamp.l116 candidate
117
L117
lamp.l117 candidate
118
L118
lamp.l118 candidate
119
L119
lamp.l119 candidate

Recreation notes

Working knowledge that has no schema field yet — edition differences, tuning values, pitfalls.

Coverage: partial - machine identity plus candidate-only I/O attachments. Playfield devices, wiring, mechanisms, and behavior are evidenced only as unverified candidates.

This record was promoted from the generated catalog stub stub.pinmame.medusa by the catalog-wide identity pass of 2026-08-29. The promotion resolves machine identity and carries the catalog's residual driver grouping over unchanged, the platform and device attachments below were added by the 2026-08-29/30 candidate passes and assert nothing beyond candidate provenance. Every requirement in the definition's coverage.missing is genuinely outstanding.

Identity

  • PinMAME catalog: root driver medusa, description "Medusa", manufacturer "Bally", catalog year "1981".
  • OPDB record G4xXQ-MDWW1 (IPDB 1565) names this machine "Medusa" (Bally, manufacture date 1981-02-04); the resolved identity rests on the agreement of the PinMAME catalog and this reviewed mapping.
  • The definition's driver list is exactly the clone tree PinMAME declares under medusa; whether every listed driver really runs on this physical machine is unverified.

Drivers this record holds

  • medusa (1981, Bally).
  • medusaa (2004, Bally / Oliver, clone of medusa).

PinMAME source contract (candidate)

  • The pinned PinMAME source declares medusa at src/wpc/by35games.c:1306 with machine module by35_mBY35_61BS; the definition declares controller platform pinmame.by35 from it.

VPX script candidates (candidate)

  • 3 retained community table script(s) declare this machine's driver; their extracted switch/lamp/solenoid/GI candidates are carried as 111 candidate devices. When curator work weighs sources, a retained script outranks emulator-derived candidates for runtime semantics, but every device here is still a candidate until a known-working table is verified against this exact physical machine.

What a curator must establish next

Full input, output, and display enumeration with semantic names; physical wiring and polarity; mechanism inventory and behavior; variant differences across the clone tree; recreation knowledge from a manual, schematic, or known-working table; runtime provenance; and a normalized spatial placement for every physical device. No manual, schematic, or runtime-harness evidence is retained for this machine yet; the candidate sections above are the only retained I/O evidence so far.

ROM sets

Every driver that resolves to this physical machine.

ROM set Description Year Parent Hardware
medusaaMedusa (Free Play) 2004medusa—
medusaMedusa 1981——

Parent set: medusa — clones share this definition unless a hardware difference is noted.

Pinball memory maps

External source LGPL-3.0-only2 maps

RAM layouts published by an independent project and mirrored here at a pinned commit. They are not part of this machine’s definition: nothing below was used as evidence for the definition, and none of it counts towards coverage. Check claims against the upstream project.

Upstream
tomlogic/pinball-memory-maps
Commit
d8693b9

This program makes use of content from the Pinball Memory Maps project.

system-rom-53-freeplay.map.json

bally-35-8Kv3format 0.8

maps/bally/as-2518-35/system-rom-53-freeplay.map.json

Applies to ROMs
medusaa
Also covers
bmxacybrnauaelektraafathomafbclassakosteelam_mpacaspyhuntavectoraxsandosa
Sections
adjustmentsauditsgame_statehigh_scores
Map JSONMap sourcePlatform JSONPlatform source

bally-35-8K defines the RAM layout this map’s offsets are read against — the map is not interpretable without it.

system-rom-53.map.json

bally-35-8Kv4format 0.8

maps/bally/as-2518-35/system-rom-53.map.json

Applies to ROMs
medusa
Also covers
bmxcybrnautelektrafathomfbclasskosteelm_mpacm_mpacbmedusafspyhuntrvectorxsandos
Sections
adjustmentsauditsgame_statehigh_scores
Map JSONMap sourcePlatform JSONPlatform source

bally-35-8K defines the RAM layout this map’s offsets are read against — the map is not interpretable without it.

Evidence

Every claim above traces to one of these. When they disagree: a known-working VPX script wins on controller addresses and causality, the manual wins on wiring and construction, pinned PinMAME wins on emulator routing and display layout.

  • PinMAME catalog

    BSD-3-Clause

    pinmame.catalog.8371478a7640

    PinmameGetGames

    8371478a7640
    by
    PinMAME contributors
    rev
    8371478a7640

  • PinMAME source

    BSD-3-Clause

    pinmame.core.8371478a7640

    src/wpc/by35games.c:1306 (machine module by35_mBY35_61BS)

    src/wpc/by35games.c
    by
    PinMAME contributors
    rev
    8371478a7640

  • VPX script

    vpx-script.20edde4ebf3d771b

    vpx-standalone-scripts: Medusa (Bally 1981) w VR Room v2.0.1/Medusa (Bally 1981) w VR Room v2.0.1.vbs

    15d112648a1b
    by
    Authors credited in Medusa (Bally 1981) w VR Room v2.0.1/Medusa (Bally 1981) w VR Room v2.0.1.vbs and repository contributors
    rev
    15d112648a1b
    sha256
    20edde4ebf3d…

  • VPX script

    vpx-script.fad0c2206c12b8ef

    vpxtable-scripts: Medusa (Bally 1981) v600.vbs

    0c036bb61b4b
    by
    Authors credited in Medusa (Bally 1981) v600.vbs and repository contributors
    rev
    0c036bb61b4b
    sha256
    fad0c2206c12…

  • VPX script

    vpx-script.1cf4d405f57b06e9

    vpxtable-scripts: Medusa v1.0.4.vbs

    0c036bb61b4b
    by
    Authors credited in Medusa v1.0.4.vbs and repository contributors
    rev
    0c036bb61b4b
    sha256
    1cf4d405f57b…

Something wrong or missing?

This definition still has 13 unmet requirements, listed under Coverage above. Fixes belong in the definition itself — editing on GitHub forks it for you and opens the pull request.

Cite a source for anything you change — a manual page, a line in a working VPX script, PinMAME source, or a reading from the machine's own service menu. Claims without provenance cannot be validated.

Edit the definition Edit the note Report a problem
Before you startCONTRIBUTING.mdschemas/machine.schema.jsondocs/MACHINE_DEFINITIONS_PLAN.md How to read a definition

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