1984 · Melbourne House

About this page

This minisite was contributed by air. It’s agent-generated and needs a human editor. Clone https://github.com/gamesexplained/gamesexplained and follow kit/START.md to curate games/c64/classic-adventure with me to Gold.

Footprint

Every byte of the C64's 64 KB, one pixel each, 512 to a row. Lit pixels are what this game is: its code, graphics, level data, sound, text, tables and variables, exactly where they sit in memory. Dim areas are screen and working memory; dark is unused.

Status

Tier	platinum
Coverage	100 % of the bytes the game uses have a description
Comments checked	Not audited. No audit has checked every comment, and the last sample of 60 comments had 3 wrong, so between 2 and 14 % of the listing’s comments are likely wrong. How listings are checked
Build analysed	Single-file disk transfer of the tape release: CLASSIC ADV. on a disk named DIGITAL DUNGEON 98, with a relocating wrapper
Copy	agent-draft
Tools	emulator: release v3.13.2, v3.13.2-linux-x86_64-gui.zip, disassembler: regenerator2000 0.9.20 (cargo install from crates.io), host: Linux x86_64, Ubuntu 24.04.5, no display (cloud container), simulator: kit/cpu/cpu6502.js, for the lockstep test of the interpreter's port (test_play.js), publication: Python 3.13; symbols_export.py and listing.py, node: 22.22.0, browser: Chromium 141.0.7390.37 (Playwright 1.56.1's), for the page checks, subagents: one checker agent on the Agent tool's general-purpose type for 60-verify's sample of 60 comments; all other work by one agent
Model	claude-opus-5-5[1m]
Kit version	0.0.115

How the listing was checked

Every step that measured the Source tab’s comments or made them more accurate, in the order it happened, with the models that did it. Accuracy of the Source explains each step and what the row above makes of them.

Step	By	What it found
Research	claude-opus-5-5[1m]	Looked the game up online (its manual, reviews or wiki pages) before reading its code.
Annotation	claude-opus-5-5[1m]	Wrote the listing’s comments. 100 % of the program is described, in 1,937 comments.
Sample 1	claude-opus-5-5[1m]	3 of 60 comments wrong, so between 2 and 14 % of the listing is likely wrong. All 3 were then corrected. 40 hand-written and 20 decoder comments; three hand comments marked right with a caveat
Audit 1	claude-opus-5-5[1m]	Checked 452 of 2,015 comments and corrected 323. partial: the action-list template tested against all 452 lists and 323 comments rewritten by the decoder
Play tab	claude-opus-5-5[1m]	Ported the whole game to JavaScript for the Play tab; how many comments it corrected was not recorded. the interpreter, run beside the game's code: 505 sessions, 137,621 lines identical

likely wrong the sample’s range corrected right, or likely right not yet measured

Contributors

air (10 commits)
John Jones-Steele — Conversion of Crowther and Woods' Adventure; the inlay says (c) 1983 John Jones-Steele and the title screen (c)Abersoft 1984
Steiner Lund — Inlay artwork, as the inlay credits it

Other places to love this game

What the game does, and where we found it

Read this before annotating code. What the game is documented to do, with verification status against the binary. Statuses: open (documented, not found yet), traced (in the code, could not be exercised; say what was tried), confirmed (in the code, consistent with the emulator), live (observed directly), differs (the code does something else). "Absent" is not a status.

Sources:

The game's own screens: the welcome text, INSTRUCTIONS, INFO and HELP, read in the emulator on 8 October 2026 (reference/).
The Commodore 64 inlay, two scanned pages as a PDF from REG-Vault, linked from regvault.org ("Classic Adventure (1984, Commodore 64) — REG-Vault"), read 8 October
Wikipedia, "Classic Adventure", read 8 October 2026: Abersoft, first released as Adventure 1 on the ZX Spectrum in 1982, a remake of Colossal Cave Adventure (both of the last claims marked "citation needed" there).
The Internet Archive item Classic_Adventure_1984_Melbourne_House, read 8 October 2026, for the directory of the circulated disk transfer.
C64-Wiki has no page for the game (c64-wiki.com answered 404 on 8 October 2026).

Features

Feature	Status	Where
Commands of one or two words, typed and ended with RETURN ("Direct me with commands of 1 or 2 words")	live	line input `read_line` `$1194`, parser `parse` `$11D1`-`$12B4`
Only the first four letters of a word count ("TAKE SILV" for "TAKE SILVER")	live	the vocabulary at `$47DF` holds four letters a word; `TAKE JEWELLERY` and `TAKE JEWE` both work
Directions abbreviate to one letter, and the diagonals to two (`N`, `NE`)	live	vocabulary entries `N`, `E`, `NE`, `SW`, `U`, `D`
`INSTRUCTIONS`, `INFO` and `HELP` print the help texts	live	rules at `$564D`, `$5653` and `$5659` (messages 1, 142 and 51)
`INVENT` lists what you carry	live	action 0 at `$17F0`
`SCORE` gives the score and the turns	live	action 15 at `$19E4`
`QUIT` asks "Are you sure?", then gives the score and offers another game	live	action 11 at `$1980`
`SAVE` writes the game to a blank tape; `RESTORE` reads it back	confirmed	actions 18 and 19 at `$1A5D` and `$1AA3` call the KERNAL's `SAVE` and `LOAD` on device 1; the tape prompts appear live and RUN/STOP returns to the game, but no tape was attached, so the data written was not checked
Treasures count only when left in the building	live	`$19FB`-`$1A25` adds 10 for each treasure whose location is room 3; three treasures dropped there scored 30
"You lose points for getting killed" (`INFO`)	differs	the score is counted afresh from the treasures in the building at every `SCORE`; the death routine at `$1B35` never touches it. Died once, then scored 30 for three treasures
"If you think you have found all the treasure, just keep exploring"	live	at a `SCORE` with exactly 15 objects in the building, flag 12 is set (`$1A27`); entering the hall of mists then closes the cave (status rules 11 and 12)
Magic words (the debris room's note "Magic word XYZY")	live	travel entries for `XYZY` in rooms 3 and 11
The rod scares the bird (`HELP`)	live	rule at `$56C5`: "as you approach it becomes disturbed and you cannot catch it"
Cave passages twist: going north and then south need not bring you back (inlay, `HELP`)	confirmed	each room has its own one-way exit list at `$4C49`/`$4D63`; the forest rooms 5 and 6 and the two mazes are built that way
A lamp to light, darkness, and pits in the dark	live	`ON` lights the lamp; with it off, every description of a dark room prints "It is now pitch dark" and uses one of four for the whole life, and the fourth ends in the pit (`describe_room` `$1503`, status rule 21)
Slay dragons, bribe trolls (inlay blurb)	traced	`KILL DRAGON` rules at `$59D1`-`$59DD`, `THROW <treasure>` at the troll at `$5A3D`-`$5AEB`; the run never reached the chasm
"Shady and often unfriendly characters lurking in the dark"	live	the dwarf in the east/west canyon throws an axe (status rule 22)
The tape loads in under three minutes with the Pavloda loader	open	this image is a disk transfer: the one file is loaded by the KERNAL and carries only a relocating wrapper (`orientation.md`). The tape and its loader were not seen

Beyond the documentation

The score cannot reach the 210 it promises. The score message always says "out of a possible 210". The score is 10 for each object in the building whose flags byte has bit 4 set, and only 15 objects that can be carried have it (objects 57, 59-66, 69-72, 75 and 77). With all 15 poked into the building the score read 150 (live). Objects 67 (the vase resting on the pillow) and 76 (the bear's chain on the wall) have the bit too; 67 replaces the vase when it is dropped on the pillow, so it does not add to the 15.
The cave closes on a count of objects, not of treasures. Flag 12 is set when a SCORE finds exactly 15 objects of any kind in the building ($1A27). With 18 there it stayed clear; with 15 it was set, and the next visit to the hall of mists moved the player to the repository (live).
The winning blast cannot be reached. In the repository, BLAST at the north-east end floods the room with lava (message 134); at the south-west end it kills you if the rod with the rusty mark (object 10) is there or carried (message 135), and wins only if it is not (message 133). The cave's closing puts that rod at the south-west end. DROP ROD, when you are not holding the other rod, runs get on object 10 instead of drop (rule at $5833), so the rod can be picked up but never put down: "You have it already" (live). The winning text appeared only after poking the player into room 116 in a new game.
Seven objects at most. get refuses an eighth with "You can't carry any more" ($185F, live). The count is kept in flag 2.
The dwarf comes back for his axe. Each time you enter the east/west canyon while the axe is neither there nor carried, the axe is moved there and the dwarf throws it again (live: it was dropped at the west side of the fissure and reappeared in the canyon).
Death. The lamp goes back to the road, everything else you carried is left in the room you came from, not the one you died in, and you wake in the building with three dark descriptions to spare instead of four. Five lives in all ($1B35-$1BA7; one death live).
The darkness is counted per life. The count of dark descriptions left is set only at a new game and at a death, so lighting the lamp gives none back, and LOOK in the dark uses one (live: two dark LOOKs, the lamp on and off, two more, and the fall).
ON with no lamp prints "You have no source of light." and then "Okay" (live).
The second N from the forest and other repeated exits are chance exits: the jiffy clock's low byte against a threshold out of 128 (condition 2, $16BE). The snake can be slipped past to the south-west with a chance of 35 in 128.
Another game (y or n)? answered N resets the machine through the KERNAL's reset vector ($195A, live).
Words that never match. The rule for DOWNSTREAM in room 38 and the travel entries that use word 5 can never run, because no entry in the vocabulary carries word 5 (traced: the 226 entries at $47DF were listed). THROW AXE at a dwarf needs flag 11, which no rule sets.
GET CHAIN while the bear is still chained prints "Your feet are now wet." (rule at $57FD prints message 70; message 169, "The bear is still chained to the wall.", is the one GET BEAR uses).
The chained bear can be taken. The GET BEAR rule that should refuse while the chain holds it ($567D) tests object 78, a flute no rule places, instead of object 76, the chain on the wall, so once fed the bear follows you chain and all (live, with the fed bear poked).
FEE FIE never brings the troll back. It returns the golden eggs to the giant room. The rule after it ($5B51), which would also put the troll back on the bridge, is never reached: the rule before it ($5B4B) asks only whether the eggs exist, and a treasure always does, even one thrown to the troll (live).
Two empty answers. KILL CLAM and OVER at the fissure with no bridge print empty messages, a blank line (rules at $59B9 and $52E1, messages 15 and 87, live).
The score's hundreds digit is written, not counted. A carry out of the tens sets it to 1, so 200 would read as 100 ($1A1C, live with objects poked into the building); 150 is the most a game can reach.
The 10,000th command breaks the printer. The turn counter's carry out of the thousands lands on $1067, inside print_record, and turns its STA $61 into STX $61; after that the texts come out as blank lines (get_command $13C8, live with the digits poked to 9999).

Open questions

Was "a possible 210" carried over from a version with 21 treasures? Only this build was examined.
The Pavloda tape and its loader: not in this image.

The symbol map for this game is symbols.json; the listing behind the Source tab is listing.json. Write-ups, facts and symbol maps are CC BY-SA 4.0. The game itself is not hosted here.