The Pit
Disassembled by Karl Stiefvater
The Pit
The Pit (Zilec Electronics / Centuri / Taito, 1982) is a dig-and-escape game. You play an astronaut-explorer stranded on a forbidden planet. You dig down through a field of dirt and tunnels to a treasure chamber at the bottom, grab jewels — the sparse crystals and diamonds scattered in the dirt — and then climb back up to your ship to escape. The final stretch of the climb is the "Pit" crossing.
A rival craft has also landed, so three rival explorers roam the tunnels. They are hostile, and all three can be shot with your horizontal laser. Falling rocks and arrows, and the Pit crossing itself, *block* your movement but never cost a life — a life is lost only to enemy contact. The ubiquitous red field is diggable *dirt*, not treasure; the only collectibles are the sparse crystals and diamonds.
A board completes when you reach the top rung carrying at least one diamond: the ship descends to carry you off, and the board then rebuilds one level higher and faster. Run out of lives and the game is over, with a chance to enter your initials on the high-score table.
Navigation
- Hardware — CPU, memory map, I/O ports, LS259 control latch, sprite format
- Work RAM — the named work-RAM cells (0x8000–0x87FF)
- Main CPU code — the annotated Z80 disassembly
About this disassembly
This disassembly, RAM map, and game description were produced by AI and are verified against the original ROM and against MAME. The recovered code was checked to reproduce the ROM's own execution frame-for-frame, and the game model was confirmed by observing the real game running under MAME. It is offered here transparently, as AI work, precisely because it is machine-checked rather than hand-asserted — so verify it against that evidence. Project: https://github.com/qarl/arcade-js.
The disassembly covers the code reached from the two entry points — the reset vector (`0x0000`) and the vblank NMI (`0x0066`); ROM data tables (tilemaps, lookup tables, the drop queue, text) are shown as `DEFB` dat