Atari Jaguar Developer Reference

A cross-linked developer reference for the Atari Jaguar console, drawn from the original Atari Corp. documentation (1993–1995) and the community-restored “Version 10” editions. It covers the core system (the Tom and Jerry chip set) and the CD-ROM subsystem.

Start here

• New to the Jaguar? Begin at the System Architecture Overview.
• Looking for an address or register? See the Memory Map / Register List or the Complete Register List.
• Writing CD-ROM code? Start at the CD-ROM Subsystem Overview.

Core system

The Jaguar is a custom chip set — two ASICs plus a general-purpose CPU:

• Tom — graphics and video: sprite/bitmap display, RISC-accelerated 2D/3D drawing, and the Jaguar’s color model.
• Jerry — sound and I/O: RISC-driven audio synthesis and timers, plus the serial and controller interfaces.
• Motorola 68000 — the general-purpose CPU and system manager; the GPU, DSP, and Blitter carry the performance load.

Architecture & memory

• System Architecture Overview — the five processors and how they cooperate
• Memory Map / Register List — address space, banks, hardware registers
• Video & System Clocks, Timing — clock generation, NTSC/PAL timing, video ports
• Hardware Bugs & Warnings — known silicon bugs and cautions
• Cartridges, EEPROM Saves & ROM Building — cartridge port, on-cart saves, EPROM/EEPROM parts
• Connectors, Pinouts & Power — power supply, current draw, connector/schematic hub

CPU — Motorola 68000

The programmer’s model is documented end-to-end on one page:

• Programmer’s Model — overview — the 68000 in the Jaguar: clock, buses, byte order, memory rules & gotchas
• Registers & status register — data/address registers, the SR, privilege states
• Data organization — byte/word/long operands, alignment, big-endian order
• Addressing modes — the twelve 68000 addressing modes
• Instruction set — the full instruction list with condition-code effects
• Instruction timing — clock-cycle counts, EA calculation, exception times
• Exception processing — vector table, reset, interrupts, traps

Tom — graphics & video

• Object Processor — the display list engine (sprite + framebuffer hybrid)
• Graphics Processor (GPU) — the RISC graphics co-processor
• Blitter — block move/fill, line draw, Gouraud shading, Z-buffer
• CRY Color & Color Mapping — the CRY color model and RGB modes

Jerry — sound & I/O

• Digital Sound Processor (DSP) — the RISC sound co-processor
• Audio Subsystem & Synthesis — sample playback, timers, output
• Serial I/O — ComLynx, MIDI, Synchronous Serial
• Controllers & Controller Ports — Joypad, rotary, Team Tap, advanced controllers (read via Jerry’s JOYSTICK/JOYBUTS registers)

Peripherals

• Jaguar Voice Modem — voice/data modem interface, control flow, command reference

CD-ROM subsystem

• CD-ROM Subsystem Overview — what the Jaguar CD is and how it differs from other CD systems
• CD-ROM BIOS API — the calls your code uses to talk to the drive
• Disc & Data Format — sessions, tracks, frames, partition markers, audio
• Programming Procedures & Guidelines — boot, read, error handling, do’s & don’ts
• CD-ROM Hardware — drive module, schematic, connections

Programming examples

• Sample Programs — hardware demos (copyright-library samples excluded)

Reference

• Complete Register List
• RISC Instruction Set (GPU/DSP)
• Glossary
• Source Provenance — which source each page is built from

Source files

• Source files index — the original PDFs, with descriptions, notes, and download links

---

Sources: Atari Corp. Jaguar developer documentation, © Atari Corporation 1993–1995; “Version 10” restorations © Stephen Moss, 2021. Reproduced here for developer reference.