Hardware Acronyms

Gamecube hardware acronyms for CubeDocumented project

Documented by Andrei Shestakov (org). Version 1.1. (22 Jan 2006) (original document hosted here: http://dolwin.emulation64.com/docs/acronyms.txt)

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AA

   Antialiasing. Rendering method, that makes polygon edges seem less sharpen,
   combining colors of nearby pixels.

AD16

   Mysterious EXI device.

AI

   Audio Interface. Hardware responsible for DMA playback of PCM buffer and
   DVD ADPCM streaming sound. AI hardware cannot mix sound channels or set
   channel volume for PCM DMA playback. These operations and more advanced
   sound effects are produced by DSP.

Apploader

   Small program on DVD to load main DOL executable.

AR, ARAM

   Auxiliary (Audio) Memory. 16 MB of slow (comapred to RAM) DRAM.
   Used for raw DSP sound data and as temporary space for textures.
   ARAM has DMA communication channel with main memory (RAM). Development
   boards has "ARAM Expansion" (additional 4, 16 or 32 MBs).

BAT

   Block Address Translation, PPC MMU translation mechanism. There are DBAT
   and IBAT special-purpose registers for data and instruction address 
   translation respectively.

BBA

   Broad-Band Adapter, GC's 10BaseT Ethernet Adapter.

BS

   Bootstrap Stage (from analogy with UNIX). Very first code, executed after
   GC hard reset.

BS2

   Bootstrap Stage 2. Same as IPL.

CR

   PPC Condition Register, stores result of integer comare operation, for
   conditional branch decision.

CRT

   C Run Time. C/C++ program environment (libraries and startup calls).

DOL

   Gamecube application (custom executable file format).

Dolphin

   Early development work name of Gamecube.

Dolphin OS

   Gamecube OS. Single user, single process, multithreaded. Linked together
   with any GC application ("hard-linked"), as library.

DSP

   Digital Signal Processor. Used to produce advanced sound on GC.
   DSP is integrated with GP in Flipper chip and has its own ROM.
   Developed by Macronix.

DI, DVD

   DVD hardware interface. GC DVD is actually microcontroller, based on MN-102
   CPU with proprietary firmware ROM. DVD is protected by non-standard barcodes
   and data encryption, which is decrypted on-the-fly by DVD controller. GC DVD
   cannot be read on usual PC hardware. Whole GC DVD stuff is developed by
   Matsushita.

EFB

   Embedded Framebuffer. 2MB of fast 1T-SRAM memory located inside Flipper.
   Used by GP's pixel engine to draw pixels. Later copied into XFB, for final
   TV-output.

EXI

   Expansion Interface. Gamecube peripherial devices bus, sort of USB
   architecture. Developed by Macronix. Devices drived by EXI: memory cards,
   broad-band adapter, real-time clock, bootrom, SRAM.

FIFO

   First-In-First-Out buffer to send GP commands and create GP command lists.

Flipper

   Gamecube Northbridge+Peripheral Hardware+Graphics Processor+Audio DSP.

FPR

   Floating Point Register. Gekko has 32 64-bit FPRs, named f0-f31.

FPSCR

   Floating Point Status and Control Register.

JTAG

   Hardware debug interface to CPU. You can connect some wires to CPU pins,
   to overwhelm it. Gekko has full support of IEEE 1149-1a-1993 JTAG standard.

GC, GCN, NGC

   Nintendo Gamecube.

GCM

   Gamecube Master Data (official term). GC DVD Image files.

Gekko

   Gamecube CPU, PowerPC 750-derivative processor with FPU extensions, called
   "Paired Single".

GP, GX

   Graphics Processor, the major part of Flipper chip. GP is fixed point
   state-machine. Developed by ArtX team.

GPR

   General Purpose Register. Gekko has 32 32-bit GPRs, named r0-r31. r1 often
   used as stack pointer (sp).

GX

   Software library, developed by Nintendo and ArtX, to drive GP hardware.
   Has many crossways with OpenGL (but more advanced).

HW2

   Common name of GC hardware. Number state for revision ("2" is production
   board).

IPL

   Initial Program Loader. Graphics shell, used to load game from DVD.

MC

   Memory Card, EXI device.

MI

   Flipper memory interface, plays role of "Nothbridge".

MMU

   PPC Memory Management Unit. Translates virtual address to physical.
   MMU has two translation mechanisms: block address translation and page table
   translation. Address translation for data access and instruction fetch is
   processed separately in DMMU and IMMU.

MSR

   Machine State Register. CPU status and control register.

MX

   Macronix Ltd. chips index. GC has many hardware parts, developed
   by Macronix, like DSP, EXI and bootrom chip.

PC

   Program Counter. PowerPC architecture does not define such term, but
   everyone is using it anyway, instead "CIA" (Current Instruction Address).

PCM

   Pulse Code Modulation, method commonly used in digital sound hardware.
   PCM sound parameters are: playback rate, bits per sample, sample format.
   GC AI can playback 32000/48000 Hz, 16-bit big-endian stereo samples via
   DMA.

PI

   Peripheral Interface. Set of hardware registers to control interrupts and
   hardware reset. There also "PI FIFO": hardware-driven FIFO buffer in RAM.

PM

   PowerPC Performance Monitor. Set of PPC special purpose registers used for
   speed profiling of applications.

PPC

   IBM PowerPC Architecture.

PTE

   Page Table Entry. Page table record, used to translate virtual address to
   physical.

RAM

   Main memory. GC has 24 MB of fast 1T-SRAM. Development boards has RAM
   extended up to 48 MB. Developed by MoSys.

ROM

   Read-only memory. GC has following ROMs: 2 MB encrypted bootrom, 128 KB
   DVD firmware, 4 KB DSP DROM, 8 KB DSP IROM.

RSW

   "Reset Switch", same as reset button. Seems early development GC models
   were equipped by switch, insted programmable reset button.

RTC

   Real-time clock. EXI device, counting seconds since 00:00 AM 2000.

SDK

   Software Development Kit. Full set of compilers, libraries and documentation
   for development on specified platform. Gamecube SDK contain development tools,
   like sound and texture convertors, and set of libraries for OS and hardware.
   Compiler is provided by Metrowerk's CodeWarrior. There also huge development
   board and paper documentation.

SI

   Serial Interface. Hardware responsible for communication with serial devices,
   such as GC controller and keyboard via serial I/O buffer.

SPR

   Special-purpose register. Set of registers, dedicated to operating system.
   Gekko has about 60 SPRs.

SR

   Segment Registers, used by MMU for virtual address translation.

SRAM

   Small amount of battery backuped memory for OS misc settings.

TLB

   PPC MMU Translation Lookaside Buffer, used to keep recently used page
   address translations. Gekko has 128 two-way set associative TLB for each
   MMU (DMMU and IMMU).

VI

   Video Interface. Hardware responsible for TV-out of framebuffer (XFB),
   and generating VBlank interrupt (actually can be configured to interrupt
   CPU at any beam location). Has support for light-gun, antialiasing of XFB
   by tap-filters and progressive video mode (480p).

WBUF

   Gekko Write Gather Buffer. Small cache for burst memory transactions.
   Used together with graphics FIFO to send GP commands.

XFB

   External Framebuffer, located in main memory. Used for final TV-out by VI.