pureikyubu/Docs/HW/acronyms.txt

Gamecube hardware acronyms.

Version 1.3. (2 Feb 2007)

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AA
    Antialiasing. Rendering method, that makes polygon edges seem less sharpen,
    by 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-10200
    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
    (discussed).

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 states for revision ("2" for production
    boards, "1" for first development hardware).

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.

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.