Kodewerx

arch n64.cpu
endian msb
output "@party2016.n64", create
fill 1052672
include "N64.INC"
include "N64_GFX.INC"

origin  $00000000
base    $A4000000

// N64 Header (64 bytes)
db $80                      // Initial PI_BSB_DOM1_LAT_REG Value
db $37                      // Initial PI_BSB_DOM1_PGS_REG Value
db $12                      // Initial PI_BSB_DOM1_PWD_REG Value
db $40                      // Initial PI_BSB_DOM1_PGS_REG Value
dd $0000000F                // Initial clock rate
dd BootcodeStart            // Boot address (normally this is in RDRAM)
dd $00001444                // Release offset
db "CRC1"                   // CRC1
db "CRC2"                   // CRC2
dd $00000000                // Unknown
dd $00000000                // Unknown
db "@PARTY2016          "   // Program title (20 bytes)
dd $00000000                // Unknown
db $00                      // Unknown
db $00                      // Unknown
db $00                      // Unknown
db $00                      // Developer ID code "N" = Nintendo
dw $0000                    // Cartridge ID code
db $00                      // Country code
db $00                      // Unused

BootcodeStart:
// Write 8 to $BFC007FC. This is supposed to stop the N64 from freezing after a
// couple of seconds. Don't ask me why, I just read it on the internet.
    li      r1, 8
    lui     r2, $BFC0
    sw      r1, $07FC (r2)

// Initialize the screen buffer
    ScreenNTSC(320, 240, BPP32, $A0100000)
   
PaintScreen:
    lui     r1, $A010
    lui     r2, $0004
    ori     r2, r2, $B000

DrawLoop:
    sw      r1, $0000 (r1)
    bne     r1, r2, DrawLoop
    addiu   r1, r1, 4

    j       PaintScreen

macro ScreenNTSC(width,height, status, origin) {
  lui a0,VI_BASE // A0 = VI Base Register ($A4400000)
  li t0,{status}      // T0 = Status/Control
  sw t0,VI_STATUS(a0) // Store Status/Control To VI Status Register ($A4400000)
  la t0,{origin}      // T0 = Origin (Frame Buffer Origin In Bytes)
  sw t0,VI_ORIGIN(a0) // Store Origin To VI Origin Register ($A4400004)
  lli t0,{width}      // T0 = Width (Frame Buffer Line Width In Pixels)
  sw t0,VI_WIDTH(a0)  // Store Width To VI Width Register ($A4400008)
  lli t0,$200         // T0 = Vertical Interrupt (Interrupt When Current Half-Line $200)
  sw t0,VI_V_INTR(a0) // Store Vertical Interrupt To VI Interrupt Register ($A440000C)
  lli t0,0                    // T0 = Current Vertical Line (Current Half-Line, Sampled Once Per Line = 0)
  sw t0,VI_V_CURRENT_LINE(a0) // Store Current Vertical Line To VI Current Register ($A4400010)
  li t0,$3E52239      // T0 = Video Timing (Start Of Color Burst In Pixels from H-Sync = 3, Vertical Sync Width In Half Lines = 229, Color Burst Width In Pixels = 34, Horizontal Sync Width In Pixels = 57)
  sw t0,VI_TIMING(a0) // Store Video Timing To VI Burst Register ($A4400014)
  lli t0,$20D         // T0 = Vertical Sync (Number Of Half-Lines Per Field = 525)
  sw t0,VI_V_SYNC(a0) // Store Vertical Sync To VI V Sync Register ($A4400018)
  lli t0,$C15         // T0 = Horizontal Sync (5-bit Leap Pattern Used For PAL only = 0, Total Duration Of A Line In 1/4 Pixel = 3093)
  sw t0,VI_H_SYNC(a0) // Store Horizontal Sync To VI H Sync Register ($A440001C)
  li t0,$C150C15           // T0 = Horizontal Sync Leap (Identical To H Sync = 3093, Identical To H Sync = 3093)
  sw t0,VI_H_SYNC_LEAP(a0) // Store Horizontal Sync Leap To VI Leap Register ($A4400020)
  li t0,$6C02EC        // T0 = Horizontal Video (Start Of Active Video In Screen Pixels = 108, End Of Active Video In Screen Pixels = 748)
  sw t0,VI_H_VIDEO(a0) // Store Horizontal Video To VI H Start Register ($A4400024)
  li t0,$2501FF        // T0 = Vertical Video (Start Of Active Video In Screen Half-Lines = 37, End Of Active Video In Screen Half-Lines = 511)
  sw t0,VI_V_VIDEO(a0) // Store Vertical Video To VI V Start Register ($A4400028)
  li t0,$E0204         // T0 = Vertical Burst (Start Of Color Burst Enable In Half-Lines = 14, End Of Color Burst Enable In Half-Lines = 516)
  sw t0,VI_V_BURST(a0) // Store Vertical Burst To VI V Burst Register ($A440002C)
  lli t0,($100*({width}/160)) // T0 = X-Scale (Horizontal Subpixel Offset In 2.10 Format = 0, 1/Horizontal Scale Up Factor In 2.10 Format)
  sw t0,VI_X_SCALE(a0)        // Store X-Scale To VI X Scale Register ($A4400030)
  lli t0,($100*({height}/60)) // T0 = Y-Scale (Vertical Subpixel Offset In 2.10 Format = 0, 1/Vertical Scale Up Factor In 2.10 Format)
  sw t0,VI_Y_SCALE(a0)        // Store Y-Scale To VI Y Scale Register ($A4400034)
}