ASM Init

; GB Initialization example
; RGBDS asm source
; David Pello 2012


INCLUDE "gbhw.inc"        ; include GB hardware definitions

; vBlank interrupt
SECTION "Vblank",HOME[$0040]
    reti     ; nothing, return

; Program starts here:
SECTION "start",HOME[$0100]
    nop
    jp      start

; ROM Header (gbhw.inc macro)
; MBC1 mapper, 64K rom, 8K RAM
ROM_HEADER  ROM_MBC1_RAM_BAT, ROM_SIZE_64KBYTE, RAM_SIZE_8KBYTE

; program begins
start:
    nop
    di                      ; disables interrupts
    ld      sp, $fffe       ; stack points to top of the high ram

init:
    ; palletes
    ld      a, %11100100    ; pallete colors from darker to
                            ; lighter, 11 10 01 00
    ld      [rBGP], a       ; write this at the background pallete register
    ld      [rOBP0], a      ; and at the first sprites pallete

    ; scroll
    ld      a, 0            ; write 0 to scroll registers X and Y
    ld      [rSCX], a       ; so visible screen is
    ld      [rSCY], a       ; at the top left of the background.

; now, you can turn off the LCD and load tiles, sprites, maps, etc