; Made by Alessandro Lo-Presti (Agilo) on Januari 22, 2008.
; Enable rumble feature when pressing C button.


.orgfill 0x1460             ; Start of General Purpose RAM.

.orgfill 0x2100             ; Start of ROM space.
.db "MN"                    ; ROM ID (do not change or validation will fail).
.include "irq.asm"          ; Game cart IRQ vectors.


; Pokemon Mini game header.
.orgfill 0x219E             ; 0x219E - 0x21A3 must be empty.
.orgfill 0x21A4             ; Start of "NINTENDO" string.
.db "NINTENDO"              ; Magic signature checked by the BIOS.
.db "RMBL"                  ; Game code, 4 bytes.
.db "RumbleOnC"             ; Name of ROM, 12 chars max.

.orgfill 0x21BC             ; Will contain the following string:
.db "2P"                    ; At this time it's unknown what "2P" stands for.

.orgfill 0x21D0             ; End of rom header, start of program code.
.include "irqhandlers.asm"  ; Game cart IRQ routine handlers.


; Code entry point.
start:
 movw	sp, 0x2000 ; Set SP to end of general purpose RAM (stack grows down).
 movw	nn, 0x2000 ; NN register points to hardware registers.

 ; Enable primary interrupts on all keys.
 movb	[nn+0x21], 0x0C

 ; Enable secondary interrupt for the power button (CPU will jump to 0x215C).
 movb	[nn+0x25], 0x80

 ; Clear all flags.
 movb	flags, 0


; Logics start here.
game_end:
 ; Check if C-button was pressed and rumble if so.
 test	[nn+0x52], (1<<2)
 jnz	_disable_rumble

 ; Enable rumble.
 or	[nn+0x61], 0x10
 jmp	game_end

_disable_rumble:
 ; Disable rumble.
 movb	[nn+0x61], 0x64
 jmp	game_end