Dual boot ROM support, and the first proof that cellular ram works!

[fpgaboy.git] / fpgaboot.asm

diff --git a/fpgaboot.asm b/fpgaboot.asm
new file mode 100644 (file)
index 0000000..a923657
--- /dev/null
+++ b/fpgaboot.asm
@@ -0,0 +1,38 @@
+       SECTION "boot", HOME[$0]
+       ld a, $AA
+       ld [$FF51], A   ; Poke the LEDs
+       
+       ; Write a little bit to the RAM
+       ld H, $01
+       ld L, $00
+       ld A, $00
+       ld [HLI], A
+       ld [HLI], A
+       ld [HLI], A
+       ld [HLI], A
+       ld [HLI], A
+       ld [HLI], A
+       ld [HLI], A
+       ld [HLI], A
+       
+       ld a, $55
+       ld [$FF51], A   ; Poke the LEDs
+       
+       ld A, $FF
+       ld [HLI], A
+       ld [HLI], A
+       ld [HLI], A
+       ld [HLI], A
+       ld [HLI], A
+       ld [HLI], A
+       ld [HLI], A
+       ld [HLI], A
+       
+       ld H, $00
+       ld L, $00
+       ld [HL], $01    ; Select the GB boot rom
+       rst $00         ; Boot
+       
+       SECTION "a", HOME[$100]
+       nop     ; Make sure we don't overflow.
+       
\ No newline at end of file