Cut 1 at an onboard bootloader

[fpgaboy.git] / diag.asm

diff --git a/diag.asm b/diag.asm
index e9a9f19a602d70f15445230fd9a960567194078f..d269b25c1e38b186b7e9f62a700fe7fb9de181e9 100644 (file)
--- a/diag.asm
+++ b/diag.asm
@@ -33,6 +33,9 @@ main:
        ld hl, signon
        call puts
 
+       ld a, $91
+       ld [$FF40], a
+
        call putscreen
        
        ei
@@ -88,6 +91,9 @@ tiles:
        db %00000000
 
 putscreen:
+       LD A,$fc                ; $001d  Setup BG palette
+       LD [$FF47],A    ; $001f
+
        ; Wait for vblank
        call .vblwait
 
@@ -141,30 +147,19 @@ vbl:
        ld [$FF0F], a
 
        ld a, [$FF51]
-       ld b, a
-       and $80
-       cp $80
-       jr nz, .nothing
-       ld c, $0
+       bit 7, a
+       jr z, .nothing
 
-       ld a, b
-       and $1
-       cp c
+       bit 0, a
        call nz, .scyup
        
-       ld a, b
-       and $2
-       cp c
+       bit 1, a
        call nz, .scydown
        
-       ld a, b
-       and $4
-       cp c
+       bit 2, a
        call nz, .scxup
        
-       ld a, b
-       and $8
-       cp c
+       bit 3, a
        call nz, .scxdown
 
 .nothing:
@@ -326,8 +321,8 @@ waitsw:
        ld a,[c]
        cp $0
        jr z,.loop1
-.loop2:
-       ld a,[c]
+
+.loop2:        ld a,[c]
        cp $0
        jr nz,.loop2
        ret