alu_ext

[fpgaboy.git] / diag.asm

diff --git a/diag.asm b/diag.asm
index e9a9f19a602d70f15445230fd9a960567194078f..e9fff6a2ed3476cc8741888d142b8c65421d17de 100644 (file)
--- a/diag.asm
+++ b/diag.asm
@@ -141,30 +141,19 @@ 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: