X-Git-Url: http://git.joshuawise.com/fpgaboy.git/blobdiff_plain/ec7274034775dc5e053ff3c96bd141ac50b4fc81..ee31adcb22c5011aeaaa0149ee22fa18e45317a5:/diag.asm

diff --git a/diag.asm b/diag.asm
index c832ff2..e9fff6a 100644
--- a/diag.asm
+++ b/diag.asm
@@ -69,19 +69,33 @@ tiles:
 	db %11111100
 	db %00000000
 
+	db %01111100
+	db %11000110
+	db %11000010
+	db %11000000
+	db %11000010
+	db %11000110
+	db %01111100
+	db %00000000
+
+	db %11111100
+	db %11000110
+	db %11000110
+	db %11000110
+	db %11000110
+	db %11000110
+	db %11111100
+	db %00000000
+
 putscreen:
 	; Wait for vblank
 	call .vblwait
 
 	ld hl, $8000	; Copy two tiles.
 	ld de, tiles
-	ld c, $10
-.cloop:	push hl
-	ld h, d
-	ld l, e
-	ld a, [hl]
+	ld c, $20
+.cloop:	ld a, [de]
 	inc de
-	pop hl
 	ld [hli], a
 	ld [hli], a
 	dec c
@@ -93,9 +107,9 @@ putscreen:
 .vloop:	call .vblwait
 	ld c, $40
 	ld b, 0
-.loop:	inc b
-	ld a, b
-	and $01
+.loop:	ld a, b
+	inc b
+	and $03
 	ld [hli], a
 	ld a, h
 	cp $9C
@@ -127,30 +141,19 @@ vbl:
 	ld [$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: