X-Git-Url: http://git.joshuawise.com/fpgaboy.git/blobdiff_plain/f6fa1d6e1393de5d18302b8674ed1616afdfcefb..39a68cde9f2a76dabfcc9d7654f212ad1d7b356a:/diag.asm diff --git a/diag.asm b/diag.asm index 8e09874..7f06de0 100644 --- a/diag.asm +++ b/diag.asm @@ -32,6 +32,8 @@ main: ld hl, signon call puts + + call putscreen ei @@ -48,6 +50,25 @@ main: signon: db $0D,$0A,$1B,"[1mFPGABoy Diagnostic ROM",$1B,"[0m",$0D,$0A,0 +putscreen: + ld a, $FF ; Copy two tiles. + ld hl, $8000 + ld [hli], a + ld [hli], a + xor a + ld [hli], a + ld [hli], a + + ld hl, $9800 +.loop: ld a, $FF + ld [hli], a + xor a + ld [hli], a + ld a, h + cp $9C + jp nz,.loop + ret + vbl: PUSH AF PUSH BC