X-Git-Url: http://git.joshuawise.com/fpgaboy.git/blobdiff_plain/dadf7990cbca24581bbb3c036df717dd59bdea41..3785d05a183aa8de851f361432c5da2cc8f11c16:/rom.asm

diff --git a/rom.asm b/rom.asm
index 2e98e13..7994d3e 100644
--- a/rom.asm
+++ b/rom.asm
@@ -4,7 +4,7 @@ main:
 	ld c, $51	; Note that we are alive.
 	ld a, $FF
 	ld [c],a
-
+	
 	ld sp, $DFFF
 
 	ld hl, signon
@@ -104,13 +104,22 @@ waitsw:
 	ld hl,waitswstr
 	call puts
 	
+	ld c, $07
+	ld a, $04	;start timer, 4.096KHz
+	ld [c], a
+	
 	ld c, $51
 	ld a, $00
 	ld [c],a
 	
+	ld e, a
+	
+.loop1:
+	push bc
+	call testa
+	pop bc
 	ld c, $51
 	ld b, $0
-.loop1:
 	ld a,[c]
 	cp b
 	jr z,.loop1
@@ -121,7 +130,24 @@ waitsw:
 	ret
 
 waitswstr:
-	db "Diagnostic ROM complete; flip switches to nonzero and then to zero to reset.",$0D,$0A,0
+	db "Diagnostic ROM complete; flip switches to nonzero and then to zero to reset. Expect A.",$0D,$0A,0
+
+testa:
+	ld c, $0F
+	ld a, [c]
+	ld b, $00
+	cp b
+	ret z
+	xor a
+	ld [c], a
+	ld a, $41
+	call putc
+	ld a, 1
+	add e
+	ld c, $51
+	ld [c], a
+	ld e, a
+	ret
 
 ; Core instruction basic acceptance tests.
 insntest:
@@ -232,9 +258,9 @@ insntest:
 
 ; Serial port manipulation functions.
 putc:
-	push af
 	ld b, 0
 	ld c, $50
+	push af
 .waitport:
 	ld a,[c]
 	cp b
@@ -247,6 +273,8 @@ puts:
 	ld a, [hli]
 	ld b, $00
 	cp b
-	ret z
+	jr z, .done
 	call putc
 	jr puts
+.done:
+	ret