Timer works.

[fpgaboy.git] / rom.asm

diff --git a/rom.asm b/rom.asm
index 2e98e136fb592519941823a6fa3a865d96b54f0d..5527ea889a0bd0a9e07c39024757aabc5a2be5ad 100644 (file)
--- 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 +104,20 @@ 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
        
+.loop1:
+       push bc
+       call testa
+       pop bc
        ld c, $51
        ld b, $0
-.loop1:
        ld a,[c]
        cp b
        jr z,.loop1
@@ -121,7 +128,19 @@ 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
+       ret
 
 ; Core instruction basic acceptance tests.
 insntest:
@@ -232,9 +251,9 @@ insntest:
 
 ; Serial port manipulation functions.
 putc:
-       push af
        ld b, 0
        ld c, $50
+       push af
 .waitport:
        ld a,[c]
        cp b
@@ -247,6 +266,8 @@ puts:
        ld a, [hli]
        ld b, $00
        cp b
-       ret z
+       jr z, .done
        call putc
        jr puts
+.done:
+       ret