choose pallette on title screen (atari logo key)

1 files changed, 19 insertions, 0 deletions

diff --git a/newtitle.s b/newtitle.s
index f52ac57..9eef9ed 100644
--- a/newtitle.s
+++ b/newtitle.s
@@ -19,6 +19,11 @@ screendata = $9000
 version:
  .incbin "ver.dat"
 
+colorchoices:
+ .byte $c0,$10,$00
+
+colorcount = (*-colorchoices)-1
+
  ; executable code here
 start:
  ; setup color registers
@@ -52,12 +57,26 @@ start:
  lda #$ff
  sta CH
 
+ ldx #0 ; X = index into color choices
+
  ; wait for user to press a key
 wait4key:
+ lda colorchoices,x
+ sta COLOR2
  lda CH
  cmp #$ff
  beq wait4key
+ cmp #39 ; atari logo key
+ bne keyok
+ dex
+ bpl x_ok
+ ldx #colorcount
+x_ok:
+ lda #$ff
+ sta CH
+ bne wait4key
 
+keyok:
  ; eat the keypress
  lda #$ff
  sta CH