WIP sky scroller #2

loader/samples/minexample/minexample.s

@@ -82,7 +82,7 @@ copy_start:
     sei
     lda #$35
     sta $01
-    jmp part_9
+    jmp CODE_START_ADDR
 
     .res loadraw - *
 .incbin "../../build/loader-c64.prg", 2
@@ -168,7 +168,7 @@ code_start:
     ;sta frame_delay
     ;jsr wait_loop
 
-    jsr intro
+    ; jsr intro
 
     lda #$0b
     sta $d011
@@ -200,6 +200,7 @@ code_start:
     jsr init_2x
     lda #$0b
     sta $d011
+    jmp part_9 ; TEMP
 
     jsr clr_txt
     ldx #<story_writ
@@ -507,6 +508,45 @@ code_start:
 part_9:
     jsr init_bmp
 
+    ; set up sprites to cover scrolling
+    lda #$ff
+    ldx #0
+:   sta $2000,x
+    sta $4000,x
+    inx
+    bne :-
+    .repeat 4, I
+        ldx #I*48+$58
+        stx $d000+I*2
+        stx $d008+I*2
+    .endrepeat
+    ldx #6
+:
+    lda #$42
+    sta $d001,x
+    lda #$d7
+    sta $d009,x
+    dex
+    dex
+    bpl :-
+    ldx #7
+:
+    lda #$80
+    sta $0ff8,x
+    lda #0
+    sta $63f8,x
+    sta $d027,x
+    dex
+    bpl :-
+    stx $d01d
+    stx $d015
+    inx
+    stx $d010
+    stx $d017
+    stx $d01b
+    stx $d01c
+    stx frame
+
     ldx #<skyscrname
     ldy #>skyscrname
     lda #$70
@@ -566,8 +606,14 @@ part_9:
     bpl :-
 
 :
-    stx $d020
+    lda #2
-    inx
+    sta frame_delay
+    jsr wait_loop_2x
+    lda frame
+    and #7
+    ora #$38
+    sta $d011
+    inc frame
     jmp :-
     jmp *
 
@@ -717,13 +763,27 @@ init_2x:
     lda #$00
     sta $d012
 
+:
+    bit $d011
+    bpl :-
+:
+    bit $d011
+    bmi :-
+    lda #51
+:
+    cmp $d012
+    bne :-
+
     lda #0
     sta $d01a
+    sta $dc0e
 
     lda #$63; <(985248/100)
     sta $dc04
     lda #$26; >(985248/100)
     sta $dc05
+    lda #$11
+    sta $dc0e
 
     lda $dc0d
     and #$81