Finish sky scroller

loader/samples/minexample/minexample.s

@@ -562,7 +562,7 @@ part_9:
     ; $2000-$3fff buffer 0 bitmap
     ; $4000-$5fff buffer 1 bitmap
     ; $6000-$63ff buffer 1 tilemap
-    ; $6400-$67ff next buffer CRAM
+    ; $6400-$6417 next buffer CRAM
     ; $7000-$77ff tileset bitmap
     ; $7800-$78ff tileset tile colors
     ; $7900-$79ff tileset CRAM colors
@@ -604,17 +604,52 @@ part_9:
     ldx temp+1
     dex
     bpl :-
-
+    lda #0
+    sta cram_ptr
+    lda #$64
+    sta cram_ptr+1
 :
-    lda #2
+    lda $d011
-    sta frame_delay
+    bpl :-
-    jsr wait_loop_2x
+    lda #$38
-    lda frame
-    and #7
-    ora #$38
     sta $d011
+    lda #3
+    sta timer_mode
+@loop:
+    lda #0
+    sta vbl
+    lda frame
+    and #1
+    tax
+    jsr copybuf
+    jsr drawrow
+:
+    lda vbl
+    cmp #32
+    bcc :-
+    ; B U M   R U S H   C R A M C O P Y F U N K
+    ldy #23
+:   .repeat 16, I
+        lda $d808+(19-I)*40,y
+        sta $d808+(20-I)*40,y
+    .endrepeat
+    lda $6400,y
+    sta $d808+4*40,y
+    dey
+    bpl :-
     inc frame
-    jmp :-
+    lda frame
+    lsr a
+    lda #$38
+    ldx #3
+    bcc :+
+    lda #$80
+    ldx #2
+:
+    sta $d018
+    stx $dd00
+    jmp @loop
+@finish:
     jmp *
 
 drawrow:
@@ -829,7 +864,7 @@ irq_music:
     lda $dd00
     and #3
     sta @dd00_arc+1
-    lda #3
+    and #3
     sta $dd00
 
     inc vbl
@@ -879,6 +914,18 @@ irq_music:
     lda #1
     sta timer_reached
 :
+    lda timer_mode
+    cmp #3
+    bne @timer_done
+    lda vbl
+    lsr a
+    bcs @timer_done
+    lsr a
+    and #7
+    ora #$38
+    sta $d011
+
+@timer_done:
 
 @dd00_arc:
     lda #0
@@ -1370,6 +1417,81 @@ load_8000_zx02:
     pla
     jmp zx02
 
+copybuf:
+    lda @bsrclo,x
+    sta bmp_addr
+    lda @bsrchi,x
+    sta bmp_addr+1
+    lda @bdstlo,x
+    sta bmp_ptr
+    lda @bdsthi,x
+    sta bmp_ptr+1
+    lda @tsrclo,x
+    sta text_ptr
+    lda @tsrchi,x
+    sta text_ptr+1
+    lda @tdstlo,x
+    sta scr_ptr
+    lda @tdsthi,x
+    sta scr_ptr+1
+    ldx #16
+@loop:
+    ldy #23
+:   lda (text_ptr),y
+    sta (scr_ptr),y
+    dey
+    bpl :-
+    ldy #191
+:   lda (bmp_addr),y
+    sta (bmp_ptr),y
+    dey
+    bne :-
+    lda (bmp_addr),y
+    sta (bmp_ptr),y
+    ; math dumb cpu be struggling a lot here
+    lda text_ptr
+    sec
+    sbc #40
+    sta text_ptr
+    bcs :+
+    dec text_ptr+1
+:
+    lda scr_ptr
+    sec
+    sbc #40
+    sta scr_ptr
+    bcs :+
+    dec scr_ptr+1
+:
+    lda bmp_addr
+    sec
+    sbc #<320
+    sta bmp_addr
+    bcs :+
+    dec bmp_addr+1
+:
+    dec bmp_addr+1
+    lda bmp_ptr
+    sec
+    sbc #<320
+    sta bmp_ptr
+    bcs :+
+    dec bmp_ptr+1
+:
+    dec bmp_ptr+1
+    dex
+    bne @loop
+    rts
+
+@bsrclo:    .lobytes (15+4)*320+$2040, (15+4)*320+$4040 
+@bsrchi:    .hibytes (15+4)*320+$2040, (15+4)*320+$4040 
+@bdstlo:    .lobytes (16+4)*320+$4040, (16+4)*320+$2040 
+@bdsthi:    .hibytes (16+4)*320+$4040, (16+4)*320+$2040 
+@tsrclo:    .lobytes (15+4)*40+$0c08, (15+4)*40+$6008 
+@tsrchi:    .hibytes (15+4)*40+$0c08, (15+4)*40+$6008 
+@tdstlo:    .lobytes (16+4)*40+$6008, (16+4)*40+$0c08 
+@tdsthi:    .hibytes (16+4)*40+$6008, (16+4)*40+$0c08 
+
 story_writ:
 .res 11, ' '
 .byte "story written by"