menu progress (text engine)

snes/text.a65

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+.text
+#include "memmap.i65"
+print:
+	rep #$30 : .xl : .al
+	lda !print_x
+	and #$00ff
+	lsr
+	bcs print_bg1
+	ldx #!BG1_TILE_BUF ; for 2nd loop
+	phx
+	ldx #!BG2_TILE_BUF ; for 1st loop
+	phx
+	bra print_bg_cont
+print_bg1
+	ldx #!BG2_TILE_BUF+1 ; for 2nd loop
+	phx
+	ldx #!BG1_TILE_BUF ; for 1st loop da whoop
+	phx
+	bra print_bg_cont
+print_bg_cont
+	sta !print_x
+	lda !print_y
+	and #$00ff
+	asl
+	asl
+	asl
+	asl
+	asl
+	clc
+	adc !print_x
+	asl ; double the offset for WRAM addressing
+	tay	; zonday
+	plx
+	phy	; offset from tilemap start	
+	stx !print_x
+	clc
+	adc !print_x
+; we need to transfer to WRAM and from there to VRAM via DMA during VBLANK
+; because VRAM can only be accessed during VBLANK and forced blanking.
+	sta $2181
+	sep #$20 : .as
+	lda #$7f ;we really only need the lsb. full bank for clarity
+	sta $2183
+print_loop
+	ldx !print_src
+	lda !print_bank
+	pha 
+	plb
+	phx	; source addr
+print_loop_inner
+	lda !0,x
+	asl
+	sta @$2180
+	lda #$00
+	adc #$00
+	sta @$2180
+	inx
+	lda !0,x
+	beq print_loop2
+	inx
+	lda !0,x
+	beq print_loop2
+	bra print_loop_inner
+print_loop2
+	lda #$00
+	pha
+	plb	
+	rep #$30 : .al : .xl
+	ply	; source addr
+	iny
+	pla	; offset from tilemap start
+	plx	; other tilemap addr
+	stx !print_x
+	clc
+	adc print_x ; tilemap+offset
+	sta $2181
+	tyx
+	sep #$20 : .as
+	lda print_bank
+	pha
+	plb
+print_loop2_inner
+	lda !0,x
+	asl
+	sta @$2180
+	lda #$00
+	adc #$00
+	sta @$2180
+	inx
+	lda !0,x
+	beq print_end
+	inx
+	lda !0,x
+	beq print_end
+	bra print_loop2_inner
+print_end
+	lda #$00
+	pha
+	plb
+	rts
+