dos33fsprogs/pt3_player/text_print.s

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2019-05-07 00:16:45 +00:00
;================================
; htab_vtab
;================================
; move to CH/CV
htab_vtab:
lda CV
asl
tay
lda gr_offsets,Y ; lookup low-res memory address
clc
adc CH ; add in xpos
sta BASL ; store out low byte of addy
lda gr_offsets+1,Y ; look up high byte
adc DRAW_PAGE ;
sta BASH ; and store it out
; BASH:BASL now points at right place
rts
;================================
; move_and_print
;================================
; move to CH/CV
move_and_print:
jsr htab_vtab
;================================
; print_string
;================================
print_string:
ldy #0
print_string_loop:
lda (OUTL),Y
beq done_print_string
ora #$80
sta (BASL),Y
iny
bne print_string_loop
done_print_string:
rts
;====================
; point_to_end_string
;====================
point_to_end_string:
iny
tya
clc
adc OUTL
sta OUTL
lda #0
adc OUTH
sta OUTH
rts
;================================
; print_both_pages
;================================
print_both_pages:
lda DRAW_PAGE
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sta draw_page_smc+1
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lda #0
sta DRAW_PAGE
jsr move_and_print
lda #4
sta DRAW_PAGE
jsr move_and_print
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draw_page_smc:
lda #$d1
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sta DRAW_PAGE
rts ; oops forgot this initially
; explains the weird vertical stripes on the screen