can now store a single line of basic into memory
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@@ -6,6 +6,59 @@
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;; Then all we have to do is push the rest of the BASIC text up,
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;; and update the pointers in all following basic lines.
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basic_insert_line:
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;; ASSUMES basic_find_line has been called to set the insert point.
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;; We need to insert space for the link link token, the line number,
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;; and the zero-terminated line itself. This means 2+2+1 plus length
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;; of tokenised string after the line number
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;; But first, remember where the pointer will be, so that we can
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;; put the line in there after.
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lda basic_current_line_ptr+0
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pha
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lda basic_current_line_ptr+1
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pha
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;; Get number of bytes in tokenised line after line number
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lda tokenise_work2
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sec
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sbc tokenise_work1
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;; Add on the four bytes space we need
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clc
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adc #5
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tax
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;; Make the space
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jsr basic_shift_mem_up_and_relink
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;; Get pointer back
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pla
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sta basic_current_line_ptr+1
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pla
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sta basic_current_line_ptr+0
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inc $0427
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;; Write the line number
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ldy #2
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ldx #<basic_current_line_ptr
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lda basic_line_number+0
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jsr poke_under_roms
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iny
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lda basic_line_number+1
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jsr poke_under_roms
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;; Now store the line body itself
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line_store_loop:
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ldx tokenise_work1
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lda $0200,x
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inc tokenise_work1
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ldx #<basic_current_line_ptr
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iny
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jsr poke_under_roms
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lda tokenise_work1
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cmp tokenise_work2
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bne line_store_loop
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sec
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rts
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@@ -91,6 +91,16 @@ ml_bad_line_number:
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;; Got a valid line number.
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;; Skip any spaces after the line number
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ldx tokenise_work1
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skip_spaces:
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lda $0200,x
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cmp #$20
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bne +
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inx
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bne skip_spaces
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* stx tokenise_work1
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;; First, clear all variables, so that we only have to shove BASIC text around.
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;; (We could later remove this requirement, and the only effect should be
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;; to slow things down, and that you might have to either CLR if there is no
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@@ -30,31 +30,49 @@ basic_shift_mem_up_and_relink:
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;; To make life simple for the copy routine that lives in RAM,
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;; we have to adjust the end pointers down one page and set Y to the low
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;; byte of the copy size.
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tay
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dec memmove_src+1
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dec memmove_dst+1
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lda memmove_src+0
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sec
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sbc memmove_size+0
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sta memmove_src+0
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lda memmove_src+1
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sbc #0
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sta memmove_src+1
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lda memmove_dst+0
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sec
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sbc memmove_size+0
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sta memmove_dst+0
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lda memmove_dst+1
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sbc #0
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sta memmove_dst+1
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;; Now make exit easy, by being able to check for zero on size high byte when done
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inc memmove_size+1
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;; Then set Y to the number offset required
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ldy memmove_size+0
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;; Do the copy
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jsr shift_mem_up
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;; Now fix the pointer for the BASIC lines
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;; Now fix the pointer to the next line
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;; First, we need to point the current BASIC line
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;; pointer to the previously present lines
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stx tokenise_work3
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relink_up_next_line:
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ldx tokenise_work3
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lda tokenise_work3
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clc
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adc basic_current_line_ptr+0
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sta memmove_src+0
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lda basic_current_line_ptr+1
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adc #0
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sta memmove_src+1
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ldx #0
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ldy #<basic_current_line_ptr
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ldy #0
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ldx #<basic_current_line_ptr
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lda memmove_src+0
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jsr poke_under_roms
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inx
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iny
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lda memmove_src+1
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jsr poke_under_roms
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@@ -39,7 +39,6 @@ smu1:
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lda (memmove_src),y
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sta (memmove_dst),y
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dey
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cpy #$ff
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bne smu1
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dec memmove_src+1
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dec memmove_dst+1
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@@ -70,8 +69,10 @@ memmap_normal_routine:
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memmap_allram_routine:
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sei
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pha
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lda #$04
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sta $01
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pla
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rts
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ram_routines_end:
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