reached target granularity in screen code
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FeralChild64 committed
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@@ -113,7 +113,7 @@ read_from_keyboard:
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sta LXSP+1
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// Calculate length
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jsr get_current_line_logical_length
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jsr screen_get_current_line_logical_length
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tay
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iny
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!: dey
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@@ -1,295 +0,0 @@
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//
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// CHROUT routine - screen support
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//
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chrout_screen:
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// Crude implementation of character output
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sei // XXX why do we need to disable interrupts?
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jsr cursor_hide_if_visible
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lda SCHAR
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tax
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// All the PETSCII control codes are within $0x, $1x, $8x, $9x, remaining
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// ones are always printable characters; separate away control codes
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and #$60
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bne !+
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jmp chrout_screen_control
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!:
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txa
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// Literals - first convert PETSCII to screen code
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// Codes $C0-$DF become $40-$5F
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cmp #$E0
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bcs !+
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cmp #$C0
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bcc !+
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and #$7F
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jmp output_literal_char // not high char
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!:
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// Range $20-$3F is unchanged
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cmp #$40
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bcc output_literal_char // not high char
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// Unshifted letters and symbols from $40-$5F
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// all end up being -$40
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// (C64 PRG p376)
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// But anything >= $80 needs to be -$40
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// (C64 PRG p380-381)
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// And bit 7 should be cleared, only to be
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// set by reverse video
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sec
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sbc #$40
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// Fix shifted chars by adding $20 again
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cmp #$20
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bcc output_literal_char // not high char
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cmp #$40
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bcs output_literal_char // not high char
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clc
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adc #$20
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output_literal_char:
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// Write normal character on the screen
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pha
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ldy PNTR
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ora RVS // Compute's Mapping the 64 p38
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sta (PNT),y
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// Decrement number of chars waiting to be inserted
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lda INSRT
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beq !+
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dec INSRT
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!:
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pla
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cmp #$22
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bne not_quote
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// Toggle quote flag if required
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lda QTSW
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eor #$80
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sta QTSW
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not_quote:
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// Set colour
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lda COLOR
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sta (USER),y
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// Advance the column, and scroll screen down if we need
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// to insert a 2nd line in this logical line.
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// (eg Compute's Mapping the 64 p41)
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ldx TBLX
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iny
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sty PNTR
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cpy #40
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bne !+
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jsr screen_grow_logical_line
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ldy PNTR
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!:
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cpy #80
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bcc no_screen_advance_to_next_line
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lda #0
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sta PNTR
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jmp screen_advance_to_next_line
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no_screen_advance_to_next_line:
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jmp chrout_done
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not_last_line:
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rts
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scroll_up_if_on_last_line:
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// Colour RAM is always in fixed place, so is easiest
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// to use to check if we are on the last line.
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// The last line is at $D800 + 24*40 = $DBC0
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lda USER+1
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cmp #>$DBC0
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bne not_last_line
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lda USER+0
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cmp #<$DBC0
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beq is_last_line
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jsr get_current_line_logical_length
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clc
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adc USER+0
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cmp #<$DBE7-1
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bcc not_last_line
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is_last_line:
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dec TBLX
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// FALL THROUGH
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scroll_screen_up:
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// Now scroll the whole screen up either one or two lines
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// based on whether the first screen line is linked or not.
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// Get pointers to start of screen + colour RAM
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lda HIBASE
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sta PNT+1
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sta SAL+1
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lda #>$D800
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sta USER+1
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sta EAL+1
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lda #$00
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sta PNT+0
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sta USER+0
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// Get pointers to screen/colour RAM source
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lda LDTBL+0
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bmi !+
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lda #40
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.byte $2C // BIT $nnnn to skip next instruction
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!:
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lda #80
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sta SAL+0
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sta EAL+0
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// Copy first three pages
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ldy #$00
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ldx #3
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scroll_copy_loop:
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lda (EAL),y
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sta (USER),y
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lda (SAL),y
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sta (PNT),y
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iny
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bne scroll_copy_loop
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inc SAL+1
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inc PNT+1
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inc EAL+1
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inc USER+1
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dex
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bne scroll_copy_loop
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// Copy last partial page
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// We need to copy 1000-(3*256)-line length
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// = 232 - line length
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lda SAL+0
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lda #232
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sec
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sbc SAL+0
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tax
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scroll_copy_loop2:
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lda (EAL),y
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sta (USER),y
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lda (SAL),y
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sta (PNT),y
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iny
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dex
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bne scroll_copy_loop2
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// Fill in scrolled up area
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ldx SAL+0
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scroll_copy_loop3:
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lda COLOR
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sta (USER),y
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lda #$20
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sta (PNT),y
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iny
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dex
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bne scroll_copy_loop3
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// Shift line linkage list
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ldy #0
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ldx #24
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link_copy:
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lda LDTBL+1,y
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sta LDTBL+0,y
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iny
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dex
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bne link_copy
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// Clear line link flag of last line
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stx LDTBL+24
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// Restore correct line pointers
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jsr calculate_screen_line_pointer
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rts
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get_current_line_logical_length:
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ldy TBLX
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lda LDTBL,y
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bpl line_not_linked_del
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lda #79
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.byte $2c // BIT absolute mode, which we use to skip the next two instruction bytes
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line_not_linked_del:
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lda #39
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sta LNMX
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rts
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screen_advance_to_next_line:
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// jsr cursor_hide_if_visible
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// Go to start of line
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lda #0
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sta PNTR
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// Advance line number
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ldy TBLX
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// Do quick fix to line pointer to work out if it is off
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// the bottom of the screen.
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ldx #40
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lda LDTBL,y
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bmi !+
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.byte $2c
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!: ldx #80
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txa
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clc
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adc PNT+0
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sta PNT+0
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lda PNT+1
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adc #0
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sta PNT+1
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inc TBLX
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// Check if it will trigger scrolling
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// Work out if we have gone off the bottom of the screen?
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// 1040 > 1024, so if high byte of screen pointer is >= (HIBASE+4),
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// then we are off the bottom of the screen
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lda PNT+1
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sec
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sbc HIBASE
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cmp #3
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bcc !+
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lda PNT+0
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cmp #$e7
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bcc !+
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// Off the bottom of the screen
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jsr scroll_screen_up
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!:
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jsr calculate_screen_line_pointer
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jmp chrout_done
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@@ -20,7 +20,7 @@ plot_set:
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sty PNTR
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stx TBLX
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jsr calculate_screen_line_pointer
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jsr screen_calculate_line_pointer
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// XXX cursor blink might need to be handled too
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@@ -16,10 +16,17 @@ CHROUT:
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// (Confirmed by writing a test program that X and Y
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// don't get modified, in agreement with C64 PRG's
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// description of CHROUT)
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#if CONFIG_CPU_MOS_6502
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txa
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pha
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tya
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pha
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#else
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phx
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phy
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#endif
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php
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// Determine the device number
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@@ -46,10 +53,17 @@ chrout_done_fail:
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plp
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// Restore X and Y
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#if CONFIG_CPU_MOS_6502
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pla
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tay
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pla
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tax
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#else
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ply
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plx
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#endif
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sec // indicate failure
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rts
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@@ -59,10 +73,16 @@ chrout_done_unknown_device:
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plp
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// Restore X and Y
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#if CONFIG_CPU_MOS_6502
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pla
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tay
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pla
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tax
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#else
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ply
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plx
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#endif
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// End wioth error
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jmp lvs_device_not_found_error
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@@ -73,10 +93,17 @@ chrout_done:
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plp
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// Restore X and Y
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#if CONFIG_CPU_MOS_6502
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pla
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tay
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pla
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tax
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#else
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ply
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plx
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#endif
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lda SCHAR
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clc // indicate success
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rts
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@@ -0,0 +1,108 @@
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//
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// CHROUT routine - screen support (character output)
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//
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chrout_screen:
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sei // XXX why do we need to disable interrupts?
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jsr cursor_hide_if_visible
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lda SCHAR
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tax
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// All the PETSCII control codes are within $0x, $1x, $8x, $9x, remaining
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// ones are always printable characters; separate away control codes
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and #$60
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bne !+
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jmp chrout_screen_control
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!:
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txa
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// Literals - first convert PETSCII to screen code
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// Codes $C0-$DF become $40-$5F
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cmp #$E0
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bcs !+
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cmp #$C0
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bcc !+
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and #$7F
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jmp output_literal_char // not high char
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!:
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// Range $20-$3F is unchanged
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cmp #$40
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bcc output_literal_char // not high char
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// Unshifted letters and symbols from $40-$5F
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// all end up being -$40
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// (C64 PRG p376)
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// But anything >= $80 needs to be -$40
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// (C64 PRG p380-381)
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// And bit 7 should be cleared, only to be
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// set by reverse video
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sec
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sbc #$40
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// Fix shifted chars by adding $20 again
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cmp #$20
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bcc output_literal_char // not high char
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cmp #$40
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bcs output_literal_char // not high char
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clc
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adc #$20
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output_literal_char:
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// Write normal character on the screen
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pha
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ldy PNTR
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ora RVS // Compute's Mapping the 64 p38
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sta (PNT),y
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// Decrement number of chars waiting to be inserted
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lda INSRT
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beq !+
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dec INSRT
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!:
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pla
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cmp #$22
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bne not_quote
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// Toggle quote flag if required
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lda QTSW
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eor #$80
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sta QTSW
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not_quote:
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// Set colour
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lda COLOR
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sta (USER),y
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// Advance the column, and scroll screen down if we need
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// to insert a 2nd line in this logical line.
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// (eg Compute's Mapping the 64 p41)
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ldx TBLX
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iny
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sty PNTR
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cpy #40
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bne !+
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jsr screen_grow_logical_line
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ldy PNTR
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!:
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cpy #80
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bcc no_screen_advance_to_next_line
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lda #0
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sta PNTR
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jmp screen_advance_to_next_line
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no_screen_advance_to_next_line:
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jmp chrout_done
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@@ -49,7 +49,7 @@ chrout_try_CRSR_UP:
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sec
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sbc #40
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sta PNTR
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jsr calculate_screen_line_pointer
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jsr screen_calculate_line_pointer
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jmp chrout_done
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!:
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chrout_try_CRSR_DOWN:
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@@ -65,8 +65,8 @@ chrout_try_CRSR_DOWN:
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// now will break things. The pointer update is required
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// so that we can tell if we really are on the bottom phys
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// screen line or not
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jsr scroll_up_if_on_last_line
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jsr calculate_screen_line_pointer
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jsr screen_scroll_up_if_on_last_line
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jsr screen_calculate_line_pointer
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jmp chrout_done
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!:
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chrout_try_CRSR_LEFT:
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@@ -86,7 +86,7 @@ chrout_try_CRSR_RIGHT:
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bne !+
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inc PNTR
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jsr calculate_screen_line_pointer
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jsr screen_calculate_line_pointer
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jmp chrout_done
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!:
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chrout_try_RVS_ON:
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@@ -202,5 +202,5 @@ chrout_screen_control_done: // unknown, LF, or no more actions required // XXX
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chrout_screen_control_calcptr_done: // XXX to !csc_calcptr_done
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jsr calculate_screen_line_pointer
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jsr screen_calculate_line_pointer
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jmp chrout_done
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@@ -24,7 +24,7 @@ chrout_screen_del_column_0:
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// previous line, without actually deleting anything
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dec TBLX
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jsr get_current_line_logical_length
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jsr screen_get_current_line_logical_length
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lda LNMX
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sta PNTR
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@@ -33,7 +33,7 @@ chrout_screen_del_column_0:
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chrout_screen_del_column_non_0:
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// Copy rest of line down
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jsr get_current_line_logical_length
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jsr screen_get_current_line_logical_length
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ldy PNTR
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cpy LNMX
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beq !++
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@@ -52,7 +52,7 @@ chrout_screen_del_column_non_0:
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bne !-
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// Clear char at end of line
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jsr get_current_line_logical_length
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jsr screen_get_current_line_logical_length
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tay
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lda #$20
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sta (PNT),y
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@@ -8,7 +8,7 @@ chrout_screen_ins:
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// Insert (shift-DELETE)
|
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|
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// Abort if line already max length, ie 79th char is not a space
|
||||
jsr get_current_line_logical_length
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||||
jsr screen_get_current_line_logical_length
|
||||
cmp #79
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||||
bne !+
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||||
tay
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@@ -30,7 +30,7 @@ chrout_screen_ins:
|
||||
|
||||
!:
|
||||
// Shuffle chars towards end of line
|
||||
jsr get_current_line_logical_length
|
||||
jsr screen_get_current_line_logical_length
|
||||
tay
|
||||
!:
|
||||
// Note: While the following routine is obvious to any skilled
|
||||
|
||||
@@ -28,7 +28,7 @@ cursor_blink:
|
||||
// FALLTROUGH
|
||||
|
||||
cursor_draw:
|
||||
jsr calculate_screen_line_pointer // XXX make sure this is not needed and remove the call
|
||||
jsr screen_calculate_line_pointer // XXX make sure this is not needed and remove the call
|
||||
|
||||
ldy PNTR
|
||||
lda (PNT),y
|
||||
|
||||
@@ -9,4 +9,4 @@ cursor_home:
|
||||
sta PNTR // x position
|
||||
sta TBLX // y position
|
||||
|
||||
jmp set_pointer_to_current_screen_line
|
||||
jmp screen_set_pointer_to_current_line
|
||||
@@ -0,0 +1,47 @@
|
||||
|
||||
screen_advance_to_next_line:
|
||||
|
||||
// jsr cursor_hide_if_visible
|
||||
|
||||
// Go to start of line
|
||||
lda #0
|
||||
sta PNTR
|
||||
// Advance line number
|
||||
ldy TBLX
|
||||
|
||||
// Do quick fix to line pointer to work out if it is off
|
||||
// the bottom of the screen.
|
||||
ldx #40
|
||||
lda LDTBL,y
|
||||
bmi !+
|
||||
.byte $2c
|
||||
!: ldx #80
|
||||
txa
|
||||
clc
|
||||
adc PNT+0
|
||||
sta PNT+0
|
||||
lda PNT+1
|
||||
adc #0
|
||||
sta PNT+1
|
||||
|
||||
inc TBLX
|
||||
|
||||
// Check if it will trigger scrolling
|
||||
// Work out if we have gone off the bottom of the screen?
|
||||
// 1040 > 1024, so if high byte of screen pointer is >= (HIBASE+4),
|
||||
// then we are off the bottom of the screen
|
||||
lda PNT+1
|
||||
sec
|
||||
sbc HIBASE
|
||||
cmp #3
|
||||
bcc !+
|
||||
lda PNT+0
|
||||
cmp #$e7
|
||||
bcc !+
|
||||
|
||||
// Off the bottom of the screen
|
||||
jsr scroll_screen_up
|
||||
!:
|
||||
|
||||
jsr screen_calculate_line_pointer
|
||||
jmp chrout_done
|
||||
@@ -1,5 +1,5 @@
|
||||
|
||||
calculate_screen_line_pointer: // XXX rename to screen_calculate_line_pointer
|
||||
screen_calculate_line_pointer:
|
||||
jsr screen_normalize_xy
|
||||
|
||||
// Reset pointer to start of screen
|
||||
@@ -21,9 +21,9 @@ calculate_screen_line_pointer: // XXX rename to screen_calculate_line_pointer
|
||||
// -1 offset is because we count down from N to 1, not
|
||||
// N-1 to 0.
|
||||
lda LDTBL-1,x
|
||||
bpl cslp_l1
|
||||
bpl sclp_l1
|
||||
ldy #80
|
||||
cslp_l1:
|
||||
sclp_l1:
|
||||
// Add computed line length to pointer value
|
||||
tya
|
||||
clc
|
||||
|
||||
@@ -0,0 +1,11 @@
|
||||
|
||||
screen_get_current_line_logical_length:
|
||||
ldy TBLX
|
||||
lda LDTBL,y
|
||||
bpl !+
|
||||
lda #79
|
||||
.byte $2c // BIT absolute mode, which we use to skip the next two instruction bytes
|
||||
!:
|
||||
lda #39
|
||||
sta LNMX
|
||||
rts
|
||||
@@ -12,7 +12,7 @@ screen_grow_logical_line:
|
||||
// Now make space for the extra line added.
|
||||
// If we are on the last physical line of the screen,
|
||||
// Then we need to scroll the screen up
|
||||
jsr scroll_up_if_on_last_line
|
||||
jsr screen_scroll_up_if_on_last_line
|
||||
|
||||
// Scroll screen down to make space
|
||||
// As we are scrolling down, we start from the end,
|
||||
@@ -106,7 +106,7 @@ cl_inner:
|
||||
bne copy_line_down_loop
|
||||
|
||||
no_copy_down:
|
||||
jsr calculate_screen_line_pointer
|
||||
jsr screen_calculate_line_pointer
|
||||
|
||||
// Erase newly inserted line
|
||||
ldy #79
|
||||
|
||||
@@ -0,0 +1,115 @@
|
||||
|
||||
not_last_line:
|
||||
rts
|
||||
|
||||
screen_scroll_up_if_on_last_line:
|
||||
|
||||
// Colour RAM is always in fixed place, so is easiest
|
||||
// to use to check if we are on the last line.
|
||||
// The last line is at $D800 + 24*40 = $DBC0
|
||||
lda USER+1
|
||||
cmp #>$DBC0
|
||||
bne not_last_line
|
||||
|
||||
lda USER+0
|
||||
cmp #<$DBC0
|
||||
beq is_last_line
|
||||
|
||||
jsr screen_get_current_line_logical_length
|
||||
clc
|
||||
adc USER+0
|
||||
cmp #<$DBE7-1
|
||||
bcc not_last_line
|
||||
|
||||
is_last_line:
|
||||
|
||||
dec TBLX
|
||||
|
||||
// FALLTHROUGH
|
||||
|
||||
scroll_screen_up:
|
||||
// Now scroll the whole screen up either one or two lines
|
||||
// based on whether the first screen line is linked or not.
|
||||
|
||||
// Get pointers to start of screen + colour RAM
|
||||
lda HIBASE
|
||||
sta PNT+1
|
||||
sta SAL+1
|
||||
lda #>$D800
|
||||
sta USER+1
|
||||
sta EAL+1
|
||||
lda #$00
|
||||
sta PNT+0
|
||||
sta USER+0
|
||||
|
||||
// Get pointers to screen/colour RAM source
|
||||
lda LDTBL+0
|
||||
bmi !+
|
||||
lda #40
|
||||
.byte $2C // BIT $nnnn to skip next instruction
|
||||
!:
|
||||
lda #80
|
||||
sta SAL+0
|
||||
sta EAL+0
|
||||
|
||||
// Copy first three pages
|
||||
ldy #$00
|
||||
ldx #3
|
||||
scroll_copy_loop:
|
||||
lda (EAL),y
|
||||
sta (USER),y
|
||||
lda (SAL),y
|
||||
sta (PNT),y
|
||||
|
||||
iny
|
||||
bne scroll_copy_loop
|
||||
|
||||
inc SAL+1
|
||||
inc PNT+1
|
||||
inc EAL+1
|
||||
inc USER+1
|
||||
dex
|
||||
bne scroll_copy_loop
|
||||
|
||||
// Copy last partial page
|
||||
// We need to copy 1000-(3*256)-line length
|
||||
// = 232 - line length
|
||||
lda SAL+0
|
||||
lda #232
|
||||
sec
|
||||
sbc SAL+0
|
||||
tax
|
||||
scroll_copy_loop2:
|
||||
lda (EAL),y
|
||||
sta (USER),y
|
||||
lda (SAL),y
|
||||
sta (PNT),y
|
||||
iny
|
||||
dex
|
||||
bne scroll_copy_loop2
|
||||
|
||||
// Fill in scrolled up area
|
||||
ldx SAL+0
|
||||
scroll_copy_loop3:
|
||||
lda COLOR
|
||||
sta (USER),y
|
||||
lda #$20
|
||||
sta (PNT),y
|
||||
iny
|
||||
dex
|
||||
bne scroll_copy_loop3
|
||||
|
||||
// Shift line linkage list
|
||||
ldy #0
|
||||
ldx #24
|
||||
link_copy:
|
||||
lda LDTBL+1,y
|
||||
sta LDTBL+0,y
|
||||
iny
|
||||
dex
|
||||
bne link_copy
|
||||
// Clear line link flag of last line
|
||||
stx LDTBL+24
|
||||
|
||||
// Restore correct line pointers
|
||||
jmp screen_calculate_line_pointer
|
||||
+6
-5
@@ -2,7 +2,8 @@
|
||||
// into the pointer at $D1 (PNT).
|
||||
// It must take into account the screen line link table
|
||||
// (Compute's Mapping the 64 p216)
|
||||
set_pointer_to_current_screen_line:
|
||||
|
||||
screen_set_pointer_to_current_line:
|
||||
// Get pointer to start of the screen
|
||||
lda HIBASE
|
||||
sta PNT+1
|
||||
@@ -12,15 +13,15 @@ set_pointer_to_current_screen_line:
|
||||
// Now advance for the number of lines
|
||||
ldx TBLX
|
||||
|
||||
sptcsl_l2:
|
||||
sptcl_l2:
|
||||
// XXX - Should we read the columns per line from
|
||||
// somewhere?
|
||||
ldy #<40
|
||||
// Double line length if line is linked
|
||||
lda LDTBL,x
|
||||
bpl sptcsl_l1
|
||||
bpl sptcl_l1
|
||||
ldy #<80
|
||||
sptcsl_l1:
|
||||
sptcl_l1:
|
||||
tya
|
||||
clc
|
||||
adc PNT+0
|
||||
@@ -29,6 +30,6 @@ sptcsl_l1:
|
||||
sta PNT+1
|
||||
|
||||
dex
|
||||
bpl sptcsl_l2
|
||||
bpl sptcl_l2
|
||||
|
||||
rts
|
||||
Reference in new issue
Block a user