mirror of
https://github.com/stid/woz64.git
synced 2024-11-29 12:49:17 +00:00
801 lines
23 KiB
NASM
801 lines
23 KiB
NASM
BasicUpstart2(start)
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// c64
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.const bgcolor = $d020
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.const bordercolor = $d021
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.const screenram = $0400
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// kernel functions
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.const kBsout = $ab1e //kernel character output sub
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.const kChrout = $ffd2
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.const clearscreen = $e544
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// chars
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.const cr = 13
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// memory map
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.const kernel = $ff80
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.const start_basic = $0281
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.const end_basic = $0037
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.const step_size_garb = $000f
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.const dataset = $0090
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.const input_dev = 153
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.const out_dev = 154
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.const time_1 = 160
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.const time_2 = 161
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.const time_3 = 162
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.const ds_motor = 192
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// color petscii
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.const color_cyan = $9f
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.const color_light_blue = $9a
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.const color_green = $1e
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// local const
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.const pline_len = 40
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.const hex_open_chr = $5b
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.const hex_close_chr = $5d
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// zero page
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.const stringLow = $FB
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.const stirngHigh = $FC
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.const videoLow = $FD
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.const videoHigh = $FE
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.macro printHexByte(stringAddr, value) {
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lda #<stringAddr
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ldy #>stringAddr
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ldx value
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jsr printhex_row
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}
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.macro printHexWord(stringAddr, value) {
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bPrint(stringAddr)
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jsr popenhex
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lda value+1
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jsr printhex
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lda value
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jsr printhex
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jsr pclosehex
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bChar(cr)
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}
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.macro print(stringAddr) {
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lda #<stringAddr
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ldy #>stringAddr
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jsr bsout
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}
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.macro bPrint(stringAddr) {
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lda #<stringAddr
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ldy #>stringAddr
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jsr bsout
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}
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.macro bChar(char) {
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lda #char
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jsr kChrout
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}
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//==========================================================
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// code
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//==========================================================
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start:
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ldx #$00 // color
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stx $d021 // set background color
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stx $d020 // set border color
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lda #$04
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sta videoHigh
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lda #$00
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sta videoLow
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jsr clearscreen
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bChar(color_cyan)
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print(str_about)
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bChar(cr)
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bChar(color_light_blue)
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getKeyb:
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jsr Keyboard
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bcs NoValidInput
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stx TempX
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sty TempY
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cmp #$ff
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// Check A for Alphanumeric keys
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beq NoNewAphanumericKey
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// jsr printhex
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cmp #'m'
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beq mapMemory
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cmp #'q'
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beq exit
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jmp getKeyb
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NoNewAphanumericKey:
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// Check X & Y for Non-Alphanumeric Keys
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ldx TempX
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ldy TempY
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//stx $0401
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//sty $0402
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NoValidInput: // This may be substituted for an errorhandler if needed.
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jmp getKeyb
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exit: rts
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bsout:
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sty stirngHigh
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sta stringLow
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ldy #$00
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bloop: lda (stringLow), y
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cmp #0
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beq blexit
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sta (videoLow), y
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iny
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cpy #$f0
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bne bcontinue
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clc
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lda videoLow
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adc #$f0
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sta videoLow
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lda videoHigh
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adc #$00
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sta videoHigh
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bcontinue: jmp bloop
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blexit:
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rts
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mapMemory: {
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ldx #pline_len // lenht of pline
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jsr pline
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// ----------------------
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// ------ map table start
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// ----------------------
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// kernel
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printHexByte(str_row_kernel, kernel)
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// start basic area
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printHexWord(str_row_basic_start, start_basic)
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// end basic area
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printHexWord(str_row_basic_end, end_basic)
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// garbadge
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printHexByte(str_row_step_size_garb, printhex_row)
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// dataset
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printHexByte(str_row_dataset, dataset)
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// input dev
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printHexByte(str_row_input_dev, input_dev)
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// out dev
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printHexByte(str_row_out_dev, out_dev)
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// time 1
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printHexByte(str_row_time_1, time_1)
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// time 2
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printHexByte(str_row_time_2, time_2)
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// time 2
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printHexByte(str_row_time_2, time_3)
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// dataset motor
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printHexByte(str_row_ds_motor, ds_motor)
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// ----------------------
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// ------ map table end
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// ----------------------
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bChar(cr)
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ldx #pline_len
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jsr pline
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rts
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}
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// ————————————————————————————————————
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// popenhex
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// ————————————————————————————————————
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popenhex:
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bChar(hex_open_chr)
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bChar(color_green)
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rts
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// ————————————————————————————————————
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// pclosehex
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// ————————————————————————————————————
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pclosehex:
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bChar(color_light_blue)
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bChar(hex_close_chr)
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rts
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// ————————————————————————————————————
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// printhex_row
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// ————————————————————————————————————
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// ————————————————————————————————————
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// preparatory ops: .a: msn ascii char
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// .x: lsn ascii char
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// .y: value
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//
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// returned values: none
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// ————————————————————————————————————
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printhex_row:
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sta a_cache // preserve a
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txa // store x using a as it will be lost after ksout
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pha
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lda a_cache // get back a
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jsr bsout
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jsr popenhex
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pla // saved x back in a from saved a
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jsr printhex
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jsr pclosehex
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bChar(cr)
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rts
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// ————————————————————————————————————
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// printhex
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// ————————————————————————————————————
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// ————————————————————————————————————
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// preparatory ops: .a: byte to convert
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//
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// returned values: none
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// ————————————————————————————————————
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printhex:
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pha
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jsr binhex
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jsr kChrout
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txa
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jsr kChrout
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pla
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rts
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// ————————————————————————————————————
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// btohex
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// ————————————————————————————————————
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// ————————————————————————————————————
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// preparatory ops: .a: byte to convert
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//
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// returned values: .a: msn ascii char
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// .x: lsn ascii char
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// .y: entry value
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// ————————————————————————————————————
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binhex: pha //save byte
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and #%00001111 //extract lsn
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tax //save it
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pla //recover byte
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lsr //extract...
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lsr //msn
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lsr
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lsr
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pha //save msn
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txa //lsn
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jsr binhex1 //generate ascii lsn
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tax //save
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pla //get msn & fall thru
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//
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// convert nybble to hex ascii equivalent...
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binhex1: cmp #$0a
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bcc binhex2 //in decimal range
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adc #$66 //hex compensate
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binhex2: eor #%00110000 //finalize nybble
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rts //done
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// ————————————————————————————————————
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// pline
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// ————————————————————————————————————
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// ————————————————————————————————————
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// preparatory ops: .x: lenght
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// returned values: none
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// ————————————————————————————————————
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pline:
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cpx #0
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bne pline_start
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ldx #12 // default to 12 if 0 is passed in x
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pline_start: lda #102
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pline_loop: jsr kChrout
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dex
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cpx #0
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bne pline_loop
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lda #cr
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jsr kChrout
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rts
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.encoding "screencode_mixed"
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str_about:
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.text "c=64 mapper v2.0 by =stid="
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.byte 0
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str_row_kernel:
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.text " kernel "
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.byte 0
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str_row_basic_start:
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.text " start basic area "
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.byte 0
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str_row_basic_end:
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.text " end basic area "
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.byte 0
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str_row_step_size_garb:
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.text " step size garbage "
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.byte 0
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str_row_dataset:
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.text " dataset "
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.byte 0
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str_row_input_dev:
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.text " input device "
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.byte 0
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str_row_out_dev:
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.text " output device "
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.byte 0
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str_row_time_1:
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.text " time 1 "
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.byte 0
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str_row_time_2:
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.text " time 2 "
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.byte 0
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str_row_time_3:
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.text " time 3 "
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.byte 0
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str_row_ds_motor:
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.text " dataset motor "
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.byte 0
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str_row_generic:
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.text " hex value "
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.byte 0
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a_cache:
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.byte 0
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TempX:
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.byte 0
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TempY:
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.byte 0
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cursorX:
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.byte 0
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cursorY:
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.byte 0
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/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Keyboard IO Routine
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~~~~~~~~~~~~~~~~~~~
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By: TWW/CTR
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Preparatory Settings
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~~~~~~~~~~~~~~~~~~~~
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None
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Destroys
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~~~~~~~~
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Accumulator
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X-Register
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Y-Register
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Carry / Zero / Negative
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$dc00
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$dc01
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$50-$5f
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Footprint
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~~~~~~~~~
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#$206 Bytes
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Information
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~~~~~~~~~~~
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The routine uses "2 Key rollower" or up to 3 if the key-combination doesen't induce shadowing.
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If 2 or 3 keys are pressed simultaneously (within 1 scan) a "No Activity" state has to occur before new valid keys are returned.
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RESTORE is not detectable and must be handled by NMI IRQ.
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SHIFT LOCK is not detected due to unreliability.
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Usage
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~~~~~
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Example Code:
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jsr Keyboard
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bcs NoValidInput
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stx TempX
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sty TempY
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cmp #$ff
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beq NoNewAphanumericKey
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// Check A for Alphanumeric keys
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sta $0400
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NoNewAphanumericKey:
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// Check X & Y for Non-Alphanumeric Keys
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ldx TempX
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ldy TempY
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stx $0401
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sty $0402
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NoValidInput: // This may be substituted for an errorhandler if needed.
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Returned
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~~~~~~~~
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+=================================================+
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| Returned in Accumulator |
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+===========+===========+=============+===========+
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| $00 - @ | $10 - p | $20 - SPC | $30 - 0 |
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| $01 - a | $11 - q | $21 - | $31 - 1 |
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| $02 - b | $12 - r | $22 - | $32 - 2 |
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| $03 - c | $13 - s | $23 - | $33 - 3 |
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| $04 - d | $14 - t | $24 - | $34 - 4 |
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| $05 - e | $15 - u | $25 - | $35 - 5 |
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| $06 - f | $16 - v | $26 - | $36 - 6 |
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| $07 - g | $17 - w | $27 - | $37 - 7 |
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| $08 - h | $18 - x | $28 - | $38 - 8 |
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| $09 - i | $19 - y | $29 - | $39 - 9 |
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| $0a - j | $1a - z | $2a - * | $3a - : |
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| $0b - k | $1b - | $2b - + | $3b - ; |
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| $0c - l | $1c - £ | $2c - , | $3c - |
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| $0d - m | $1d - | $2d - - | $3d - = |
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| $0e - n | $1e - ^ | $2e - . | $3e - |
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| $0f - o | $1f - <- | $2f - / | $3f - |
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+-----------+-----------+-------------+-----------+
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+================================================================================
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| Return in X-Register |
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+=========+=========+=========+=========+=========+=========+=========+=========+
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| Bit 7 | Bit 6 | Bit 5 | Bit 4 | Bit 3 | Bit 2 | Bit 1 | Bit 0 |
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+---------+---------+---------+---------+---------+---------+---------+---------+
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| CRSR UD | F5 | F3 | F1 | F7 | CRSR RL | RETURN |INST/DEL |
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+---------+---------+---------+---------+---------+---------+---------+---------+
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+================================================================================
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| Return in Y-Register |
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+=========+=========+=========+=========+=========+=========+=========+=========+
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| Bit 7 | Bit 6 | Bit 5 | Bit 4 | Bit 3 | Bit 2 | Bit 1 | Bit 0 |
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+---------+---------+---------+---------+---------+---------+---------+---------+
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|RUN STOP | L-SHIFT | C= | R-SHIFT |CLR/HOME | CTRL | | |
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+---------+---------+---------+---------+---------+---------+---------+---------+
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CARRY:
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- Set = Error Condition (Check A for code):
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A = #$01 => No keyboard activity is detected.
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A = #$02 => Control Port #1 Activity is detected.
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A = #$03 => Key Shadowing / Ghosting is detected.
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A = #$04 => 2 or 3 new keys is detected within one scan
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A = #$05 => Awaiting "No Activity" state
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- Clear = Valid input
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A = #$ff => No new Alphanumeric Keys detected (some key(s) being held down AND/OR some Non-Alphanumeric key is causing valid return).
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A <> #$ff => New Alphanumeric Key returned. Non-Alphanumeric keys may also be returned in X or Y Register
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Issues/ToDo:
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~~~~~~~~~~~~
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- None
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Improvements:
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~~~~~~~~~~~~~
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- Replace the subroutine with a pseudocommand and account for speedcode parameter (Memory vs. Cycles).
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- Shorten the routine / Optimize if possible.
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History:
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~~~~~~~~
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V2.5 - New test tool.
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Added return of error codes.
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Fixed a bug causing Buffer Overflow.
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Fixed a bug in Non Alphanumerical Flags from 2.0.
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V2.1 - Shortened the source by adding .for loops & Updated the header and some comments.
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Added "simultaneous keypress" check.
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V2.0 - Added return of non-Alphanumeric keys into X & Y-Registers.
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Small optimizations here and there.
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V1.1 - Unrolled code to make it faster and optimized other parts of it.
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Removed SHIFT LOCK scanning.
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V1.0 - First Working Version along with test tool.
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
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* = * "Keyboard Scan Routine"
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// ZERO PAGE Varibles
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.const ScanResult = $50 // 8 bytes
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.const BufferNew = $58 // 3 bytes
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.const KeyQuantity = $5b // 1 byte
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.const NonAlphaFlagX = $5c // 1 byte
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.const NonAlphaFlagY = $5d // 1 byte
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.const TempZP = $5e // 1 byte
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.const SimultaneousKeys = $5f // 1 byte
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// Operational Variables
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.var MaxKeyRollover = 3
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Keyboard:
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{
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jmp Main
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//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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// Routine for Scanning a Matrix Row
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KeyInRow:
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asl
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bcs *+5
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jsr KeyFound
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.for (var i = 0 ; i < 7 ; i++) {
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inx
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asl
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bcs *+5
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jsr KeyFound
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}
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rts
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//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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// Routine for handling: Key Found
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KeyFound:
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stx TempZP
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dec KeyQuantity
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bmi OverFlow
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ldy KeyTable,x
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ldx KeyQuantity
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sty BufferNew,x
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ldx TempZP
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rts
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//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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// Routine for handling: Overflow
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OverFlow:
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pla // Dirty hack to handle 2 layers of JSR
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pla
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pla
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pla
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// Don't manipulate last legal buffer as the routine will fix itself once it gets valid input again.
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lda #$03
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sec
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rts
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//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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// Exit Routine for: No Activity
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NoActivityDetected:
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// Exit With A = #$01, Carry Set & Reset BufferOld.
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lda #$00
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sta SimultaneousAlphanumericKeysFlag // Clear the too many keys flag once a "no activity" state is detected.
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stx BufferOld
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stx BufferOld+1
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stx BufferOld+2
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sec
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lda #$01
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rts
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//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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// Exit Routine for Control Port Activity
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ControlPort:
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// Exit with A = #$02, Carry Set. Keep BufferOld to verify input after Control Port activity ceases
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sec
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lda #$02
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rts
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//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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// Configure Data Direction Registers
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Main:
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ldx #$ff
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stx $dc02 // Port A - Output
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ldy #$00
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sty $dc03 // Port B - Input
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//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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// Check for Port Activity
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sty $dc00 // Connect all Keyboard Rows
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cpx $dc01
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beq NoActivityDetected
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lda SimultaneousAlphanumericKeysFlag
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beq !+
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// Waiting for all keys to be released before accepting new input.
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lda #$05
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sec
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rts
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!:
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//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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// Check for Control Port #1 Activity
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stx $dc00 // Disconnect all Keyboard Rows
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cpx $dc01 // Only Control Port activity will be detected
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bne ControlPort
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//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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// Scan Keyboard Matrix
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lda #%11111110
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sta $dc00
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ldy $dc01
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sty ScanResult+7
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sec
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.for (var i = 6 ; i > -1 ; i--) {
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rol
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sta $dc00
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ldy $dc01
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sty ScanResult+i
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}
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//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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// Check for Control Port #1 Activity (again)
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|
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stx $dc00 // Disconnect all Keyboard Rows
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|
cpx $dc01 // Only Control Port activity will be detected
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|
bne ControlPort
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|
|
|
|
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//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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|
// Initialize Buffer, Flags and Max Keys
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|
|
|
// Reset current read buffer
|
|
stx BufferNew
|
|
stx BufferNew+1
|
|
stx BufferNew+2
|
|
|
|
// Reset Non-AlphaNumeric Flag
|
|
inx
|
|
stx NonAlphaFlagY
|
|
|
|
// Set max keys allowed before ignoring result
|
|
lda #MaxKeyRollover
|
|
sta KeyQuantity
|
|
|
|
// Counter to check for simultaneous alphanumeric key-presses
|
|
lda #$fe
|
|
sta SimultaneousKeys
|
|
|
|
|
|
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
// Check and flag Non Alphanumeric Keys
|
|
|
|
lda ScanResult+6
|
|
eor #$ff
|
|
and #%10000000 // Left Shift
|
|
lsr
|
|
sta NonAlphaFlagY
|
|
lda ScanResult+0
|
|
eor #$ff
|
|
and #%10100100 // RUN STOP - C= - CTRL
|
|
ora NonAlphaFlagY
|
|
sta NonAlphaFlagY
|
|
lda ScanResult+1
|
|
eor #$ff
|
|
and #%00011000 // Right SHIFT - CLR HOME
|
|
ora NonAlphaFlagY
|
|
sta NonAlphaFlagY
|
|
|
|
lda ScanResult+7 // The rest
|
|
eor #$ff
|
|
sta NonAlphaFlagX
|
|
|
|
|
|
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
// Check for pressed key(s)
|
|
|
|
lda ScanResult+7
|
|
cmp #$ff
|
|
beq *+5
|
|
jsr KeyInRow
|
|
.for (var i = 6 ; i > -1 ; i--) {
|
|
ldx #[7-i]*8
|
|
lda ScanResult+i
|
|
beq *+5
|
|
jsr KeyInRow
|
|
}
|
|
|
|
|
|
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
// Key Scan Completed
|
|
|
|
// Put any new key (not in old scan) into buffer
|
|
ldx #MaxKeyRollover-1
|
|
!: lda BufferNew,x
|
|
cmp #$ff
|
|
beq Exist // Handle 'null' values
|
|
cmp BufferOld
|
|
beq Exist
|
|
cmp BufferOld+1
|
|
beq Exist
|
|
cmp BufferOld+2
|
|
beq Exist
|
|
// New Key Detected
|
|
inc BufferQuantity
|
|
ldy BufferQuantity
|
|
sta Buffer,y
|
|
// Keep track of how many new Alphanumeric keys are detected
|
|
inc SimultaneousKeys
|
|
beq TooManyNewKeys
|
|
Exist:
|
|
dex
|
|
bpl !-
|
|
|
|
// Anything in Buffer?
|
|
ldy BufferQuantity
|
|
bmi BufferEmpty
|
|
// Yes: Then return it and tidy up the buffer
|
|
dec BufferQuantity
|
|
lda Buffer
|
|
ldx Buffer+1
|
|
stx Buffer
|
|
ldx Buffer+2
|
|
stx Buffer+1
|
|
jmp Return
|
|
|
|
BufferEmpty: // No new Alphanumeric keys to handle.
|
|
lda #$ff
|
|
|
|
Return: // A is preset
|
|
clc
|
|
// Copy BufferNew to BufferOld
|
|
ldx BufferNew
|
|
stx BufferOld
|
|
ldx BufferNew+1
|
|
stx BufferOld+1
|
|
ldx BufferNew+2
|
|
stx BufferOld+2
|
|
// Handle Non Alphanumeric Keys
|
|
ldx NonAlphaFlagX
|
|
ldy NonAlphaFlagY
|
|
rts
|
|
|
|
TooManyNewKeys:
|
|
sec
|
|
lda #$ff
|
|
sta BufferQuantity
|
|
sta SimultaneousAlphanumericKeysFlag
|
|
lda #$04
|
|
rts
|
|
|
|
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
KeyTable:
|
|
.byte $ff, $ff, $ff, $ff, $ff, $ff, $ff, $ff // CRSR DOWN, F5, F3, F1, F7, CRSR RIGHT, RETURN, INST DEL
|
|
.byte $ff, $05, $13, $1a, $34, $01, $17, $33 // LEFT SHIFT, "E", "S", "Z", "4", "A", "W", "3"
|
|
.byte $18, $14, $06, $03, $36, $04, $12, $35 // "X", "T", "F", "C", "6", "D", "R", "5"
|
|
.byte $16, $15, $08, $02, $38, $07, $19, $37 // "V", "U", "H", "B", "8", "G", "Y", "7"
|
|
.byte $0e, $0f, $0b, $0d, $30, $0a, $09, $39 // "N", "O" (Oscar), "K", "M", "0" (Zero), "J", "I", "9"
|
|
.byte $2c, $00, $3a, $2e, $2d, $0c, $10, $2b // ",", "@", ":", ".", "-", "L", "P", "+"
|
|
.byte $2f, $1e, $3d, $ff, $ff, $3b, $2a, $1c // "/", "^", "=", RIGHT SHIFT, HOME, ";", "*", "£"
|
|
.byte $ff, $11, $ff, $20, $32, $ff, $1f, $31 // RUN STOP, "Q", "C=" (CMD), " " (SPC), "2", "CTRL", "<-", "1"
|
|
|
|
BufferOld:
|
|
.byte $ff, $ff, $ff
|
|
|
|
Buffer:
|
|
.byte $ff, $ff, $ff, $ff
|
|
|
|
BufferQuantity:
|
|
.byte $ff
|
|
|
|
SimultaneousAlphanumericKeysFlag:
|
|
.byte $00
|
|
} |