6502-OS/spicode.s65

.include "system.h65"
.include "string.h65"
.include "lcd.h65"
.include "math.h65"
.include "keypad.h65"
.include "keyboard_handler.h65"
.include "chars.h65"
.include "parity.h65"
.include "sleep.h65"
.import homeloop:absolute
.import home:absolute

.segment "SPI"
.export CODE_START

.import memcopy



CODE_START:
.assert * = $5000, error, "SPI Code not at $5000"
    jsr lcd::clear
    lda #'$'
    jsr lcd::print_char
    ; jmp homeloop
    DEBUG_LED_OFF 0
    DEBUG_LED_OFF 1
    DEBUG_LED_OFF 2

    StoreDByte _process_cmd_answer, $3200


    jsr ps2kb::init
    stz kb::status
    StoreDByte process_scancode,ps2kb::scancode_handler
    ; jsr ps2kb::begin_receive
    JsrIndirect @a1, @a2
    stp
    stp
    stp
    stp
    stp
@a1:
    lda #'1'
    jsr lcd::print_char
    rts
    stp
    stp
    stp
    stp
@a2:
    lda #'2'
    jsr lcd::print_char

    lda #'%'
    jsr lcd::print_char

    stz kp::_DEBUG_VAL
    ldy #0
@loop:
    wai
    lda ps2kb::scancode
    beq @noscancode
    jsr process_scancode
    stz ps2kb::scancode
    lda char
    beq @onlykeycode
    Strf fmt_codechar,out_str,keycode,kb::status,char
    PrintNC out_str
    stz char
    stz keycode
    bra @noscancode
@onlykeycode:
    lda keycode
    beq @noscancode
    Strf fmt_code,out_str,keycode,keycode_flags
    PrintNC out_str
    stz keycode
@noscancode:
    bbr5 kb::status, @shift_off
@shift_on:
    ; DEBUG_LED_ON 0
    bra @check_caps
@shift_off:
    ; DEBUG_LED_OFF 0
@check_caps:
    bbr4 kb::status, @caps_off
@caps_on:
    ; DEBUG_LED_ON 2
    bra @read_keypad
@caps_off:
    ; DEBUG_LED_OFF 2
@read_keypad:
    lda kp::_DEBUG_VAL
    jeq @loop
    stz kp::_DEBUG_VAL
    cmp #'*'
    jeq homeloop
    cmp #'1'
    beq @l1
    cmp #'2'
    beq @l2
    cmp #'3'
    beq @l3
    cmp #'A'
    beq @lA
    cmp #'B'
    beq @lB
    cmp #'C'
    beq @lC
    cmp #'D'
    beq @lD
    jsr lcd::print_char
    jmp @loop
@l1:
    ; jsr irq_on_shift_reg
    jsr $3000
    lda #'*'
    jsr lcd::print_char
    jmp @loop
@l2:
    ; jsr irq_on_timer
    jsr $3100
    lda #'#'
    jsr lcd::print_char
    jmp @loop
@l3:
    lda $3000,y
    jsr lcd::print_char
    iny
    jmp @loop
@lA:
    jsr ps2kb::begin_receive
    ; StoreDByte _receive_irq_timer_handler, $3100
    jmp @loop
@lB:
    ; Printf "kc%x;", out_str, kb::scancode
    jsr lcd::clear
    ldx out_idx
    lda #0
    sta out_str,x
    Print out_str
    stz out_idx

    jmp @loop
@lC:
    jsr lcd::clear
    jmp @loop
@lD:
    lda ps2kb::STATUS::SEND_CMD
    sta ps2kb::status
    ; lda #$ed
    ; ldx #%00000111
    ; lda #$f6
    ; lda #$ff
    lda #$ee
    ; ldx #$ee
    ; ldx #0
    ldx #ps2kb::NO_DATA
    sta ps2kb::send_cmd
    stx ps2kb::send_data
    jsr _send_byte
    ; jsr ps2kb::send_command;
    jmp @loop

.byte '@'

.proc process_scancode
    ; DEBUG_LED_OFF 1
    ; check how this scancode needs to be interpreted
    ldx ps2kb::scancode
    bit kb::status
    jmi release_key   ; bit 7 set
    bvs @twobytecode  ; bit 6 set
    ; DEBUG_LED_ON 1

    ; check mods
    cpx #kb::K_RELEASE
    beq @code_release
    cpx #kb::K::LEFTSHIFT
    beq @code_shift
    cpx #kb::K::RIGHTSHIFT
    beq @code_shift
    cpx #kb::K_TWOBYTE
    beq @code_twobytecode
    cpx #kb::K::CAPSLOCK
    beq @code_capslock

    ; a real keycode and not a released keycode, twobyte or release scancode
    stz keycode_flags
    stx keycode
    cmp #$62  ; $61 is the largest ascii scancode
    bcs @special
    bbs5 kb::status,@modshift   ; if shift active
@nomod:
    lda kb::CHARS_NOMOD,x 
    beq @special
@char:  ; order which is fastet most of the time (lowercase characters)
    sta char
    rts
@modshift:
    lda kb::CHARS_MODSHIFT,x 
    bne @char
@special:
    rts
    
@code_release:      ; set release
    smb7 kb::status 
    rts
@code_twobytecode:  ; set twobytecode
    smb6 kb::status
    rts
@code_shift:        ; process shift
    bbs4 kb::status, @unset_shift  ; unset shift when capslock is on
@set_shift:
    smb5 kb::status
    rts
@unset_shift:
    rmb5 kb::status
    rts
@code_capslock:     ; toggle capslock & shift
    bbs1 kb::status, @rts   ; ignore if held
    lda kb::status
    ora #(kb::STATUS::CAPSLOCK_HELD)
    ; toggle and capslock shift
    eor #(kb::STATUS::CAPSLOCK | kb::STATUS::SHIFT)
    sta kb::status
    rts
@code_rightalt:     ; set rightalt
    smb3 kb::status
    rts
@code_numlock:      ; set numlock
    smb2 kb::status
    rts

@twobytecode:
    rmb6 kb::status  ; unset twobytecode
    ; check mods
    cpx #kb::K2::RIGHTALT
    beq @code_rightalt

    lda #kb::STATUS::TWOBYTE
    sta keycode_flags
    stx keycode
@rts:
    rts
.endproc

;; @param S: The status register must be set through `bit kb::status`
;; @param X: The scancode
.proc release_key
    bvs @twobytecode
    rmb7 kb::status 

    ; check mods
    cpx #kb::K_TWOBYTE
    beq @code_twobytecode
    cpx #kb::K::LEFTSHIFT
    beq @code_shift
    cpx #kb::K::RIGHTSHIFT
    beq @code_shift
    cpx #kb::K::CAPSLOCK
    beq @code_capslock
    ; no need to process capslock - it gets toggled when pressed
    rts
@code_twobytecode:  ; unset special
    rmb6 kb::status
    rts
@code_shift:        ; process shift
    bbs4 kb::status, @code_shift_caps  ; set shift when capslock is on
    rmb5 kb::status ; unset if capslock is off
    rts
@code_shift_caps:
    smb5 kb::status
    rts
@code_capslock:     ; unset CAPSLOCK_HELD
    rmb1 kb::status
    rts
@code_rightalt:     ; unset rightalt
    rmb3 kb::status
    rts
@code_numlock:      ; unset numlock
    rmb2 kb::status
    rts

@twobytecode:
    rmb6 kb::status  ; unset twobytecode
    ; check mods
    cpx #kb::K2::RIGHTALT
    beq @code_rightalt
    rts
.endproc

;;********************************************************************************
;; @macro Enable the clock signal from the keyboard
;; @modifies: A
;; @details
;;  Stop pulling the keyboards clock low
;;********************************************************************************
.macro _EnableClock
    ; set pin to input
    lda ps2kb::VIA + ps2kb::PULL_DDR
    and #<~ps2kb::PULL_MASK_CLK
    sta ps2kb::VIA + ps2kb::PULL_DDR
.endmacro

;;********************************************************************************
;; @macro Disable the clock signal from the keyboard
;; @modifies: A
;; @details
;;  Pulls the keyboards clock low
;;********************************************************************************
.macro _DisableClock
    ; set pin to output
    lda ps2kb::VIA + ps2kb::PULL_DDR
    ora #ps2kb::PULL_MASK_CLK
    sta ps2kb::VIA + ps2kb::PULL_DDR
    ; set pin low
    lda ps2kb::VIA + ps2kb::PULL_REG
    and #<~ps2kb::PULL_MASK_CLK
    sta ps2kb::VIA + ps2kb::PULL_REG
.endmacro


.proc _send_byte
    pha
        IO_DisableIRQ ps2kb::VIA, (IO::IRQ::T2 | IO::IRQ::SR)

        _DisableClock

        lda #'X'
        jsr lcd::print_char

        ; set shift register to output
        lda ps2kb::VIA + IO::ACR
        and #<~IO::ACR_MASK::SR
        ora #IO::ACR::SR_SOUT_PHIE
        sta ps2kb::VIA + IO::ACR
        stz ps2kb::VIA + IO::SR
        ; shift out the startbit = data low
        _EnableClock    
        _DisableClock
        ; reset shift register to start the count at 0 again
        lda #IO::ACR::SR_SOUT_PHIE
        trb ps2kb::VIA + IO::ACR
        tsb ps2kb::VIA + IO::ACR

        ; setup the low timer byte
        lda #<ps2kb::TIMER_SEND
        sta ps2kb::VIA + IO::T2CL

        ; setup interrupt handlers
        StoreDByte ps2kb::_send_irq_shift_reg_handler, $3000
        ; StoreDByte _send_irq_cb2_handler, $3020
        ; StoreDByte _send_irq_cb1_handler, $3040
        StoreDByte _send_irq_timer_handler, $3060
    pla
    Reverse A
    pha
        CalculateOddParity
        ror     ; Parity -> C
        lda #$ff
        ror     ; Parity -> bit 7, rest = 1
        sta ps2kb::send_last_bits  ; loaded into SR by irq handler
    pla
    sta ps2kb::VIA + IO::SR
    IO_EnableIRQ ps2kb::VIA, IO::IRQ::SR
    _EnableClock    
    rts
.endproc

; .proc _send_irq_shift_reg_handler
;     lda ps2kb::send_last_bits
;     sta ps2kb::VIA + IO::SR

;     IO_DisableIRQ ps2kb::VIA, IO::IRQ::SR
;     IO_EnableIRQ ps2kb::VIA, IO::IRQ::T2
;     ; start timer, low order count already in latch after init
;     lda #>ps2kb::TIMER_SEND
;     sta ps2kb::VIA + IO::T2CH
;     rts
; .endproc

.proc _send_irq_timer_handler
    lda ps2kb::VIA + IO::T2CL  ; clear interrupt flag
    IO_DisableIRQ ps2kb::VIA, IO::IRQ::T2

    ; disable shift register
    lda ps2kb::VIA + IO::ACR
    and #<~IO::ACR_MASK::SR
    sta ps2kb::VIA + IO::ACR
    bra _send_done

    ; lda ps2kb::VIA + IO::IFR
    ; jsr str::uint8_to_hex_str
    ; jsr lcd::print_char
    ; txa 
    ; jsr lcd::print_char
    rts
.endproc

; @details
;  Set the SEND_CMD_WAIT status bit the first time
;  and jump to _send_done the second time it is called
; .proc _send_irq_cb1_handler
;     ; clear the flag and disable interrupts
;     ; DEBUG_LED_ON 1
;     lda #'i'
;     jsr lcd::print_char
;     stp

;     lda #IO::IRQ::CB1
;     sta ps2kb::VIA + IO::IFR
;     sta ps2kb::VIA + IO::IER
;     ; DEBUG_LED_OFF 1
;     bra _check_done
; .endproc
; .proc _send_irq_cb2_handler
;     ; DEBUG_LED_ON 0
;     ; lda #'I'
;     ; jsr lcd::print_char

;     lda #IO::IRQ::CB2
;     sta ps2kb::VIA + IO::IFR
;     sta ps2kb::VIA + IO::IER
;     ; DEBUG_LED_OFF 0
;     bra _send_done
;     bra _check_done
; .endproc

; .proc _check_done
;     ; check if done, by checking if SEND_CMD_WAIT bit is set
;     lda #ps2kb::STATUS::SEND_CMD_WAIT
;     tsb ps2kb::status
;     bne _send_done     ; SEND_CMD_WAIT was already set
;     rts
; .endproc

.proc _send_done
    _DisableClock           ; disable keyboard while setting up receive
    lda #'D'
    jsr lcd::print_char
    ; Sleep 1
    lda ps2kb::status
    and #ps2kb::STATUS::SEND_CMD
    beq @status_send_data   ; data byte already sent
@status_send_cmd:
    lda #ps2kb::STATUS::SEND_DATA
    lda ps2kb::status
    ; check if a data byte needs to be sent
    lda ps2kb::send_data
    beq @send_data          ; if 0 
    cmp #ps2kb::NO_DATA
    beq @receive_answer     ; if not NO_DATA
@send_data:
    jmp _send_byte          ; send the data
@status_send_data:
@receive_answer:
    _DisableClock           ; disable keyboard while setting up receive
    DEBUG_LED_ON 0
    lda #ps2kb::STATUS::RECEIVE_ANSWER
    sta ps2kb::status
    jmp ps2kb::begin_receive
.endproc


.proc _process_cmd_answer 
    Strf fmt_answer, out_str, ps2kb::send_cmd, ps2kb::send_data, ps2kb::scancode
    PrintNC out_str
    DEBUG_LED_ON 1
    stz ps2kb::scancode
    lda ps2kb::prev_status
    sta ps2kb::status
    ; set pin to input
    ; lda ps2kb::VIA + ps2kb::CLK_PULL_DDR
    ; and #<~ps2kb::CLK_PULL_MASK
    ; sta ps2kb::VIA + ps2kb::CLK_PULL_DDR
    rts
.endproc


out_idx: .res 1
out_str: .res 40
char:           .res 1
keycode:        .res 1
keycode_flags:  .res 1
fmt_codechar:   .asciiz "%x %x %c "
fmt_code:       .asciiz "%x %x   "
fmt_answer:     .asciiz "%x-%x>%x"