spicode.s65

@@ -3,7 +3,7 @@
 .include "lcd.h65"
 .include "math.h65"
 .include "keypad.h65"
-.include "keyboard_handler.h65"
+.include "keyboard.h65"
 .include "chars.h65"
 .import homeloop:absolute
 .import home:absolute
@@ -25,49 +25,47 @@ CODE_START:
     DEBUG_LED_OFF 1
     DEBUG_LED_OFF 2
 
-    StoreDByte kb_irq1, ARG0
+    lda #<kb_irq1
-    StoreDByte $3000, ARG2
+    sta ARG0
-    ; lda #<kb_irq1
+    lda #>kb_irq1
-    ; sta ARG0
+    sta ARG1
-    ; lda #>kb_irq1
+    lda #<$3000
-    ; sta ARG1
+    sta ARG2
-    ; lda #<$3000
+    lda #>$3000
-    ; sta ARG2
+    sta ARG3
-    ; lda #>$3000
-    ; sta ARG3
     ldy #10
     jsr memcopy
 
-    StoreDByte kb_irq2, ARG0
+    lda #<kb_irq2
-    StoreDByte $3100, ARG2
+    sta ARG0
-    ; lda #<kb_irq2
+    lda #>kb_irq2
-    ; sta ARG0
+    sta ARG1
-    ; lda #>kb_irq2
+    lda #<$3100
-    ; sta ARG1
+    sta ARG2
-    ; lda #<$3100
+    lda #>$3100
-    ; sta ARG2
+    sta ARG3
-    ; lda #>$3100
-    ; sta ARG3
     ldy #10
     jsr memcopy
 
 
-    jsr ps2kb::init
+    ; PrintNC $3000
+
+    jsr kb::init
+
     stz kb::status
-    StoreDByte process_scancode,ps2kb::scancode_handler
-    jsr ps2kb::begin_receive
 
     lda #'%'
     jsr lcd::print_char
 
     stz kp::_DEBUG_VAL
     ldy #0
+
 @loop:
     wai
-    lda ps2kb::scancode
+    lda kb::scancode
     beq @noscancode
     jsr process_scancode
-    stz ps2kb::scancode
+    stz kb::scancode
     lda char
     beq @onlykeycode
     Strf fmt_codechar,out_str,keycode,kb::status,char
@@ -133,7 +131,7 @@ CODE_START:
     iny
     jmp @loop
 @lA:
-    lda ps2kb::VIA + IO::SR
+    lda kb::KB_IO + IO::SR
     jsr lcd::print_char
     jmp @loop
 @lB:
@@ -156,7 +154,7 @@ CODE_START:
 kb_irq1:
     ; lda #'!'
     ; jsr lcd::print_char
-    jsr ps2kb::_receive_irq_shift_reg_handler
+    jsr kb::irq_shift_reg_handler
     ; lda #':'
     ; jsr lcd::print_char
     rts
@@ -165,7 +163,7 @@ kb_irq2:
     ; lda #'?'
     ; jsr lcd::print_char
     ; jsr kb::on_timer_irq
-    jsr ps2kb::_receive_irq_timer_handler
+    jsr kb::irq_timer_handler
     ; lda #';'
     ; jsr lcd::print_char
     rts
@@ -174,7 +172,7 @@ kb_irq2:
 .proc process_scancode
     ; DEBUG_LED_OFF 1
     ; check how this scancode needs to be interpreted
-    ldx ps2kb::scancode
+    ldx kb::scancode
     bit kb::status
     jmi release_key   ; bit 7 set
     bvs @twobytecode  ; bit 6 set

system/io_W65C22.h65

@@ -109,24 +109,5 @@ INCLUDE_IOW65C22 = 1
     IRQ  = %10000000
 .endenum
 
-;;********************************************************************************
-;; @macro Enable an interrupt source
-;; @modifies: A
-;; @param flag: A flag of the interrupt flag register (IO:IRQ)
-;;********************************************************************************
-.macro IO_EnableIRQ ioaddr, flag
-    lda #(IO::IRQ::IRQ | flag)
-    sta ioaddr + IO::IER
-.endmacro
-;;********************************************************************************
-;; @macro Disable an interrupt source
-;; @modifies: A
-;; @param flag: A flag of the interrupt flag register (IO:IRQ)
-;;********************************************************************************
-.macro IO_DisableIRQ ioaddr, flag
-    lda #flag
-    sta ioaddr + IO::IER
-.endmacro
-
 .endscope ; IO
 .endif  ; guard

system/keyboard.h65

@@ -1,17 +1,25 @@
 ;;********************************************************************************
-;; @module keyboard_handler 
+;; @module keyboard 
-;; @type system
+;; @type drive
 ;; @details:
-;;	This module processes keyboard scancodes from the ps2_keyboard module.
+;;  Support for a PS2 Keyboard using the shift register of a 6522 VIA
+;;  Pressing a key causes 11 bits to be sent: 1 start - 8 scancode - 1 parity - 1 stop 
+;;  The VIA is set up to interrupt after 8 bits have been shifted into the shift register
+;;  from the external clock pulses of the keyboard (additional hardware required to 
+;;  address the hardware bug of the VIA, where bit get lost when the external clock 
+;;  transition happens during falling edge of PHI2). After reading the shift register,
+;;  the VIAs T2 timer is set to interrupt after the last 3 bits have been shifted in,
+;;  which takes about ~230ms.
 ;;********************************************************************************
 .ifndef INCLUDE_KEYBOARD
 INCLUDE_KEYBOARD = 1
-
+.include "system.h65"
-.include "ps2_keyboard.h65"
 
 .scope kb
+Import kb,init,irq_shift_reg_handler,irq_timer_handler,scancode,key_read
 Import kb, CHARS_NOMOD, CHARS_MODSHIFT
 ImportZp kb,status
+KB_IO = IO1
 
 .enum STATUS
     RELEASE			= %10000000
@@ -137,5 +145,7 @@ K_RELEASE			= $F0
 	PAGEUP          = $7D
 .endenum
 
+
 .endscope
+
 .endif  ; guard

system/keyboard.s65

@@ -0,0 +1,138 @@
+.include "keyboard.h65"
+.include "string.h65"
+.include "lcd.h65"
+Export kb,init,irq_shift_reg_handler,irq_timer_handler,scancode,key_read
+Export kb, CHARS_NOMOD, CHARS_MODSHIFT
+ExportZp kb,status
+
+.zeropage
+status: 
+.bss
+key_read: .res 2
+scancode:  .res 1
+
+.code
+;;********************************************************************************
+;; @function Initialize the PS2 keyboard
+;; @modifies: A
+;;********************************************************************************
+.proc init
+    ; - use the shift register interrupts to read the first 8 bits
+    ;   set shift register to shift in under external clock on CB1
+    ; - configure timer for timing the read of the last 3 bits
+    ;   timer 2 one shot mode is sufficient, leaves T1 available
+    lda #(IO::ACR::SR_SIN_PHIE | IO::ACR::T2_IRQ_LOAD)
+    tsb kb::KB_IO + IO::ACR
+    ; the 3 last bits take about 230us, at @1MHz => wait 230 cycles and then the shift register
+    ; (this could be shorter since the it takes a few cycles after the interrupt)
+    lda #230
+    sta kb::KB_IO + IO::T2CL
+    stz key_read
+    stz key_read+1
+    stz scancode
+    stz status
+
+    ; enable SR interrupts
+    lda #(IO::IRQ::IRQ | IO::IRQ::SR)
+    sta kb::KB_IO + IO::IER
+    ; load SR to reset
+    lda kb::KB_IO + IO::SR
+    rts
+.endproc
+
+
+;;********************************************************************************
+;; @function Read the first 8 bits an
+;; @modifies: A
+;; @details
+;;  - read shift register
+;;  - disable shift register interrupts
+;;  - reset shift register
+;;  - enable timer 2 interrupts
+;;  - start timer 2
+;;  IO::SR has to be read before the next bit is shifted in, which happens ~75us after the irq
+;;  at 1MHz, handling this interrupt takes about 50us (without any additional debug code),
+;;  so it should work
+;;********************************************************************************
+.proc irq_shift_reg_handler
+    lda kb::KB_IO + IO::SR
+    sta key_read
+    stz kb::KB_IO + IO::SR
+
+    ; disable SR interrupts
+    lda #IO::IRQ::SR
+    sta kb::KB_IO + IO::IER
+    ; enable timer interrupts
+    lda #(IO::IRQ::IRQ | IO::IRQ::T2)
+    sta kb::KB_IO + IO::IER
+    ; start timer, low order count already in latch after init
+    lda #0
+    sta kb::KB_IO + IO::T2CH
+    rts
+.endproc
+
+
+;;********************************************************************************
+;; @function Read the last 3 bits after after timer 2 is up
+;; @modifies: A
+;; @details
+;;  - read shift register
+;;  - disable timer 2 interrupts
+;;  - enable shift register interrupts
+;;  - reset shift register
+;;********************************************************************************
+.proc irq_timer_handler
+    lda kb::KB_IO + IO::SR
+    sta key_read + 1
+
+    lda kb::KB_IO + IO::T2CL  ; clear interrupt flag
+
+    ; disable timer interrupts
+    lda #(IO::IRQ::T2)
+    sta kb::KB_IO + IO::IER
+
+    ; reset SR
+    ; disabling shifting in acr seems necessary to reset - otherwise
+    ; it continues counting and interrupts after the first 5 bits of the next keypress
+    lda #(IO::ACR::SR_SIN_PHIE | IO::ACR::T2_IRQ_LOAD)
+    trb kb::KB_IO + IO::ACR
+    tsb kb::KB_IO + IO::ACR
+    stz kb::KB_IO + IO::SR
+    ; enable shift register interrupts
+    lda #(IO::IRQ::IRQ | IO::IRQ::SR)
+    sta kb::KB_IO + IO::IER
+
+    lda key_read+1
+    ror
+    ror
+    ror
+    lda key_read  ; not affecting carry
+    rol           ; rotate carry into byte, rotate startbit into carry
+    Reverse A
+    sta scancode
+
+    rts
+.endproc
+
+.rodata
+.align 256
+CHARS_NOMOD:
+        .byte "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00^\x00"
+        .byte "\x00\x00\x00\x00\x00q1\x00\x00\x00ysaw2\x00"
+        .byte "\x00cxde43\x00\x00 vftr5\x00"
+        .byte "\x00nbhgz6\x00\x00\x00mju78\x00"
+        .byte "\x00,kio09\x00\x00.-l\xEFp\xE2\x00"
+        .byte "\x00\x00\xE1\x00\xF5`\x00\x00\x00\x00\x00\x00\x00#\x00\x00"
+        .byte "\x00<\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+        .byte "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+
+.align 256
+CHARS_MODSHIFT:
+        .byte "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xDF\x00"
+        .byte "\x00\x00\x00\x00\x00Q!\x00\x00\x00YSAW\"\x00"
+        .byte "\x00CXDE$\xED\x00\x00 VFTR%\x00"
+        .byte "\x00NBHGZ&\x00\x00\x00MJU/(\x00"
+        .byte "\x00;KIO=)\x00\x00:_L\xEFP\xE2\x00"
+        .byte "\x00\x00\xE1\x00\xF5`\x00\x00\x00\x00\x00\x00\x00'\x00\x00"
+        .byte "\x00>\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+        .byte "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"

system/keyboard_handler.s65

@@ -1,28 +0,0 @@
-.include "keyboard_handler.h65"
-Export kb, CHARS_NOMOD, CHARS_MODSHIFT
-ExportZp kb,status
-.zeropage
-status:         .res 1
-
-.rodata
-.align 256
-CHARS_NOMOD:
-        .byte "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00^\x00"
-        .byte "\x00\x00\x00\x00\x00q1\x00\x00\x00ysaw2\x00"
-        .byte "\x00cxde43\x00\x00 vftr5\x00"
-        .byte "\x00nbhgz6\x00\x00\x00mju78\x00"
-        .byte "\x00,kio09\x00\x00.-l\xEFp\xE2\x00"
-        .byte "\x00\x00\xE1\x00\xF5`\x00\x00\x00\x00\x00\x00\x00#\x00\x00"
-        .byte "\x00<\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
-        .byte "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
-
-.align 256
-CHARS_MODSHIFT:
-        .byte "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xDF\x00"
-        .byte "\x00\x00\x00\x00\x00Q!\x00\x00\x00YSAW\"\x00"
-        .byte "\x00CXDE$\xED\x00\x00 VFTR%\x00"
-        .byte "\x00NBHGZ&\x00\x00\x00MJU/(\x00"
-        .byte "\x00;KIO=)\x00\x00:_L\xEFP\xE2\x00"
-        .byte "\x00\x00\xE1\x00\xF5`\x00\x00\x00\x00\x00\x00\x00'\x00\x00"
-        .byte "\x00>\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
-        .byte "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"

system/ps2_keyboard.h65

@@ -1,51 +0,0 @@
-;;********************************************************************************
-;; @module ps2_keyboard 
-;; @type driver
-;; @details:
-;;  Support for a PS2 Keyboard using the shift register of a 6522 VIA
-;;  @section Reading a scancode/command answer
-;;   Pressing a key causes 11 bits to be sent: 1 start - 8 scancode - 1 parity - 1 stop 
-;;   The VIA is set up to interrupt after 8 bits have been shifted into the shift register
-;;   from the external clock pulses of the keyboard (additional hardware required to 
-;;   address the hardware bug of the VIA, where bit get lost when the external clock 
-;;   transition happens during falling edge of PHI2). After reading the shift register,
-;;   the VIAs T2 timer is set to interrupt after the last 3 bits have been shifted in,
-;;   which takes about ~230ms.
-;;	 T2 is used because it leaves to more versatile T1 available for something else
-
-;;  @section Processing a scancode
-;;	 The scancode may be processed by storing the address of a handler subroutine in
-;;	 ps2kb::scancode_handler. This handler can load the scancode byte from ps2kb::scancode.
-;;
-;;  
-;;  To use a different layout, change the enum K and the CHARS_NOMOD and CHARS_MODSHIFT
-;; @warning
-;;  The value with which the timer is loaded must depends on the clock frequency
-;;	of the keyboard and the computer
-;;  
-;;********************************************************************************
-.ifndef INCLUDE_PS2_KEYBOARD
-INCLUDE_PS2_KEYBOARD = 1
-.include "system.h65"
-
-.scope ps2kb
-Import ps2kb,init,begin_receive,send_command,scancode,status,scancode_handler
-Import ps2kb, _receive_irq_shift_reg_handler, _receive_irq_timer_handler
-
-VIA = IO1
-TIMER = 230  ; 230 ms (@1MHz)
-; use RA4 to pull the clock low
-CLK_PULL_MASK= %00001000
-CLK_PULL_R	 = IO::RANH
-CLK_PULL_DDR = IO::DDRA
-
-
-.enum STATUS
-    RECEIVE_KEYS	= %10000000
-    RECEIVE_ANSWER	= %01000000
-    SEND_CMD   		= %00100000
-    NONE			= %00000000
-.endenum
-.endscope
-
-.endif  ; guard

system/ps2_keyboard.s65

@@ -1,313 +0,0 @@
-.include "ps2_keyboard.h65"
-.include "string.h65"
-.include "lcd.h65"
-.include "parity.h65"
-Export ps2kb,init,begin_receive,send_command,scancode,status,scancode_handler
-Export ps2kb, _receive_irq_shift_reg_handler, _receive_irq_timer_handler
-
-.bss
-status:                 .res 1
-send_last_bits:         .res 1
-send_data:              .res 1
-send_cmd:               .res 1
-key_read:               .res 2
-scancode:               .res 1
-scancode_handler:       .res 2
-
-.code
-
-;;********************************************************************************
-;; @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::CLK_PULL_DDR
-    and #<~ps2kb::CLK_PULL_MASK
-    sta ps2kb::VIA + ps2kb::CLK_PULL_DDR
-.endmacro
-
-.macro _DisableTimerIRQ
-    ; set pin to input
-    lda ps2kb::VIA + ps2kb::CLK_PULL_DDR
-    and #<~ps2kb::CLK_PULL_MASK
-    sta ps2kb::VIA + ps2kb::CLK_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::CLK_PULL_DDR
-    ora #ps2kb::CLK_PULL_MASK
-    sta ps2kb::VIA + ps2kb::CLK_PULL_DDR
-    ; set pin low
-    lda ps2kb::VIA + ps2kb::CLK_PULL_R
-    and #<~ps2kb::CLK_PULL_MASK
-    sta ps2kb::VIA + ps2kb::CLK_PULL_R
-.endmacro
-
-
-.proc init
-    stz key_read 
-    stz key_read+1
-    stz scancode
-    stz status
-    ; T2 oneshot mode, clear shift reg
-    lda ps2kb::VIA + IO::ACR
-    and #<~IO::ACR_MASK::SR
-    ora #IO::ACR::T2_IRQ_LOAD
-    sta ps2kb::VIA + IO::ACR
-    ; the 3 last bits take about 230us, at @1MHz => wait 230 cycles and then the shift register
-    ; (this could be shorter since the it takes a few cycles after the interrupt)
-    lda #<ps2kb::TIMER
-    sta ps2kb::VIA + IO::T2CL
-    ; load this rts as scancode_handler
-    StoreDByte @rts, scancode_handler
-@rts:
-    rts
-.endproc
-
-
-;;********************************************************************************
-;; @function Start receiving data from the keyboard
-;; @details
-;;  - use the shift register interrupts to read the first 8 bits
-;;  - configure timer for timing the read of the last 3 bits
-;; @modifies: A
-;;********************************************************************************
-.proc begin_receive
-    ; disable timer interrupts (this might be called while waiting on the last 3 bits)
-    IO_DisableIRQ ps2kb::VIA, IO::IRQ::T2
-    ; set shift register to shift in under external clock on CB1
-    lda ps2kb::VIA + IO::ACR
-    and #<~IO::ACR_MASK::SR
-    ora #IO::ACR::SR_SIN_PHIE
-    sta ps2kb::VIA + IO::ACR
-    stz key_read
-    stz key_read+1
-    stz scancode
-    bit status
-    ; set to RECEIVE_KEYS only if RECEIVE_ANSWER is not set
-    bvs @receive_answer
-    lda #ps2kb::STATUS::RECEIVE_KEYS
-    sta status
-@receive_answer:
-
-    _EnableClock
-
-    ; todo setup irq handlers
-
-    IO_EnableIRQ ps2kb::VIA, IO::IRQ::SR
-    ; reset and start SR
-    stz ps2kb::VIA + IO::SR
-    rts
-.endproc
-
-
-;;********************************************************************************
-;; @function Read the first 8 bits an
-;; @modifies: A
-;; @details
-;;  - read shift register
-;;  - disable shift register interrupts
-;;  - reset shift register
-;;  - enable timer 2 interrupts
-;;  - start timer 2
-;;  IO::SR has to be read before the next bit is shifted in, which happens ~75us after the irq
-;;  at 1MHz, handling this interrupt takes about 50us (without any additional debug code),
-;;  so it should work
-;;********************************************************************************
-.proc _receive_irq_shift_reg_handler
-    lda ps2kb::VIA + IO::SR
-    sta key_read
-    stz 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
-    sta ps2kb::VIA + IO::T2CH
-    rts
-.endproc
-
-
-;;********************************************************************************
-;; @function Read the last 3 bits after after timer 2 is up
-;; @modifies: A
-;; @details
-;;  - read shift register
-;;  - disable timer 2 interrupts
-;;  - enable shift register interrupts
-;;  - reset shift register
-;;  - jump to the subroutine pointed to by scancode_handler
-;;********************************************************************************
-.proc _receive_irq_timer_handler
-    lda ps2kb::VIA + IO::SR
-    sta key_read + 1
-
-    lda ps2kb::VIA + IO::T2CL  ; clear interrupt flag
-
-    IO_DisableIRQ ps2kb::VIA, IO::IRQ::T2
-    ; reset SR
-    ; disabling shifting in acr seems necessary to reset - otherwise
-    ; it continues counting and interrupts after the first 5 bits of the next keypress
-    lda #(IO::ACR::SR_SIN_PHIE | IO::ACR::T2_IRQ_LOAD)
-    trb ps2kb::VIA + IO::ACR
-    tsb ps2kb::VIA + IO::ACR
-    stz ps2kb::VIA + IO::SR
-    IO_EnableIRQ ps2kb::VIA, IO::IRQ::SR
-
-    lda key_read+1
-    ror             ; stop bit -> C
-    sta key_read+1  ; parity in bit 0, D7 in bit 1
-    ror             ; parity -> C
-    ror             ; D7 -> C
-    lda key_read  ; not affecting carry
-    rol             ; C  -> bit 0, startbit -> C
-    Reverse A
-    sta scancode
-    CalculateOddParity
-    eor key_read+1  ; if bit 0 is 1 - parity error
-    and #1          ; bit 1 is still D7
-    bne @parity_error
-    ; check what to do with the scancode
-    bit status
-    bcc @status_not_receive_keys
-    jmp (scancode_handler)
-@status_not_receive_keys:
-    bvc @status_ignore
-    jmp _process_cmd_answer 
-@status_ignore:
-    rts
-@parity_error:  ; TODO handle somehow
-    lda #$ff
-    sta scancode
-    DEBUG_LED_ON 2
-    rts
-.endproc
-
-
-;;********************************************************************************
-;; @function Send a command to the keyboard
-;; @modifies: A,X,Y
-;; @param A: The command byte
-;; @param X: The data byte or 0 if only the command byte should be sent
-;;********************************************************************************
-.proc send_command
-    sta send_cmd        ; store if it needs to be resent
-    cpx #0
-    beq @jmp_send_byte
-@store_data:
-    stx send_data
-@jmp_send_byte:
-    jmp _send_byte
-.endproc
-
-
-;;********************************************************************************
-;; @function Send a byte to the keyboard
-;; @modifies: A,X,Y
-;; @param A: The byte to send
-;; @details
-;;  - pull clock low to stop keyboard transmissions
-;;  - setup shift register to shift out
-;;  - put startbit + D0-6 in shift register
-;;  - store D7 + parity + stopbit in memory
-;;  - TODO setup SR and T2 interrupt handlers
-;;********************************************************************************
-.proc _send_byte
-    pha
-        IO_DisableIRQ ps2kb::VIA, IO::IRQ::T2
-        _DisableClock
-        ; (re)set shift register to shift out under external clock on CB1
-        lda ps2kb::VIA + IO::ACR
-        and #<~IO::ACR_MASK::SR
-        ora #IO::ACR::SR_SOUT_PHIE
-        sta ps2kb::VIA + IO::ACR
-        IO_EnableIRQ ps2kb::VIA, IO::IRQ::SR
-    pla
-    pha
-        ; split into the 11 bits
-        CalculateOddParity
-        tax
-    pla
-    clc     ; C = 0 (startbi)
-    rol     ; C -> bit 0, D7 -> C
-    sta ps2kb::VIA + IO::SR
-    txa
-    ror     ; C -> bit 0 (D7)
-    ora #%00000100  ; set stopbit
-    ; A = 000001P7  where 7 = D7, P = Parity
-    sta send_last_bits  ; loaded into SR by irq handler
-    ; stop pulling clk low, which causes the startbit to be shifted out 
-    _EnableClock    
-    rts
-.endproc
-
-
-;;********************************************************************************
-;; @function Send the lasts 3 bits 
-;; @modifies: A
-;; @details
-;;  - load the remaining 3 bits of the transmission into the shift register
-;;  - disable shift register interrupts
-;;  - enable timer 2 interrupts
-;;  - start timer 2
-;;********************************************************************************
-.proc _send_irq_shift_reg_handler
-    lda send_last_bits
-    sta ps2kb::VIA + IO::SR
-
-    ; disable SR interrupts
-    lda #IO::IRQ::SR
-    sta ps2kb::VIA + IO::IER
-    ; enable timer interrupts
-    lda #(IO::IRQ::IRQ | IO::IRQ::T2)
-    sta ps2kb::VIA + IO::IER
-    ; start timer, low order count already in latch after init
-    lda #>ps2kb::TIMER
-    sta ps2kb::VIA + IO::T2CH
-    rts
-.endproc
-
-
-;;********************************************************************************
-;; @function Send databyte or reveice the keyboards answer
-;; @modifies: A, X, Y
-;; @details
-;;  - disable timer 2 interrupts
-;;  - if send_data is zero:
-;;      - begin_receive
-;;      - set status RECEIVE_ANSWER
-;;  - else
-;;      - send_byte send_data
-;;      - set send_data = 0
-;;********************************************************************************
-.proc _send_irq_timer_handler
-    lda ps2kb::VIA + IO::T2CL  ; clear interrupt flag
-    IO_DisableIRQ ps2kb::VIA, IO::IRQ::T2
-    ; no SR reset necessary, will be done in begin_receive or send_byte
-
-    lda send_data
-    beq @receive
-    stz send_data
-    jmp _send_byte
-    rts
-@receive:
-    lda #ps2kb::STATUS::RECEIVE_ANSWER
-    sta status
-    jmp begin_receive
-.endproc
-
-
-.proc _process_cmd_answer
-@success:
-    rts
-.endproc

util/parity.h65

@@ -1,35 +0,0 @@
-.ifndef INCLUDE_PARITY
-INCLUDE_PARITY = 1
-
-.import count_set_bits
-
-;;********************************************************************************
-;; @macro Calculate even parity
-;; @modifies: A, X, Y
-;; @returns A: 0 - even number of set bits, 1 - uneven number of set bits
-;; @returns Y: The number of set bits in the byte
-;;********************************************************************************
-.macro CalculateEvenParity
-    jsr count_set_bits
-    tya
-    and #1
-.endmacro
-
-
-;;********************************************************************************
-;; @macro Calculate odd parity
-;; @details
-;;  Count the number of set bits in Y.
-;;  
-;; @modifies: A, X, Y
-;; @returns A: 1 - even number of set bits, 0 - uneven number of set bits
-;; @returns Y: The number of set bits in the byte
-;;********************************************************************************
-.macro CalculateOddParity
-    jsr count_set_bits
-    tya
-    and #1
-    eor #1
-.endmacro
-
-.endif  ; guard

util/parity.s65

@@ -1,23 +0,0 @@
-.export count_set_bits
-;;********************************************************************************
-;; @function Initialize the PS2 keyboard
-;; @details
-;;  Count the number of set bits in Y.
-;;  
-;; @modifies: A, X, Y
-;; @returns Y: The number of set bits in the byte
-;;********************************************************************************
-.proc count_set_bits
-    ldx #8
-    ldy #0  ; number of set bits
-@loop:
-    dex 
-    beq @done
-    ror
-    bcc @loop
-@set:
-    iny
-    bra @loop
-@done:
-    rts
-.endproc

utility.h65

@@ -36,35 +36,6 @@ INCLUDE_UTILITY = 1
 .endmacro
 
 
-;;********************************************************************************
-;; @macro Store a double byte (immediate) at an address
-;; @param addr      Address, double byte will be loaded in LE to addr, addr+1 
-;; @param dbyte     Location or value
-;; @param reg       Register, defaults to A
-;; @modifies        
-;;********************************************************************************
-.macro StoreDByte dbyte,addr,reg
-    ; .out .sprintf("%x, %x", dbyte, addr)
-.if .blank(reg) .or .match(reg, A)
-    lda #<dbyte
-    sta addr
-    lda #>dbyte
-    sta addr+1
-.elseif .match(reg, X)
-    ldx #<dbyte
-    stx addr
-    ldx #>dbyte
-    stx addr+1
-.elseif .match(reg, Y)
-    ldy #<dbyte
-    sty addr
-    ldy #>dbyte
-    sty addr+1
-.else
-    .fatal "Invalid reg given to StoreDByte"
-.endif
-.endmacro
-
 ;;********************************************************************************
 ;; @macro Update a byte in memory using a mask
 ;; @param addr       Address of the byte to update
@@ -85,7 +56,6 @@ INCLUDE_UTILITY = 1
 .endmacro
 
 
-
 ;;********************************************************************************
 ;; @macro Jump to the subroutine and let the routine return at another location
 ;; @details