mouse.asm

一款支持 ｐｓ２ 的鼠标程序。经过验证

	movwf TEMP1
	PacketOutLoop movf INDF, w ;Get data byte
	call ByteOut ; Output that byte
	xorlw0xFF ;Test for RTS error
	bz PacketIn
	xorlw0xFE ^ 0xFF ;Test for inhibit error
	bz PacketOut
	incf FSR, f ;Point to next byte
	decfsz TEMP1, f
	goto PacketOutLoop
	goto MainLoop
	;---------------------------------------------------------------------------------------------
	; READ PACKET
	;---------------------------------------------------------------------------------------------
	PacketIn call ByteIn
	xorlw0xFF ;Test for parity/framing error
	bz Mouse_ERR
	xorlw0xFE ^ 0xFF ;Test for inhibit error
	bz MainLoop1
	movlw 0xFE ;Test for "Resend" command
	xorwf RECEIVE, w
	bz PacketOut
	Acknowledge movlw 0xFA ;Acknowledge
	call ByteOut
	goto Command
	;---------------------------------------------------------------------------------------------
	; READ INPUTS:
	;---------------------------------------------------------------------------------------------
	ReadInputs movlw DISTANCE
	btfss PS2_Xp ;Read inputs
	addwf X_COUNTER, f
	btfss PS2_Yp
	addwf Y_COUNTER, f
	btfss PS2_Xn
	subwf X_COUNTER, f
	btfss PS2_Yn
	
	
		subwf Y_COUNTER, f
	bcf XY_FLAGS, xSIGN
	btfsc X_COUNTER, 7
	bsf XY_FLAGS, xSIGN
	bcf XY_FLAGS, ySIGN
	btfsc Y_COUNTER, 7
	bsf XY_FLAGS, ySIGN
	movf XY_FLAGS, w ;Get previous button states
	andlw b'00000111'
	btfss PS2_Bl ;Find changes in button states
	xorlwb'00000001'
	btfss PS2_Br
	xorlwb'00000010'
	movwf dBUTTONS ;Save *change* in button state
	retlw 0x00
	;---------------------------------------------------------------------------------------------
	; WRAP MODE:
	;---------------------------------------------------------------------------------------------
	WrapMode btfsc DATA ;Wait for RTS
	goto WrapMode
	call ByteIn ;Read one byte from host
	xorlw0xFE ;Test for aborted transmission
	bz WrapMode
	movf RECEIVE, w
	xorlw0xFF ;Test for "Reset" command
	bz Acknowledge
	xorlw0xFF^0xEC ;Test for "Reset Wrap Mode" command
	bz Acknowledge
	xorlw0xEC
	call ByteOut ;Else, echo
	goto WrapMode
	;---------------------------------------------------------------------------------------------
	; LOAD DEFAULT VALUES:
	;---------------------------------------------------------------------------------------------
	LoadDefaults movlw 100 ;Default report rate
	movwf REPORT_RATE
	movlw 0x02 ;Default resolution
	movwf RESOLUTION
	clrf FLAGS ;Stream mode, 1:1 scaling, disabled
	retlw 0x00
	
	
		;---------------------------------------------------------------------------------------------
	; EMULATE BAT:
	;---------------------------------------------------------------------------------------------
	BATdelay clrf TEMP0 ;Used for a 400 ms delay at power-on
	clrf TEMP1
	DelayLoop Delay 6
	decfsz TEMP0, f
	goto DelayLoop
	decfsz TEMP1, f
	goto DelayLoop
	retlw 0x00
	;---------------------------------------------------------------------------------------------
	; HANDLE COMMANDS:
	;---------------------------------------------------------------------------------------------
	SetResolution movf RECEIVE, w
	movwf RESOLUTION
	goto MainLoop
	SetReportRate movf RECEIVE, w
	movwf REPORT_RATE
	goto MainLoop
	;0xE6 - Set Scaling 1:1
	Mouse_E6 bcf FLAGS, SCALE
	goto MainLoop
	;0xE7 - Set Scaling 2:1
	Mouse_E7 bsf FLAGS, SCALE
	goto MainLoop
	;0xE9 - Status Request
	Mouse_E9 movf FLAGS, w
	btfss PS2_Bl
	iorlw 0x04
	btfss PS2_Br
	iorlw 0x01
	movwf SEND1
	movf RESOLUTION, w
	movwf SEND2
	movf REPORT_RATE, w
	movwf SEND3
	movlw 0x03
	movwf LENGTH
	
	
	goto PacketOut
	;0xEA - Set Stream Mode
	Mouse_EA bcf FLAGS, MODE
	goto MainLoop
	;0xF0 - Set Remote Mode
	Mouse_F0 bsf FLAGS, MODE
	goto MainLoop
	;0xF2 - Get Device ID
	Mouse_F2 clrf SEND1
	movlw 0x01
	movwf LENGTH
	goto PacketOut
	;0xF4 - Enable Reporting
	Mouse_F4 bsf FLAGS, ENABLE
	goto MainLoop
	;0xF5 - Disable Reporting
	Mouse_F5 bcf FLAGS, ENABLE
	goto MainLoop
	;0xF6 - Set Default
	Mouse_F6 call LoadDefaults
	goto MainLoop
	;Invalid command
	Mouse_ERR movlw 0xFE
	call ByteOut
	goto MainLoop
	;---------------------------------------------------------------------------------------------
	; OUTPUT ONE BYTE: - TIMING IS CRITICAL!!!
	;---------------------------------------------------------------------------------------------
	ByteOut movwf TEMP0
	InhibitLoop btfss CLOCK ;Test for inhibit
	goto InhibitLoop
	Delay 100 ;(50 microsec = 58 clock cycles, min)
	btfss CLOCK
	goto InhibitLoop
	btfss DATA ;Check for request-to-send
	retlw 0xFF
	clrf PARITY
	
	movlw 0x08
	movwf COUNTER
	movlw 0x00
	call BitOut ;Start bit (0)
	btfss CLOCK ;Test for inhibit
	goto ByteOutEnd
	Delay 4
	ByteOutLoop movf TEMP0, w
	xorwf PARITY, f
	call BitOut ;Data bits
	btfss CLOCK ;Test for inhibit
	goto ByteOutEnd
	rrf TEMP0, f
	decfsz COUNTER, f
	goto ByteOutLoop
	Delay 2
	comf PARITY, w
	call BitOut ;Parity bit
	btfss CLOCK ;Test for inhibit
	goto ByteOutEnd
	Delay 5
	movlw 0xFF
	call BitOut ;Stop bit (1)
	Delay 48
	retlw 0x00
	ByteOutEnd bsf STATUS, RP0
	bsf DATA
	bsf CLOCK
	bcf STATUS, RP0
	retlw 0xFE
	BitOut bsf STATUS, RP0
	andlw 0x01
	btfss STATUS, Z
	bsf DATA
	btfsc STATUS, Z
	bcf DATA
	Delay 21
	bcf CLOCK
	Delay 45
	bsf CLOCK
	bcf STATUS, RP0
	Delay 5
	return
	;---------------------------------------------------------------------------------------------
	
	; READ ONE BYTE: (Takes about 1ms) - TIMING IS CRITICAL!!!
	;---------------------------------------------------------------------------------------------
	ByteIn btfss CLOCK ;Test for Request-to-send
	retlw 0xFE
	btfsc DATA
	retlw 0xFE
	movlw 0x08
	movwf COUNTER
	clrf PARITY
	Delay 28
	ByteInLoop call BitIn ;Data bits
	btfss CLOCK ;Test for inhibit
	retlw 0xFE
	bcf STATUS, C
	rrf RECEIVE, f
	iorwf RECEIVE, f
	xorwf PARITY,f
	decfsz COUNTER, f
	goto ByteInLoop
	Delay 1
	call BitIn ;Parity bit
	btfss CLOCK ;Test for inhibit
	retlw 0xFE
	xorwf PARITY, f
	Delay 5
	ByteInLoop1 Delay 1
	call BitIn ;Stop bit
	btfss CLOCK ;Test for inhibit
	retlw 0xFE
	xorlw0x00
	btfsc STATUS, Z
	clrf PARITY
	btfsc STATUS, Z ;Stop bit = 1?
	goto ByteInLoop1 ; No--keep clocking.
	bsf STATUS, RP0 ;Acknowledge
	bcf DATA
	Delay 11
	bcf CLOCK
	Delay 45
	bsf CLOCK
	Delay 7
	bsf DATA
	bcf STATUS, RP0
	
	btfss PARITY, 7 ;Parity correct? 
	retlw 0xFF ; No--return error 
	Delay 45 
	retlw  0x00   
	BitIn Delay    8 
	bsf STATUS, RP0 
	bcf CLOCK 
	Delay 45 
	bsf CLOCK 
	bcf STATUS, RP0 
	Delay 21 
	btfsc DATA 
	retlw 0x80 
	retlw 0x00 ;-------------------------------------
	
	
	--------------------------- ; DELAY: ;-------------
	--------------------------------------------------------------------------------
	;Delays 4w+4 cycles (including call,return, and movlw) (0=256) 
	Delay_us addlw -1 ;Precise delays used in I/O 
	btfss STATUS, Z 
	goto Delay_us 
	return
	 end