SetPorts bsf STATUS, RP0 ;select bank 1
movlw 0x00 ;make all LED pins outputs
movwf LED_TRIS
movlw b'11111111' ;make all IR port pins inputs
movwf IR_TRIS
bcf STATUS, RP0 ;select bank 0
Main
call ReadIR ;read IR signal
call ProcKeys ;do something with commands received
goto Main ;loop for ever
ProcKeys
btfss Flags2, New
retlw 0x00 ;return if not new keypress
movlw TV_ID ;check for TV ID code
subwf Dev_Byte,w
btfss STATUS, Z
retlw 0x00 ;return if not correct code
movlw But1 ;test for button 1
subwf Cmd_Byte, w ;moves code into w and sub’s versus
btfss STATUS, Z ;cmd_byte, if zero, test which key.
goto Key1 ;try next key if not correct code
bsf LED_PORT,LED0 ;turn on LED
call LED_5sec ;Routine, led on for 5 seconds
bcf LED_PORT,LED0 ;turn off LED
bcf Flags2, New ;and cancel new flag
retlw 0x00
Key1 movlw But2 ;test for button 1
subwf Cmd_Byte, w
btfss STATUS, Z
goto Key2 ;try next key if not correct code
bsf LED_PORT, LED1 ;turn on LED
call LED_5sec ;5 seconds logic 1
bcf LED_PORT, LED1 ;turn off LED
bcf Flags2, New ;and cancel new flag
retlw 0x00
Key2 movlw But3 ;test for button 1
subwf Cmd_Byte, w
btfss STATUS, Z
goto Key3 ;try next key if not correct code
bsf LED_PORT, LED2 ;turn on LED
call LED_5sec ;5 seconds logic 1
bcf LED_PORT, LED2 ;turn off LED
bcf Flags2, New ;and cancel new flag
retlw 0x00
Key3 movlw But4 ;test for button 1
subwf Cmd_Byte, w
btfss STATUS, Z
goto Key4 ;try next key if not correct code
bsf LED_PORT, LED3 ;turn on LED
call LED_5sec ;5 seconds logic 1
bcf LED_PORT, LED3 ;turn off LED
bcf Flags2, New ;and cancel new flag
retlw 0x00
Key4 movlw But5 ;test for button 1
subwf Cmd_Byte, w
btfss STATUS, Z
goto Key5 ;try next key if not correct code
bsf LED_PORT, LED4 ;turn on LED
call LED_5sec ;5 seconds logic 1
bcf LED_PORT,LED4 ;turn off LED
bcf Flags2, New ;and cancel new flag
retlw 0x00
Key5 movlw But6 ;test for button 1
subwf Cmd_Byte, w
btfss STATUS, Z
goto Key6 ;try next key if not correct code
bsf LED_PORT,LED5 ;turn on LED
call LED_5sec ;5 seconds logic 1
bcf LED_PORT, LED5 ;turn off LED
bcf Flags2, New ;and cancel new flag
retlw 0x00
Key6 movlw But7 ;test for button 1
subwf Cmd_Byte, w
btfss STATUS, Z
goto Key7 ;try next key if not correct code
bsf LED_PORT, LED6 ;turn on LED
btfsc tmp3, LED6
bcf LED_PORT, LED6 ;turn off LED
bcf Flags2, New ;and cancel new flag
retlw 0x00
Key7 movlw But8 ;test for button 1
subwf Cmd_Byte, w
btfss STATUS, Z
retlw 0X00
bsf LED_PORT, LED7 ;turn on LED
call LED_5sec ;5 seconds logic 1
bcf LED_PORT, LED7 ;turn off LED
bcf Flags2, New ;and cancel new flag
retlw 0x00
;IR routines
ReadIR
call Read_Pulse ;this loop will only ever progress
btfss Flags, StartFlag ;with setting of startflag
goto ReadIR ;wait for start pulse (2.4mS)
Get_Data movlw 0x07 ;set up to read 7 bits
movwf Bit_Cntr
clrf Cmd_Byte
Next_RcvBit2
call Read_Pulse
btfsc Flags, StartFlag ;abort if another Start bit
goto ReadIR
btfsc Flags, ErrFlag ;abort if error
goto ReadIR
bcf STATUS, C
btfss Flags, Zero
bsf STATUS, C
rrf Cmd_Byte, f
decfsz Bit_Cntr, f
goto Next_RcvBit2
rrf Cmd_Byte, f ;correct bit alignment for 7 bits
Get_Cmd movlw 0x05 ;set up to read 5 bits
movwf Bit_Cntr
clrf Dev_Byte
Next_RcvBit call Read_Pulse
btfsc Flags, StartFlag ;abort if another Start bit
goto ReadIR
btfsc Flags, ErrFlag ;abort if error
goto ReadIR
bcf STATUS, C
btfss Flags, Zero
bsf STATUS, C
rrf Dev_Byte, f
decfsz Bit_Cntr, f
goto Next_RcvBit
rrf Dev_Byte, f ;correct bit alignment for 5 bits
rrf Dev_Byte, f
rrf Dev_Byte, f
retlw 0x00
;end of ReadIR
;read pulse width, return flag for StartFlag, One, Zero, or ErrFlag
;output from IR receiver is normally high, and goes low when signal received
Read_Pulse clrf LoX
btfss IR_PORT, IR_In ;wait until high
goto $-1
clrf tmp1
movlw 0xC0 ;delay to decide new keypress
movwf tmp2 ;for keys that need to toggle
Still_High btfss IR_PORT, IR_In ;and wait until goes low
goto Next
incfsz tmp1,f
goto Still_High
incfsz tmp2,f
goto Still_High
bsf Flags2, New ;set New flag if no button pressed
goto Still_High
Next nop
nop
nop
nop
nop ;waste time to scale pulse
nop ;width to 8 bits
nop
nop
nop
nop
nop
nop
incf LoX,f
btfss IR_PORT, IR_In
goto Next ;loop until input high again
; test if Zero, One, or Start (or error)
Chk_Pulse clrf Flags
TryError movf LoX, w ; check if pulse too small
addlw d'255' - d'20' ; if LoX <= 20
btfsc STATUS, C
goto TryZero
bsf Flags, ErrFlag ; Error found, set flag
retlw 0x00
TryZero movf LoX, w ; check if zero
addlw d'255' - d'60' ; if LoX <= 60
btfsc STATUS, C
goto TryOne
bsf Flags, Zero ; Zero found, set flag
retlw 0x00
TryOne movf LoX, w ; check if one
addlw d'255' - d'112' ; if LoX <= 112
btfsc STATUS, C
goto TryStart
bsf Flags, One ; One found, set flag
retlw 0x00
TryStart movf LoX, w ; check if start
addlw d'255' - d'180' ; if LoX <= 180
btfsc STATUS , C
goto NoMatch
bsf Flags, StartFlag ; Start pulse found
retlw 0x00
NoMatch ; pulse too long
bsf Flags, ErrFlag ; Error found, set flag
retlw 0x00
;end of pulse measuring routines
;Delay routines
Delay255 movlw 0xff ;delay 255 mS
goto d0
Delay100 movlw d'100' ;delay 100mS
goto d0
Delay50 movlw d'50' ;delay 50mS
goto d0
Delay20 movlw d'20' ;delay 20mS
goto d0
Delay5 movlw 0x05 ;delay 5.000 ms (4 MHz clock)
d0 movwf count1
d1 movlw 0xC7
movwf counta
movlw 0x01
movwf countb
Delay_0 decfsz counta, f
goto $+2
decfsz countb, f
goto Delay_0
decfsz count1 ,f
goto d1
retlw 0x00
;end of Delay routines
;5 second timeloop routine
LED_5sec
call Delay255 ;uses existing 255ms delay
decfsz Mark20,f ;has this happened 20 times
goto LED_5sec ;to create a 5 second delay?
movlw d'20'
movwf Mark20
retlw 0x00
;end of 5 second on led delay routine
end
