Here are some PIC assembly codes I have compiled over the years. If you'd like some explanation of how these codes work, check out my tutorials page.
Beginner:
Blink One LED
Toggle the state of RA0.
; Blink LED Example
; Simple LED blinking program for PIC16F84A
; LED connected to RA0, blinks every 500ms
list p=16f84a
include <p16f84a.inc>
; Configuration bits
__CONFIG _FOSC_HS & _WDTE_OFF & _PWRTE_ON & _CP_OFF
; Variables
cblock 0x20
delay1
delay2
endc
org 0x00
goto start
org 0x04
; Interrupt vector (not used in this example)
retfie
start:
; Set RA0 as output
bsf STATUS, RP0 ; Select Bank 1
bcf TRISA, 0 ; Set RA0 as output
bcf STATUS, RP0 ; Select Bank 0
; Main loop
main_loop:
bsf PORTA, 0 ; Turn LED on
call delay_500ms ; Wait 500ms
bcf PORTA, 0 ; Turn LED off
call delay_500ms ; Wait 500ms
goto main_loop ; Repeat
delay_500ms:
; 500ms delay at 4MHz crystal
movlw 0x82
movwf delay1
movlw 0x7A
movwf delay2
delay_loop:
decfsz delay1, f
goto delay_loop
decfsz delay2, f
goto delay_loop
return
end
Blink All LED
All pins of PORTB simultaneously turn on and then turn off on a loop.
; Blink LED Example
; Simple LED blinking program for PIC16F84A
; LED connected to PORTB pins, blinks every 200ms
list p=16f84a
include <p16f84a.inc>
; Configuration bits
__CONFIG _FOSC_HS & _WDTE_OFF & _PWRTE_ON & _CP_OFF
; Variables
cblock 0x20
delay1
delay2
endc
org 0x00
goto start
org 0x04
; Interrupt vector (not used in this example)
retfie
start:
; Set RA0 as output
bsf STATUS, RP0 ; Select Bank 1
movlw 0x00
movwf TRISB ; Make all PORTB pins output
bcf STATUS, RP0 ; Select Bank 0
; Main loop
main_loop:
movlw 0xFF
movwf PORTB ; Make all PORTB pins high
call delay_500ms ; Wait 500ms
movlw 0x00
movwf PORTB ; Make all PORTB pins low
call delay_500ms ; Wait 500ms
goto main_loop ; Repeat
delay_500ms:
; 500ms delay at 4MHz crystal
movlw 0x82
movwf delay1
movlw 0x7A
movwf delay2
delay_loop:
decfsz delay1, f
goto delay_loop
decfsz delay2, f
goto delay_loop
return
end
Using a Switch
A switch is connected normally high at RA0. If the switch is pressed, RB0 is pulled low, otherwise, RB0 stays high.
list p=16f84a
include <p16f84a.inc>
; Configuration bits
__CONFIG _FOSC_HS & _WDTE_OFF & _PWRTE_ON & _CP_OFF
; Variables
cblock 0x20
delay1
delay2
endc
org 0x00
start
start:
bsf STATUS,RP0 ;bank 1
movlw 0x01
movwf TRISA ;make all PORTA output except RA0
movlw 0x00
movwf TRISB ;make all PORTB output
bcf STATUS,RP0 ;bank 0
main_loop:
btfss PORTA,0 ;check RA0 if high, if it is, skip the next line
goto sub1 ;program goes here if RA0 is low
bcf PORTB,0 ;program goes here if RA0 is high; make RBO low
call delay_loop ;delay subroutine
goto main_loop
sub1:
bsf PORTB,0 ;make RB0 high
call delay_loop
goto main_loop
delay_loop:
loop1 decfsz delay1,1 ;decrement COUNT1 variable until zero
goto delay_loop
decfsz delay2,1 ;decrement COUNT2, if not zero, go back to loop1
goto delay_loop
return
end
Count Button Press (w/ Seven Segment Display):
Display on a common cathode seven segment display the number of button presses on RA0. If the number of presses exceeds nine, the counter goes back to zero.
list p=16f84a
include <p16f84a.inc>
; bit order: 0b0gfedcba
; RB0=a, RB1=b, RB2=c, RB3=d, RB4=e, RB5=f, RB6=g
; Configuration bits
__CONFIG _FOSC_HS & _WDTE_OFF & _PWRTE_ON & _CP_OFF
; Variables
cblock 0x20
delay1
delay2
endc
org 0x00
goto start
start:
bsf STATUS, 5 ;goto bank 1
movlw 0x00 ;clear TRISB - set all PORTB as output
movwf TRISB
movlw 0x1F ;set all PORTA as input
movwf TRISA
bcf STATUS, 5 ;goto bank 0
clrf PORTB ; initialize PORTB to 0
main_loop:
btfsc PORTA,0 ; check if RA0 button is pressed
goto main_loop ; if not pressed, go back to main_loop
call delay ; debounce
call delay
call delay
btfsc PORTA,0 ; check again
goto main_loop ; if not pressed, go back to main_loop
; Check current display pattern and move to next digit
movf PORTB, W
xorlw b'00000000' ; blank / initial state
btfsc STATUS, Z
goto show_0
movf PORTB, W
xorlw b'00111111' ; currently 0
btfsc STATUS, Z
goto show_1
movf PORTB, W
xorlw b'00000110' ; currently 1
btfsc STATUS, Z
goto show_2
movf PORTB, W
xorlw b'01011011' ; currently 2
btfsc STATUS, Z
goto show_3
movf PORTB, W
xorlw b'01001111' ; currently 3
btfsc STATUS, Z
goto show_4
movf PORTB, W
xorlw b'01100110' ; currently 4
btfsc STATUS, Z
goto show_5
movf PORTB, W
xorlw b'01101101' ; currently 5
btfsc STATUS, Z
goto show_6
movf PORTB, W
xorlw b'01111101' ; currently 6
btfsc STATUS, Z
goto show_7
movf PORTB, W
xorlw b'00000111' ; currently 7
btfsc STATUS, Z
goto show_8
movf PORTB, W
xorlw b'01111111' ; currently 8
btfsc STATUS, Z
goto show_9
movf PORTB, W
xorlw b'01101111' ; currently 9
btfsc STATUS, Z
goto show_0
goto show_0 ; fallback if PORTB has unknown value
show_0:
movlw b'00111111'
movwf PORTB
goto wait_release
show_1:
movlw b'00000110'
movwf PORTB
goto wait_release
show_2:
movlw b'01011011'
movwf PORTB
goto wait_release
show_3:
movlw b'01001111'
movwf PORTB
goto wait_release
show_4:
movlw b'01100110'
movwf PORTB
goto wait_release
show_5:
movlw b'01101101'
movwf PORTB
goto wait_release
show_6:
movlw b'01111101'
movwf PORTB
goto wait_release
show_7:
movlw b'00000111'
movwf PORTB
goto wait_release
show_8:
movlw b'01111111'
movwf PORTB
goto wait_release
show_9:
movlw b'01101111'
movwf PORTB
goto wait_release
wait_release:
btfss PORTA,0 ; wait until button is released
goto wait_release
call delay ; debounce release
call delay
goto main_loop
delay:
loop1 decfsz delay1,1 ;decrement COUNT1 variable until zero
goto loop1
decfsz delay2,1 ;decrement COUNT2, if not zero, go back to loop1
goto loop1
return
end
Intermediate
Timer Interrupt
Strobe lights from RB7 to RB0 and back using timer overflow interrupt.
list p=16f84a
include <p16f84a.inc>
; Variables
cblock 0x20
COUNT1
COUNT2
W_T
ST_T
endc
org 0x00
goto start
org 0x04
goto isr
start:
bsf STATUS, RP0 ; Switch to Bank 1
movlw 0x00
movwf TRISA ; PORTA all output
movlw 0x00
movwf TRISB ; PORTB all output
movlw 07h
movwf OPTION_REG ; Timer0 internal clock, prescaler assigned to TMR0, 1:256
bcf STATUS, RP0 ; Switch to Bank 0
bcf INTCON,T0IF ; Clear Timer0 overflow flag first
bsf INTCON,GIE ; Enable all interrupts
bsf INTCON,T0IE ; Enable timer overflow interrupt
movlw 0x80
movwf PORTB
goto main
;---------------interrupt handler
isr:
bcf INTCON,GIE ;Disable interrupt inside handler
movwf W_T ; Save W and STATUS reg inside the ISR
swapf STATUS,W
movwf ST_T
btfss INTCON,T0IF
goto isr_done
bcf STATUS,C ; clear Carry first
btfsc PORTB,0 ; check if RB0 is 1
bsf STATUS,C ; if yes, wrap it back to RB7
rrf PORTB,1 ; rotate PORTB right
bcf INTCON,T0IF ; clear Timer0 overflow flag
isr_done:
swapf ST_T,W
movwf STATUS
swapf W_T, 1
swapf W_T,W
bsf INTCON,GIE ;Re-enable interrupts
retfie
;---------------main routine
main:
goto main
;---------------delay subroutine
delay:
movlw d'255'
movwf COUNT1
movlw d'255'
movwf COUNT2
loop1:
decfsz COUNT1,1
goto loop1
decfsz COUNT2,1
goto loop1
return
end
RBO Interrupt:
Turn off blinking when RB0 is pressed.
list p=16f84a
include <p16f84a.inc>
cblock 0x20
COUNT1
COUNT2
endc
org 0x00
goto start
org 0x04
goto isr
start:
bsf STATUS, RP0 ; bank 1
movlw 0x00
movwf TRISA ; make all PORTA output
movlw 0x01
movwf TRISB ; make all PORTB output except RB0
bcf STATUS, RP0 ; bank 0
movlw b'10010000'
movwf INTCON ; enable GIE, INTE
goto main
;-----------interrupt handler
isr:
bcf INTCON, GIE ; disable all interrupt inside handler
bcf PORTA,0 ; make RA0 low
call delay ; multiple calls to delay for longer pause
call delay
call delay
bcf INTCON,INTF ; clear the interrupt flag
bsf INTCON, GIE ; enable interrupt
retfie
;-----------main routine
main:
call delay
bsf PORTA,0 ;make RA0 high
call delay
bcf PORTA,0 ;make RA0 low
call delay
goto main
;-----------delay subroutine
delay:
loop1 decfsz COUNT1,1
goto loop1
decfsz COUNT2,1
goto loop1
return
end
RB Change Interrupt:
Similar to the code above except interrupt is triggered when changes to RB4, RB5, RB6 or RB7 is made.
list p=16f84a
include <p16f84a.inc>
cblock 0x20
COUNT1
COUNT2
endc
org 0x00
goto start
org 0x04
goto isr
start:
bsf STATUS, RP0 ; bank 1
movlw 0x00
movwf TRISA ; make all PORTA output
movlw 0x01
movwf TRISB ; make all PORTB output except RB0
bcf STATUS, RP0 ; bank 0
movlw b'10001000'
movwf INTCON ; enable GIE, RBIE
goto main
;-----------interrupt handler
isr:
bcf INTCON, GIE ; disable all interrupt inside handler
bcf PORTA,0 ; make RA0 low
call delay ; multiple calls to delay for longer pause
call delay
call delay
bcf INTCON, RBIF ; clear the interrupt flag
bsf INTCON, GIE ; enable interrupt
retfie
;-----------main routine
main:
call delay
bsf PORTA,0 ; make RA0 high
call delay
bcf PORTA,0 ; make RA0 low
call delay
goto main
;-----------delay subroutine
delay:
loop1 decfsz COUNT1,1
goto loop1
decfsz COUNT2,1
goto loop1
return
end
EEPROM Write Interrupt:
Triggers an interrupt when the data to EEPROM has been written.
list p=16f84a
include <p16f84a.inc>
org 0x00
goto start
org 0x04
goto isr
start:
bsf STATUS, RP0 ; Bank 1
clrf TRISA
bsf EECON1, WREN ; Enable Write
; this is a required sequence according to the datasheet
movlw 55h
movwf EECON2 ; Write 55h
movlw AAh ;
movwf EECON2 ; Write AAh
bsf EECON1,WR ; Set WR bit
; end of required sequence
bcf STATUS, RP0 ; Bank 0
bcf PORTA,0 ;clear RA0
movlw 0FFh ;write 0FFh to EEDATA
movwf EEDATA
movlw b'11000000' ;enable EEPROM write interrupt
movwf INTCON
goto main
;-----------interrupt handler
isr:
bcf INTCON, GIE
bcf INTCON, EEIE
bsf PORTA,0
bsf INTCON, EEIE
bsf INTCON, GIE
retfie
end
PWM:
Generate hardware PWM at RB3 using PIC16F628A.
list p=16F628A
include <p16f628a.inc>
cblock 0x20
COUNT1
COUNT2
endc
org 0x00
goto init
init:
movlw .50
movwf COUNT1
movwf COUNT2
;-------SET PWM FREQUENCY
bsf STATUS, RP0 ; Bank 1
movlw .64 ; Set PR2 to 64 decimal; PWM frequency = 961 Hz at 4 MHz
movwf PR2
bcf STATUS, RP0 ; Bank 0
movlw .32 ; Set PWM starting duty cycle to 50%
movwf CCPR1L
movlw b'00101100'
movwf CCP1CON
bsf STATUS, RP0 ; Bank 1
bcf TRISB, 3 ; Set RB3 as output for PWM
bcf STATUS, RP0 ; Bank 0
movlw b'00000010' ; Set Timer2 prescale value to 16
; so the PWM period = 2064uS => PWM frequency = 484Hz
movwf T2CON
clrf TMR2 ; Clear Timer2 module
bsf T2CON, TMR2ON ; Enable Timer2 module
main:
call delay
goto main
delay:
loop1 decfsz COUNT1,1
goto loop1
decfsz COUNT2,1
goto loop1
return
end
Advanced
USART Communication:
Send "!" character to serial port.
list p = 16F628A
include <p16f628a.inc>
cblock 0x20
char0
COUNT1
COUNT2
endc
org 0x00
goto init
init:
clrf PORTB
clrf PORTA
bsf STATUS, RP0 ; Bank 1
clrf TRISB ; all PORTB pins are output
movlw 01h
movwf TRISA ; make all PORTA pins output except RA0
movlw 07h
movwf CMCON ; disable comparator modules
;---CONFIGURE SPBRG FOR DESIRED BAUD RATE
movlw d'25' ; baud rate = 9600bps
movwf SPBRG ; at 4MHZ
;---CONFIGURE TXSTA
movlw b'00100100'
movwf TXSTA
; Configures TXSTA as 8 bit transmission, transmit enabled, async mode, high speed baud rate
bcf STATUS, RP0 ; Bank 0
movlw b'10000000'
movwf RCSTA ; Enable serial port receive
movlw 0x21
movwf char0 ; Put ! (ascii code 21) character to char0 register
main:
btfsc PORTA, 0 ; Check if button at RA0 is pressed
goto main ; If not, wait
; Else transmit a byte
movf char0, W
movwf TXREG ; Place the ! character to TXREG
goto wthere
call delay
goto main
wthere:
btfss TXSTA, TRMT ; Check if TRMT is empty
goto wthere ; If not, check again
bcf STATUS, RP0 ; Bank 0, if TRMT is empty then the character has been sent
return
delay:
loop1 decfsz COUNT1,1
goto loop1
decfsz COUNT2,1
goto loop1
return
end
USART - Display a Rabbit:
list p = 16F628A
include <p16f628a.inc>
cblock 0x20
charOpPa
charClPa
charBlash
charSlash
charUnSc
charEq
charSQ
charDQ
charPrd
spc
lf
COUNT1
COUNT2
endc
org 0x00
goto init
init:
clrf PORTB
clrf PORTA
bsf STATUS, RP0 ;bank 1
clrf TRISB ;all PORTB pins are output
movlw 01h
movwf TRISA ;make all PORTA pins output except RA0
movlw 07h
movwf CMCON ;disable comparator modules
;---CONFIGURE SPBRG FOR DESIRED BAUD RATE
movlw D'25' ;baud rate = 9600bps
movwf SPBRG ;at 4MHZ
;---CONFIGURE TXSTA
movlw B'00100100'
movwf TXSTA
;Configures TXSTA as 8 bit transmission, transmit enabled, async mode, high speed baud rate
bcf STATUS, RP0 ;bank 0
movlw B'10000000'
movwf RCSTA ;enable serial port receive
movlw .40 ;(
movwf charOpPa
movlw .41 ;)
movwf charClPa
movlw .92 ;\
movwf charBlash
movlw .47 ;/
movwf charSlash
movlw .95 ;_
movwf charUnSc
movlw .61 ;=
movwf charEq
movlw .39 ;'
movwf charSQ
movlw .34
movwf charDQ
movlw .46 ;.
movwf charPrd
movlw .32
movwf spc
movlw .13
movwf lf
main:
btfsc PORTA, 0 ;check if button at RA0 is pressed
goto main ;if not, wait
;else transmit a byte
;------------line1
movf spc, W
movwf TXREG ;TO TXREG
call wthere
movf spc, W
movwf TXREG ;TO TXREG
call wthere
movf charOpPa, W
movwf TXREG ;TO TXREG
call wthere
movf charBlash, W
movwf TXREG ;TO TXREG
call wthere
movf charUnSc, W
movwf TXREG ;TO TXREG
call wthere
movf charUnSc, W
movwf TXREG ;TO TXREG
call wthere
movf charUnSc, W
movwf TXREG ;TO TXREG
call wthere
movf charSlash, W
movwf TXREG ;TO TXREG
call wthere
movf charClPa, W
movwf TXREG
call wthere
movf lf, W ;line feed
movwf TXREG ;TO TXREG
call wthere
;-------------line2
movf spc, W
movwf TXREG ;TO TXREG
call wthere
movf spc, W
movwf TXREG ;TO TXREG
call wthere
movf charOpPa, W
movwf TXREG ;TO TXREG
call wthere
movf charEq, W
movwf TXREG ;TO TXREG
call wthere
movf charSQ, W
movwf TXREG ;TO TXREG
call wthere
movf charPrd, W
movwf TXREG ;TO TXREG
call wthere
movf charSQ, W
movwf TXREG ;TO TXREG
call wthere
movf charEq, W
movwf TXREG ;TO TXREG
call wthere
movf charClPa, W
movwf TXREG
call wthere
movlw .13 ;line feed
movwf TXREG ;TO TXREG
call wthere
;------------line3
movf spc, W
movwf TXREG ;TO TXREG
call wthere
movf spc, W
movwf TXREG ;TO TXREG
call wthere
movf charOpPa, W
movwf TXREG ;TO TXREG
call wthere
movf charDQ, W
movwf TXREG ;TO TXREG
call wthere
movf charClPa, W
movwf TXREG ;TO TXREG
call wthere
movf charUnSc, W
movwf TXREG ;TO TXREG
call wthere
movf charOpPa, W
movwf TXREG ;TO TXREG
call wthere
movf charDQ, W
movwf TXREG ;TO TXREG
call wthere
movf charClPa, W
movwf TXREG ;TO TXREG
call wthere
movlw .13 ;line feed
movwf TXREG ;TO TXREG
call wthere
call delay
goto last
wthere:
loop22 bsf STATUS,RP0
btfss TXSTA, TRMT ;check if TRMT is empty
goto loop22 ;if not, check again
bcf STATUS, RP0
return
delay:
loop1 decfsz COUNT1,1
goto loop1
decfsz COUNT2,1
goto loop1
return
last nop ;so that the display will stay
nop
sleep
end
Using Parallel LCD:
Displays HELLO on a parallel LCD (16x2). Data pins are connected to PORTB. E=RA2, RW=RA1, RS=RA0
list p=16f84a
include <p16f84a.inc>
cblock 0x0c
TEMP
TEMP2
DADDR
COUNT1
COUNT2
CHAR1
CHAR2
CHAR3
CHAR4
CHAR5
CHAR_COUNT
endc
LCD_DATA equ 0x06 ; LCD_DATA wired to PORTB
org 0x00
goto init
init:
movlw 0x05
movwf CHAR_COUNT
movlw 0x48 ;H
movwf CHAR1
movlw 0x45 ;E
movwf CHAR2
movlw 0x4C ;L
movwf CHAR3
movlw 0x4C ;L
movwf CHAR4
movlw 0x4F ;O
movwf CHAR5
bsf STATUS, RP0
clrf TRISB
clrf TRISA
bcf STATUS, RP0
call LCD_prep
call delay
movlw 0x80
call LCD_cmd
call delay
main:
call LCD_sendchr
goto end_here
LCD_sendchr:
movf CHAR1, W
call send_it
movf CHAR2, W
call send_it
movf CHAR3, W
call send_it
movf CHAR4, W
call send_it
movf CHAR5, W
call send_it
return
send_it:
call delay
call LCD_putch
call delay
return
LCD_poll:
bsf STATUS, RP0
clrf TRISB
comf TRISB, F
bcf STATUS, RP0
bcf PORTA, 0
bsf PORTA, 1
bsf PORTA, 2
movf LCD_DATA, W
movwf TEMP2
nop
bcf PORTA, 2
btfsc TEMP2,7
goto LCD_poll
bsf STATUS, RP0
clrf TRISB
bcf STATUS, RP0
return
LCD_cmd:
movwf TEMP
call LCD_poll
bcf PORTA, 0
bcf PORTA, 1
bsf PORTA, 2
movf TEMP, W
movwf LCD_DATA
nop
bcf PORTA, 2
return
LCD_prep:
clrf PORTA
movlw 0x3C ;Configure to 2 x 40, 8-bit mode
call LCD_cmd
movlw 0x0F ;Turn on display and cursor
call LCD_cmd
movlw 0x14 ;Shift cursor right
call LCD_cmd
movlw 0x01 ;clear cursor and return to home position
call LCD_cmd
return
get_DDRAM:
bsf STATUS, RP0
clrf TRISB
comf TRISB, F
bcf STATUS, RP0
bcf PORTA, 0
bsf PORTA, 1
bsf PORTA, 2
movf LCD_DATA, W
nop
bcf PORTA, 2
movwf DADDR
return
LCD_putch:
movwf TEMP
call LCD_poll
movf TEMP,W
bsf PORTA, 0
bcf PORTA, 1
bsf PORTA, 2
movwf LCD_DATA
nop
bcf PORTA, 2
return
chk_0x53:
movlw 0x53
subwf DADDR, F
btfsc STATUS,Z
goto chk_0x27
movlw 0x94 ;Set DDRAM address to 0x14 (start of 3rd line)
call LCD_cmd
call LCD_poll
movf TEMP,W
bsf PORTA, 0
bcf PORTA, 1
bsf PORTA, 2
movwf LCD_DATA
nop
bcf PORTA, 2
return
chk_0x27:
movlw 0x27
subwf DADDR, F
btfsc STATUS,Z
return
movlw 0xD4
call LCD_cmd
call LCD_poll
movf TEMP, W
bsf PORTA, 0
bcf PORTA, 1
bsf PORTA, 2
movwf LCD_DATA
nop
bcf PORTA, 2
return
delay:
loop1 decfsz COUNT1,1
goto loop1
decfsz COUNT2,1
goto loop1
return
end_here:
nop
nop
end
Dual Seven Segment w/ Lookup:
Uses persistence of vision (POV) to digits on a dual seven segment display.
list p=16f84a
include <p16f84a.inc>
cblock 0x20
COUNT1
COUNT2
endc
org 0x00
goto start
start:
bsf STATUS,5
movlw 0x00
movwf TRISA
movlw 0x00
movwf TRISB
bcf STATUS,5
movlw .100
movwf COUNT1
movwf COUNT2
main:
movlw 0x02
movwf PORTA
movlw 0x00
call table
movwf PORTB
call delay
movlw 0x01
movwf PORTA
movlw 0x00
call table
movwf PORTB
call delay
call delay
call delay
call delay
movlw 0x02
movwf PORTA
movlw 0x00
call table
movwf PORTB
call delay
movlw 0x01
movwf PORTA
movlw 0x01
call table
movwf PORTB
call delay
call delay
call delay
call delay
movlw 0x02
movwf PORTA
movlw 0x00
call table
movwf PORTB
call delay
movlw 0x01
movwf PORTA
movlw 0x02
call table
movwf PORTB
call delay
call delay
call delay
call delay
movlw 0x02
movwf PORTA
movlw 0x00
call table
movwf PORTB
call delay
movlw 0x01
movwf PORTA
movlw 0x03
call table
movwf PORTB
call delay
call delay
call delay
call delay
movlw 0x02
movwf PORTA
movlw 0x00
call table
movwf PORTB
call delay
movlw 0x01
movwf PORTA
movlw 0x04
call table
movwf PORTB
call delay
call delay
call delay
call delay
movlw 0x02
movwf PORTA
movlw 0x00
call table
movwf PORTB
call delay
movlw 0x01
movwf PORTA
movlw 0x05
call table
movwf PORTB
call delay
call delay
call delay
call delay
movlw 0x02
movwf PORTA
movlw 0x00
call table
movwf PORTB
call delay
movlw 0x01
movwf PORTA
movlw 0x06
call table
movwf PORTB
call delay
call delay
call delay
call delay
movlw 0x02
movwf PORTA
movlw 0x00
call table
movwf PORTB
call delay
movlw 0x01
movwf PORTA
movlw 0x07
call table
movwf PORTB
call delay
call delay
call delay
call delay
movlw 0x02
movwf PORTA
movlw 0x00
call table
movwf PORTB
call delay
movlw 0x01
movwf PORTA
movlw 0x08
call table
movwf PORTB
call delay
call delay
call delay
call delay
movlw 0x02
movwf PORTA
movlw 0x00
call table
movwf PORTB
call delay
movlw 0x01
movwf PORTA
movlw 0x09
call table
movwf PORTB
call delay
call delay
call delay
call delay
goto main
delay:
loop1 decfsz COUNT1,1
goto loop1
decfsz COUNT2,1
goto loop1
return
table:
addwf PC,F
retlw b'00111111' ;digit 0
retlw b'00000110' ;digit 1
retlw b'01011011' ;digit 2
retlw b'01001111' ;digit 3
retlw b'01100110' ;digit 4
retlw b'01101101' ;digit 5
retlw b'01111101' ;digit 6
retlw b'00000111' ;digit 7
retlw b'01111111' ;digit 8
retlw b'01101111' ;digit 9
end
