46 lines
1.4 KiB
NASM
Executable File
46 lines
1.4 KiB
NASM
Executable File
LIST P=18F4550, F=INHX32 ; Specify processor and hex format
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#include <p18f4550.inc>
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CONFIG FOSC = HS ; Use internal oscillator, RA6 as clock output
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;CONFIG FOSC = XT_XT ; Use internal oscillator, RA6 as clock output
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CONFIG WDT = OFF ; Watchdog Timer off
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CONFIG LVP = OFF ; Low-Voltage Programming off
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CONFIG MCLRE = OFF ; MCLR pin disabled, RE3 input enabled
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R1 EQU 0x020
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R2 EQU 0x021
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ORG 0x00 ; Program starts at address 0
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Start:
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; Initialize PORTB
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CLRF TRISD ; Set all PORTB pins as output
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CLRF LATD ; Clear PORTB outputs
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Loop:
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call Delay ; Delay
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; RLCF PORTD, F
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MOVLW 0x15
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MOVWF PORTD
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CALL Delay ; Delay
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MOVLW 0x00
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MOVWF PORTD
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goto Loop ; Repeat the loop
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; Delay subroutine (approx 500ms)
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Delay:
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MOVLW D'250' ; Outer loop count
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MOVWF R1
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Delay_Outer:
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MOVLW D'250' ; Inner loop count
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MOVWF R2
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Delay_Inner:
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NOP ; Do nothing (No Operation)
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NOP
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DECFSZ R2, F ; Decrement inner loop counter
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GOTO Delay_Inner ; Repeat inner loop
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DECFSZ R1, F ; Decrement outer loop counter
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GOTO Delay_Outer ; Repeat outer loop
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RETURN ; Return from delay
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END ; End of program
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