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[tdm]

Nguyên văn bởi tuan1007

Với đoạn chương trình sau mình muốn RB0 nháy 257 lần thì đặc vòng lặp như thế nào ?
Cảm ơn các bạn trước nha!

title "chop led _b.asm"
processor p16f877a
include <p16f877a.inc>
__CONFIG _CP_OFF&_PWRTE_ON&_WDT_OFF&_HS_OSC&_LVP_OFF
;----------------------------------------------------------------------------
count_1 equ 0x20
count_2 equ 0x21
ORG 0x0000
GOTO MAIN


MAIN
ORG 0X0005
BANKSEL TRISB
CLRF TRISB
BANKSEL PORTB

LOOP clrf PORTB
CALL DELAY
MOVLW h'01'
MOVWF PORTB
CALL DELAY
GOTO LOOP
;--------------------------------------------------------------------------
;CHUONG TRINH DELAY

DELAY CLRF count_1
D2 CLRF count_2
D1 DECFSZ count_2
GOTO D1
DECFSZ count_1
GOTO D2
return


END

**************************************************

title "chop led _b.asm"
processor p16f877a
include <p16f877a.inc>
__CONFIG _CP_OFF&_PWRTE_ON&_WDT_OFF&_HS_OSC&_LVP_OFF
;----------------------------------------------------------------------------
count_1 equ 0x20
count_2 equ 0x21
count_3 equ 0x22
ORG 0x0000
GOTO MAIN
MAIN
ORG 0X0005
BANKSEL TRISB
CLRF TRISB
BANKSEL PORTB
CLRF count_3
LOOP clrf PORTB
CALL DELAY
MOVLW h'01'
MOVWF PORTB
CALL DELAY
DECFSZ count_3,1;VONG LAP
GOTO LOOP
clrf PORTB
CALL DELAY
MOVLW h'01'
MOVWF PORTB
CALL DELAY
GOTO $
;--------------------------------------------------------------------------
;CHUONG TRINH DELAY

DELAY CLRF count_1
D2 CLRF count_2
D1 DECFSZ count_2,1
GOTO D1
DECFSZ count_1,1
GOTO D2
return
END[/quote]