pwm0.asm

来自「串口通信 频率测量 EEPROM读写程序」· 汇编 代码 · 共 32 行

    ;.include "c:\appnotes\2333def.inc"
         .org $000
          rjmp main
 main:  ldi r17,$df
        out SPL,r17          
        sbi DDRB,1  ;set PB.1 output mode
        ldi r17,$00
        out OCR1H,r17
        ldi r17,$01
        out OCR1L,R17 ; define compare value         
        ldi r18,0b11000001        
        out TCCR1A,r18 ; COM11=1,COM10=1,PWM11=1,PWM10=1 in TCCR1A
                      ;PWM frequency is fosc/510 ,10 byte PWM         
 start: out OCR1L,R17 ; define compare value 
        ldi r18,0b00000001        
        out TCCR1B,r18 ;Timer/Count 1 start to work 
        rcall delay2 
       ; ldi r18,0b00000000        
       ; out TCCR1B,r18 ;Timer/Count 1 stop 
        ; rcall delay2
         inc r17
        rjmp start
 delay2:ldi r21,$01
    d22:ldi r22,$1a                   
    d12:ldi r23,$0ff
    d02:dec r23          
        brne d02            
        dec r22                      
        brne d12
        dec r21         
        brne d22   
         ret