timer.s

单片机中的定时器模块

	.module timer.c
	.area text(rom, con, rel)
	.dbfile F:\芯生光盘资料\范例代码\TIMER\prj\timer\timer.c
	.dbfunc e timer0_init _timer0_init fV
	.even
_timer0_init::
	.dbline -1
	.dbline 16
; 
; #include <macros.h>
; #include "stdtypes.h"
; #include "timer.h"
; 
; 
; 
; UNS8 time_couter;
; 
; 
; //TIMER0 initialize - prescale:64
; // WGM: Normal
; // desired value: 1mSec
; // actual value:  0.998mSec (0.2%)
; void timer0_init(void)
; {
	.dbline 17
;  TCCR0 = 0x00; //stop
	clr R2
	out 0x33,R2
	.dbline 18
;  ASSR  = 0x00; //set async mode
	out 0x30,R2
	.dbline 19
;  TCNT0 = SET_COUNT; //set count
	ldi R24,141
	out 0x32,R24
	.dbline 20
;  TCCR0 = 0x07; //start timer
	ldi R24,7
	out 0x33,R24
	.dbline 21
;  TIMSK = TIMSK | (1 << TOIE0);
	in R24,0x37
	ori R24,1
	out 0x37,R24
	.dbline 23
;  
;  time_couter=0;
	sts _time_couter,R2
	.dbline -2
L1:
	.dbline 0 ; func end
	ret
	.dbend
	.area vector(rom, abs)
	.org 64
	jmp _timer0_ovf_isr
	.area text(rom, con, rel)
	.dbfile F:\芯生光盘资料\范例代码\TIMER\prj\timer\timer.c
	.dbfunc e timer0_ovf_isr _timer0_ovf_isr fV
	.even
_timer0_ovf_isr::
	st -y,R2
	st -y,R24
	st -y,R25
	in R2,0x3f
	st -y,R2
	.dbline -1
	.dbline 28
; }
; 
; #pragma interrupt_handler timer0_ovf_isr:17
; void timer0_ovf_isr(void)
; {
	.dbline 31
;  //CLI(); //disable all interrupts
;  
;  TCNT0 = SET_COUNT;
	ldi R24,141
	out 0x32,R24
	.dbline 35
; /*read the key value*/
; 
;   
; 	 if(time_couter>10)
	ldi R24,10
	lds R2,_time_couter
	cp R24,R2
	brsh L3
	.dbline 36
; 	 {
	.dbline 37
; 	   time_couter=0;
	clr R2
	sts _time_couter,R2
	.dbline 38
; 	 }
	xjmp L4
L3:
	.dbline 40
	.dbline 41
	lds R24,_time_couter
	subi R24,255    ; addi 1
	sts _time_couter,R24
	.dbline 42
L4:
	.dbline -2
L2:
	ld R2,y+
	out 0x3f,R2
	ld R25,y+
	ld R24,y+
	ld R2,y+
	.dbline 0 ; func end
	reti
	.dbend
	.area bss(ram, con, rel)
	.dbfile F:\芯生光盘资料\范例代码\TIMER\prj\timer\timer.c
_time_couter::
	.blkb 1
	.dbsym e time_couter _time_couter c