main.s

一个关于AVR单片机的例程

	.module main.c
	.area text(rom, con, rel)
	.dbfile E:\avr\2.2.2\main.c
	.dbfunc e port_init _port_init fV
	.even
_port_init::
	.dbline -1
	.dbline 11
; //ICC-AVR application builder : 2007-6-9 0:33:58
; // Target : M16
; // Crystal: 1.0000Mhz
; // 用途：演示定时器的工作原理
; // 作者：古欣
; // AVR与虚拟仪器 http://www.avrvi.com
; #include <iom16v.h>
; #include <macros.h>
; 
; void port_init(void)
; {
	.dbline 12
;  PORTA = 0x00;
	clr R2
	out 0x1b,R2
	.dbline 13
;  DDRA  = 0x03; //PA0 PA1 输出
	ldi R24,3
	out 0x1a,R24
	.dbline 14
;  PORTB = 0x00;
	out 0x18,R2
	.dbline 15
;  DDRB  = 0xFF; //PB 输出
	ldi R24,255
	out 0x17,R24
	.dbline 16
;  PORTC = 0x00; //m103 output only
	out 0x15,R2
	.dbline 17
;  DDRC  = 0x00;
	out 0x14,R2
	.dbline 18
;  PORTD = 0x00;
	out 0x12,R2
	.dbline 19
;  DDRD  = 0x00;
	out 0x11,R2
	.dbline -2
L1:
	.dbline 0 ; func end
	ret
	.dbend
	.dbfunc e timer0_init _timer0_init fV
	.even
_timer0_init::
	.dbline -1
	.dbline 27
; }
; 
; //TIMER0 initialize - prescale:8
; // WGM: Normal
; // desired value: 1KHz
; // actual value:  1.000KHz (0.0%)
; void timer0_init(void)
; {
	.dbline 28
;  TCCR0 = 0x00; //stop
	clr R2
	out 0x33,R2
	.dbline 29
;  TCNT0 = 0x83; //set count
	ldi R24,131
	out 0x32,R24
	.dbline 30
;  OCR0  = 0x7D;  //set compare
	ldi R24,125
	out 0x3c,R24
	.dbline 31
;  TCCR0 = 0x02; //start timer
	ldi R24,2
	out 0x33,R24
	.dbline -2
L2:
	.dbline 0 ; func end
	ret
	.dbend
	.area vector(rom, abs)
	.org 76
	jmp _timer0_comp_isr
	.area text(rom, con, rel)
	.dbfile E:\avr\2.2.2\main.c
	.dbfunc e timer0_comp_isr _timer0_comp_isr fV
	.even
_timer0_comp_isr::
	st -y,R2
	st -y,R24
	in R2,0x3f
	st -y,R2
	.dbline -1
	.dbline 37
; }
; 
; //比较匹配中断
; #pragma interrupt_handler timer0_comp_isr:20
; void timer0_comp_isr(void)
; {
	.dbline 39
;  //compare occured TCNT0=OCR0
;  if(OCR0==0x7D) //调整0x7D
	in R24,0x3c
	cpi R24,125
	brne L4
	.dbline 40
;  {
	.dbline 41
;   OCR0=0x7F;
	ldi R24,127
	out 0x3c,R24
	.dbline 42
;  }
	xjmp L5
L4:
	.dbline 44
;  else
;  {
	.dbline 45
;   OCR0=0x7D;
	ldi R24,125
	out 0x3c,R24
	.dbline 46
;  }
L5:
	.dbline 47
;   PORTA ^= 0x01; //PA0取反
	ldi R24,1
	in R2,0x1b
	eor R2,R24
	out 0x1b,R2
	.dbline -2
L3:
	ld R2,y+
	out 0x3f,R2
	ld R24,y+
	ld R2,y+
	.dbline 0 ; func end
	reti
	.dbend
	.area vector(rom, abs)
	.org 36
	jmp _timer0_ovf_isr
	.area text(rom, con, rel)
	.dbfile E:\avr\2.2.2\main.c
	.dbfunc e timer0_ovf_isr _timer0_ovf_isr fV
	.even
_timer0_ovf_isr::
	st -y,R2
	st -y,R24
	in R2,0x3f
	st -y,R2
	.dbline -1
	.dbline 53
; }
; 
; //溢出中断中断
; #pragma interrupt_handler timer0_ovf_isr:10
; void timer0_ovf_isr(void)
; {
	.dbline 54
;  TCNT0 = 0x83; //reload counter value
	ldi R24,131
	out 0x32,R24
	.dbline 55
;  PORTA ^= 0x01; //PA0取反
	ldi R24,1
	in R2,0x1b
	eor R2,R24
	out 0x1b,R2
	.dbline -2
L6:
	ld R2,y+
	out 0x3f,R2
	ld R24,y+
	ld R2,y+
	.dbline 0 ; func end
	reti
	.dbend
	.dbfunc e init_devices _init_devices fV
	.even
_init_devices::
	.dbline -1
	.dbline 60
; }
; 
; //call this routine to initialize all peripherals
; void init_devices(void)
; {
	.dbline 62
;  //stop errant interrupts until set up
;  CLI(); //disable all interrupts
	cli
	.dbline 63
;  port_init();
	xcall _port_init
	.dbline 64
;  timer0_init();
	xcall _timer0_init
	.dbline 66
; 
;  MCUCR = 0x00;
	clr R2
	out 0x35,R2
	.dbline 67
;  GICR  = 0x00;
	out 0x3b,R2
	.dbline 68
;  TIMSK = 0x03; //timer interrupt sources 允许定时器零匹配和溢出中断
	ldi R24,3
	out 0x39,R24
	.dbline 69
;  SEI(); //re-enable interrupts
	sei
	.dbline -2
L7:
	.dbline 0 ; func end
	ret
	.dbend
	.dbfunc e main _main fV
	.even
_main::
	.dbline -1
	.dbline 74
;  //all peripherals are now initialized
; }
; 
; void main(void)
; {
	.dbline 75
;  init_devices();
	xcall _init_devices
	.dbline 76
;  PORTA=0x00;
	clr R2
	out 0x1b,R2
	xjmp L10
L9:
	.dbline 78
	.dbline 79
	in R2,0x32
	out 0x18,R2
	.dbline 80
L10:
	.dbline 77
	xjmp L9
X0:
	.dbline -2
L8:
	.dbline 0 ; func end
	ret
	.dbend