oc2上输出矩形波.lst

ICC mega8例子

__start:
__text_start:
      13 E5CF      LDI	R28,0x5F
      14 E0D4      LDI	R29,4
      15 BFCD      OUT	0x3D,R28
      16 BFDE      OUT	0x3E,R29
      17 51CE      SUBI	R28,0x1E
      18 40D0      SBCI	R29,0
      19 EA0A      LDI	R16,0xAA
      1A 8308      STD	Y+0,R16
      1B 2400      CLR	R0
      1C E6E0      LDI	R30,0x60
      1D E0F0      LDI	R31,0
      1E E010      LDI	R17,0
      1F 36E0      CPI	R30,0x60
      20 07F1      CPC	R31,R17
      21 F011      BEQ	0x0024
      22 9201      ST	R0,Z+
      23 CFFB      RJMP	0x001F
      24 8300      STD	Z+0,R16
      25 E2E6      LDI	R30,0x26
      26 E0F0      LDI	R31,0
      27 E6A0      LDI	R26,0x60
      28 E0B0      LDI	R27,0
      29 E010      LDI	R17,0
      2A E000      LDI	R16,0
      2B BF0B      OUT	0x3B,R16
      2C 32E6      CPI	R30,0x26
      2D 07F1      CPC	R31,R17
      2E F021      BEQ	0x0033
      2F 95C8      LPM
      30 9631      ADIW	R30,1
      31 920D      ST	R0,X+
      32 CFF9      RJMP	0x002C
      33 D01E      RCALL	_main
_exit:
      34 CFFF      RJMP	_exit
FILE: E:\xiaozhiyong2009\设计资料\项目设计\ICCAVR_mega8_C\ICCAVR_mega8_OC2上输出矩形波\OC2上输出矩形波.c
(0001) //ICC-AVR application builder : 2009-3-11 13:07:26
(0002) // Target : M8
(0003) // Crystal: 8.0000Mhz
(0004) 
(0005) #include <iom8v.h>
(0006) #include <macros.h>
(0007) 
(0008) void port_init(void)
(0009) {
(0010)  PORTB = 0x00;
_port_init:
      35 2422      CLR	R2
      36 BA28      OUT	0x18,R2
(0011)  DDRB  = 0x00;
      37 BA27      OUT	0x17,R2
(0012)  PORTC = 0x00; //m103 output only
      38 BA25      OUT	0x15,R2
(0013)  DDRC  = 0x00;
      39 BA24      OUT	0x14,R2
(0014)  PORTD = 0x00;
      3A BA22      OUT	0x12,R2
(0015)  DDRD  = 0x00;
      3B BA21      OUT	0x11,R2
      3C 9508      RET
(0016) }
(0017) 
(0018) //call this routine to initialize all peripherals
(0019) void init_devices(void)
(0020) {
(0021)  //stop errant interrupts until set up
(0022)  CLI(); //disable all interrupts
_init_devices:
      3D 94F8      BCLR	7
(0023)  port_init();
      3E DFF6      RCALL	_port_init
(0024) 
(0025)  MCUCR = 0x00;
      3F 2422      CLR	R2
      40 BE25      OUT	0x35,R2
(0026)  GICR  = 0x00;
      41 BE2B      OUT	0x3B,R2
(0027)  TIMSK = 0x00; //timer interrupt sources
      42 BE29      OUT	0x39,R2
(0028)  SEI(); //re-enable interrupts
      43 9478      BSET	7
      44 9508      RET
(0029)  //all peripherals are now initialized
(0030) }
(0031) 
(0032) /************************************
(0033) 用    途:TC2用CTC模式输出频率可调矩形波
(0034) Taget   :mega8
(0035) crystal :8M
(0036) 介    绍:初始化以后就可以在OC2上输出矩形波了，
(0037) 	  	 但OC2必须设为输出(PB3)
(0038) 入口参数:p可用来调节频率,为0-255中的一个
(0039) 出口参数:
(0040) *************************************/
(0041) void init_timer2_CTC(unsigned char p)
(0042) {
(0043)  DDRB|=(1<<PB3);
_init_timer2_CTC:
  p                    --> R16
      45 9ABB      SBI	0x17,3
(0044)  TCCR2=0x0;//TC2工作于定时方式，先停止TC2
      46 2422      CLR	R2
      47 BC25      OUT	0x25,R2
(0045)  TCNT2=0x00;//计数器初始值设为0
      48 BC24      OUT	0x24,R2
(0046)  OCR2=p;//设置比较参考值
      49 BD03      OUT	0x23,R16
(0047)  TIMSK|=(1<<OCIE2);//打开TOV2的比较区配中断	
      4A B789      IN	R24,0x39
      4B 6880      ORI	R24,0x80
      4C BF89      OUT	0x39,R24
(0048)  //TC2工作于定时方式CTC（WGM2[1：0]=2）
(0049)  //比较匹配时触发OC2取反(COM2[1:0]=1)
(0050)  //系统时钟256分频(CS2[2:0]=0xC)
(0051)  TCCR2=(1<<WGM21)|(1<<COM20)|(1<<CS22)|(1<<CS21);
      4D E18E      LDI	R24,0x1E
      4E BD85      OUT	0x25,R24
      4F 9508      RET
(0052) }
(0053) //改变频率
(0054) void timer2_CTC(unsigned char x)
(0055) {
(0056)  OCR2=x;
_timer2_CTC:
  x                    --> R16
      50 BD03      OUT	0x23,R16
      51 9508      RET
(0057) }
(0058) 
(0059) void main()
(0060) {
(0061)  port_init();
_main:
      52 DFE2      RCALL	_port_init
(0062)  init_devices();
      53 DFE9      RCALL	_init_devices
(0063)  
(0064)  init_timer2_CTC(20);
      54 E104      LDI	R16,0x14
      55 DFEF      RCALL	_init_timer2_CTC
(0065)  while(1)
FILE: <library>
      56 CFFF      RJMP	0x0056
      57 9508      RET