main.lst

一个关于AVR单片机的例程

__text_start:
__start:
    002A E5CF      LDI	R28,0x5F
    002B E0D4      LDI	R29,4
    002C BFCD      OUT	0x3D,R28
    002D BFDE      OUT	0x3E,R29
    002E 51C0      SUBI	R28,0x10
    002F 40D0      SBCI	R29,0
    0030 EA0A      LDI	R16,0xAA
    0031 8308      STD	Y+0,R16
    0032 2400      CLR	R0
    0033 E6E0      LDI	R30,0x60
    0034 E0F0      LDI	R31,0
    0035 E010      LDI	R17,0
    0036 36E0      CPI	R30,0x60
    0037 07F1      CPC	R31,R17
    0038 F011      BEQ	0x003B
    0039 9201      ST	R0,Z+
    003A CFFB      RJMP	0x0036
    003B 8300      STD	Z+0,R16
    003C E5E4      LDI	R30,0x54
    003D E0F0      LDI	R31,0
    003E E6A0      LDI	R26,0x60
    003F E0B0      LDI	R27,0
    0040 E010      LDI	R17,0
    0041 35E4      CPI	R30,0x54
    0042 07F1      CPC	R31,R17
    0043 F021      BEQ	0x0048
    0044 95C8      LPM
    0045 9631      ADIW	R30,1
    0046 920D      ST	R0,X+
    0047 CFF9      RJMP	0x0041
    0048 940E0063  CALL	_main
_exit:
    004A CFFF      RJMP	_exit
FILE: E:\avr\2－1－4\main.c
(0001) 
(0002) //ICC-AVR application builder : 2007-1-29 10:04:38
(0003) // Target : M16
(0004) // Crystal: 7.3728Mhz
(0005) // 用途：演示通过PINB读按键的值，赋值给PORTA，键盘扫描模型。
(0006) // 作者：古欣
(0007) // AVR与虚拟仪器 [url]http://www.avrvi.com[/url]
(0008) // 使用7.3728M外部晶振，请短接跳线JP2的1和2，电源跳线连接3.3V或者5V
(0009) // 开发板连接：LED0～3——PA0～3，独立按键A~D接PB0～3
(0010) 
(0011) #include <iom16v.h>
(0012) #include <macros.h>
(0013) 
(0014) #define led_port PORTA
(0015) //定义输出端口
(0016) #define led_ddr DDRA
(0017) //定义输出控制寄存器
(0018) #define key_PORT PORTB
(0019) #define key_DDR DDRB
(0020) 
(0021) 
(0022) 
(0023) void port_init(void)
(0024) {
(0025) PORTA = 0x0F;  //LED灭
_port_init:
    004B E08F      LDI	R24,0xF
    004C BB8B      OUT	0x1B,R24
(0026) DDRA = 0x00;
    004D 2422      CLR	R2
    004E BA2A      OUT	0x1A,R2
(0027) PORTB = 0xFF; //按键的端口为输入
    004F EF8F      LDI	R24,0xFF
    0050 BB88      OUT	0x18,R24
(0028) DDRB = 0x00;
    0051 BA27      OUT	0x17,R2
(0029) PORTC = 0x00; //m103 output only
    0052 BA25      OUT	0x15,R2
(0030) DDRC = 0x00;
    0053 BA24      OUT	0x14,R2
(0031) PORTD = 0x00;
    0054 BA22      OUT	0x12,R2
(0032) DDRD = 0x00;
    0055 BA21      OUT	0x11,R2
(0033) led_ddr=0xff; //设置LED的端口为输出
    0056 BB8A      OUT	0x1A,R24
(0034) key_PORT=0x0F; //使能按键的IO口的内部上拉
    0057 E08F      LDI	R24,0xF
    0058 BB88      OUT	0x18,R24
    0059 9508      RET
(0035) }
(0036) 
(0037) //call this routine to initialize all peripherals
(0038) //此处为ICC系统生成，未做更改
(0039) void init_devices(void)
(0040) {
(0041) //stop errant interrupts until set up
(0042) CLI(); //disable all interrupts
_init_devices:
    005A 94F8      BCLR	7
(0043) port_init();
    005B DFEF      RCALL	_port_init
(0044) 
(0045) MCUCR = 0x00;
    005C 2422      CLR	R2
    005D BE25      OUT	0x35,R2
(0046) GICR = 0x00;
    005E BE2B      OUT	0x3B,R2
(0047) TIMSK = 0x00; //timer interrupt sources
    005F BE29      OUT	0x39,R2
(0048) SEI(); //re-enable interrupts
    0060 9478      BSET	7
    0061 9508      RET
(0049) //all peripherals are now initialized
(0050) }
(0051) 
(0052) void Delay(void) //延时，没有详细计算
(0053) {
(0054) unsigned char i,j;
(0055) /*
(0056) for(i=20;i>0;i--)
(0057) {
(0058) for(j=200;j>0;j--)
(0059) ;
(0060) }
(0061) */
(0062) ;
_Delay:
  j                    --> Y+1
  i                    --> Y+1
    0062 9508      RET
(0063) }
(0064) 
(0065) void main(void)
(0066) {
(0067) unsigned char tmp=0; //定义变量
_main:
  tmp                  --> R20
    0063 2744      CLR	R20
(0068) init_devices();     //初始化
    0064 DFF5      RCALL	_init_devices
    0065 C00D      RJMP	0x0073
(0069) while(1)
(0070) {
(0071)   tmp=(PINB&0x0F); //与0x0F 只取低四位的值
    0066 B346      IN	R20,0x16
    0067 704F      ANDI	R20,0xF
(0072)   if(tmp!=0x0F)
    0068 304F      CPI	R20,0xF
    0069 F041      BEQ	0x0072
(0073)   {
(0074)   Delay();     //延时去抖
    006A DFF7      RCALL	_Delay
(0075)   if((PINB&0x0F)==tmp) //再次读IO口，如果和上次的值相等，则说明确实是键盘按下
    006B B386      IN	R24,0x16
    006C 708F      ANDI	R24,0xF
    006D 1784      CP	R24,R20
    006E F419      BNE	0x0072
(0076)   {
(0077)   PORTA = tmp&0x0F; //将键盘的值输出到PORTA上
    006F 2F84      MOV	R24,R20
    0070 708F      ANDI	R24,0xF
    0071 BB8B      OUT	0x1B,R24
(0078)   }
(0079)   }
(0080) Delay();
FILE: <library>
    0072 DFEF      RCALL	_Delay
    0073 CFF2      RJMP	0x0066
    0074 9508      RET