C8051F020产生方波正弦波三角波

//----------------------------------------------------------------------------- // 程序描述： // BTF020 针对C8051F020单片机(SOC)设计的BT F020开发评估板 // 本程序是利用020的DA0口输出正弦波、三角波、矩形波 // 其中KEY1为正弦波KEY2为三角波,KEY3为矩形波，KEY4为频率增加 // 并在LCD上显示出来(注:J18要短接给LCD供电). //作者:哈尔滨工程大学 信息与通信工程学院 杨蕊 王琢 //时间:2008-12-16 //版本:V1.0 //注：早上没事，做个思维训练，利用了开发板内带的各种例程简单的拼凑除了这个程序涉及到的D/A程序、key程序、LCD程序， // 调试已通过。但没有优化，只为给初学者做练习！ //----------------------------------------------------------------------------- #include <C8051F020.H> // SFR declarations //----------------------------------------------------------------------------- // 16-bit SFR Definitions for 'F02x //----------------------------------------------------------------------------- sfr16 RCAP4 = 0xe4; // Timer4 capture/reload sfr16 T4 = 0xf4; // Timer4 sfr16 DAC0 = 0xd2; // DAC0 data #define SYSCLK 16000000 void Timer4_Init (int counts); void Timer4_ISR (void); void SYSCLK_Init (void); unsigned long x; unsigned char da_count=0; //正弦函数表 来自例程DTMF 十六进制 char xdata sine_table[100] = { 0x80,0x88,0x90,0x97,0x9f,0xa7,0xaf,0xb6,0xbd,0xc4, 0xcb,0xd1,0xd7,0xdd,0xe2,0xe7,0xec,0xf0,0xf3,0xf6, 0xf9,0xfb,0xfd,0xfe,0xff,0xff,0xff,0xff,0xfd,0xfc, 0xf9,0xf7,0xf3,0xf0,0xec,0xe7,0xe2,0xdd,0xd7,0xd1, 0xcb,0xc4,0xbd,0xb6,0xaf,0xa7,0xa0,0x98,0x90,0x88, 0x80,0x78,0x70,0x68,0x60,0x58,0x51,0x49,0x42,0x3b, 0x34,0x2e,0x28,0x22,0x1d,0x18,0x14,0x0f,0x0c,0x09, 0x06,0x04,0x02,0x01,0x00,0x00,0x00,0x00,0x02,0x03, 0x06,0x08,0x0c,0x0f,0x13,0x18,0x1d,0x22,0x28,0x2e, 0x34,0x3b,0x42,0x49,0x50,0x58,0x5f,0x67,0x6f,0x77 }; //三角函数表 十进制 char xdata tri_table[256] = { 0,2,4,6,8,10,12,14,16,18,20,22,24,26,28,30, 32,34,36,38,40 ,42 ,44 ,46 ,48 ,50 ,52 ,54 ,56 ,58 ,60 ,62 ,64 ,66 , 68,70,72,74,76 ,78 ,80 ,82 ,84 ,86 ,88 ,90 ,92 ,94 ,96 ,98 ,100,102, 104,106,108,110,112,114,116,118,120,122,124,126,128,130,132,134,136,138, 140,142,144,146,148,150,152,154,156,158,160,162,164,166,168,170,172,174, 176,178,180,182,184,186,188,190,192,194,196,198,200,202,204,206,208,210, 212,214,216,218,220,222,224,226,228,230,232,234,236,238,240,242,244,246, 248,250,252,254,252,250,248,246,244,242,240,238,236,234,232,230,228,226, 224,222,220,218,216,214,212,210,208,206,204,202,200,198,196,194,192,190, 188,186,184,182,180,178,176,174,172,170,168,166,164,162,160,158,156,154, 152,150,148,146,144,142,140,138,136,134,132,130,128,126,124,122,120,118, 116,114,112,110,108,106,104,102,100,98,96,94,92,90,88,86,84,82,80,78,76, 74,72,70,68,66,64,62,60,58,56,54,52,50,48,46,44,42,40,38,36,34,32,30,28, 26,24,22,20,18,16,14,12,10,8,6,4,2,0 }; //矩形波函数表 十进制 char xdata squ_table[256] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,255,255,255,255,255,255,255,255, 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, 255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255, 255,255,255,255,255,255 }; //----------------------------------------------------------------------------- // Timer4_Init //----------------------------------------------------------------------------- // void Timer4_Init (int counts) { T4CON = 0; CKCON |= 0x40;//定时器使用系统时钟 RCAP4 = -counts;//重装值 T4 = RCAP4; EIE2 |= 0x04;//允许定时器4中断 EA = 1; T4CON |= 0x04;//定时器4运行 } //----------------------------------------------------------------------------- // Timer4_ISR //----------------------------------------------------------------------------- // void Timer4_ISR (void) interrupt 16 using 3 { T4CON &= ~0x80;//清零标志位,必须软件清零 //DAC0H = tri_table[da_count];//输出三角波 DAC0H =sine_table[da_count]; //0x80^sine_table[da_count];//正弦波 //DAC0H =squ_table[da_count];//方波 da_count++; if(da_count==99) { da_count=0; } } void SYSCLK_Init (void) { int i; // 延时计数器 OSCXCN = 0x67; // 启动外部振荡器16MHz晶体 for (i=0; i < 256; i++) ; // 等待振荡器启动 while (!(OSCXCN & 0x80)) ; // 等待振荡器稳定 OSCICN = 0x88; // 选择外部振荡器为时钟源并使能丢失时钟检测器 } void PORT_Init (void) { XBR0 = 0x00; XBR1 = 0x00; XBR2 = 0x40; // 使能数据交叉开关和弱上拉 //P74OUT |= 0xff; // 使能为推挽输出 } void main(void) { WDTCN = 0xde; WDTCN = 0xad; SYSCLK_Init (); // 初始化振荡器 PORT_Init (); // 初始化数据交叉开关和通用IO口 REF0CN = 0x03;// 使能内部VREF发生器 DAC0CN = 0x97;//DAC0允许，DAC输出更新发生在定时器4溢出时，DAC0数据格式为左对齐 Timer4_Init(SYSCLK/100000); // 初始化T4为DAC0定时更新 while(1); }