RDA5820和51单片机制作的FM数字收音机源代码及电路原理图

* 晶振:8M*/#include <reg52.h>#include <string.h>#define ChannelCount 50 //最多支持多少个台，因为常驻内存，多了RAM放不下#define uchar unsigned char#define uint unsigned inttypedef struct{uchar Freq;uchar Rssi;}ChannelInfo;sbit SDA = P2^0;sbit SCL = P2^1;sbit key1 = P3^4;sbit key2 = P2^7;sbit key3 = P2^6;sbit key4 = P2^5; // P3^7;sbit LcdEn = P3^4;sbit LcdRs = P3^5;uchar Channel = 0;uchar FreqTune = 0;const uint MinFreq = 870; //起始频率* 100KHzconst uint MaxFreq = 1080; //最高频率* 100KHzconst uchar FmAddr = 0×22; //FM模块IIC 地址const uchar EpAddr = 0xA0; //24C02 EPPRom 的地址uchar RSSI = 0; //信号强度uchar ChannelTune[ChannelCount];uchar code LevlChar[5][8] ={{0x1F,0×11,0x0A,0×04,0×04,0×04,0×04,0×04},{0×00,0×00,0×00,0×00,0×00,0×00,0×06,0x1E},{0×00,0×00,0×00,0×00,0×06,0x1E,0x1E,0x1E}, //显示型号强度的自定义字符{0×00,0×00,0×06,0x1E,0x1E,0x1E,0x1E,0x1E},{0×06,0x1E,0x1E,0x1E,0x1E,0x1E,0x1E,0x1E}};uchar vol = 0×8; //音量0~0xFuchar Func = 0×0; //当前功能号bit AutoScan = 0; //标记当前是不是在自动搜台bit Mute = 0; //标记是否被静音uchar KeyNumber = 0;void OpenIIC();void CloseIIC();void IICWrite(uchar uaddr, uchar romaddr, uint rdata,bit _i6b);void IICWriteByte( uchar byte );uint IICRead(uchar uaddr, uchar romaddr,bit _i6b);uchar IICReadByte(bit next);void FM_SetFreq();void FM_SetVolume();uint FM_ReadReg(uchar regAddr); //读取FM模块的寄存器void FM_WriteReg(uchar regAddr,uint dat); //写FM模块的寄存器uchar FM_GetRSSI(); //获取当前的信号强大void Delay(uint c);bit KeyScan();void BeginScan();void Lcd_DispNumber(uint number);void Lcd_Init();void Lcd_Comm(uchar cmd);void Lcd_Data(uchar dat);void Lcd_String(char* dat);void Lcd_DispRssi();void Lcd_DispFreq();void Lcd_Refresh();void Lcd_DispDiscript();void Eprom_LoadInitData();uint Eprom_Read(uchar addr,bit _16bit);void Eprom_Write(uchar addr,uint dat,bit _16bit);void main(){P3 = 0xff;P2 = 0xff;Delay(10000); //延时，等待外部FM模块的启动Eprom_LoadInitData(); //从EppRom 加载频道音量等信息 FM_WriteReg(2,0xd281); //启动FM模块FM_SetVolume(); //设置启动音量FM_SetFreq(); //设置默认频道的频率Lcd_Init();Lcd_Refresh();while(1){if( KeyScan()){Lcd_Refresh();}}}void Eprom_LoadInitData(){uint result = 0;int i=0;result =Eprom_Read(0,0);if(result>0){ vol = (uchar)result –1;}result =Eprom_Read(1,0);Channel = (uchar)result;for(i=0;i<ChannelCount;i++){result =Eprom_Read(i * 2 + 2,1);ChannelTune[i] = result;}FreqTune = ChannelTune[Channel];}void Eprom_Write(uchar addr,uint dat,bit _16bit) {IICWrite(EpAddr,addr,dat,_16bit);}uint Eprom_Read(uchar addr,bit _16bit){return IICRead(EpAddr,addr,_16bit);}uint FM_ReadReg(uchar regAddr){return IICRead(FmAddr,regAddr,1);}void FM_WriteReg(uchar regAddr,uint dat) {IICWrite(FmAddr,regAddr,dat,1);}void FM_SetFreq(){FM_WriteReg(3,(FreqTune<<6) | 0×10);}void FM_SetVolume(){uint reg2H;if(vol>0){if(Mute){reg2H = FM_ReadReg(2);reg2H |= 0×4000;FM_WriteReg(2,reg2H);}FM_WriteReg(5,vol);}else{Mute = 1;reg2H = FM_ReadReg(2);reg2H &= 0xBFFF;FM_WriteReg(2,reg2H);}Eprom_Write(0,vol+1,0);}void Lcd_Init(){uchar CGRamAddr = 0×40;int i,j;LcdEn = 0;Lcd_Comm(0×38);Lcd_Comm(0x0c);Lcd_Comm(0×06);Lcd_Comm(0×01);for(j=0;j<5;j++){Lcd_Comm(CGRamAddr + 8 * j); //建立自定义字符(显示信号强度的) for(i=0;i<8;i++){Lcd_Data(LevlChar[j][i]);Delay(510);}}}void Lcd_Comm(uchar cmd){LcdRs =0;P0 = cmd;Delay(50);LcdEn = 1;Delay(50);LcdEn = 0;}void Lcd_Data(uchar dat){LcdRs = 1;P0 = dat;LcdEn = 1;Delay(50);LcdEn = 0;}void Lcd_String(char* dat){char *p;int j, i=strlen(dat);for(j=0;j<i;j++){p=dat + j;Lcd_Data(*p);}}void Lcd_DispRssi(){int i;Lcd_Comm(0×80);for(i=0;i<5;i++){Lcd_Data(‘‘);}RSSI = FM_GetRSSI();Lcd_Comm(0×80);Lcd_Data(0×00);if(RSSI>=1) Lcd_Data(0×01);if(RSSI>=2) Lcd_Data(0×02);if(RSSI>=3) Lcd_Data(0×03);if(RSSI>=4) Lcd_Data(0×04);}void Lcd_DispFreq(){uint curFreq = MinFreq + FreqTune;int i;Lcd_Comm(0×85);for(i=5;i<16;i++){Lcd_Data(‘‘);}Lcd_Comm(0×80+6);if(curFreq>=1000)Lcd_Data(48 +curFreq /1000 % 10); Lcd_Data(48 +curFreq /100 % 10);Lcd_Data(48 +curFreq /10 % 10);Lcd_Data(‘.’);Lcd_Data(48 + curFreq % 10);Lcd_Data(‘M’);Lcd_Data(‘H’);Lcd_Data(‘Z’);}void Lcd_DispDiscript(){int i;Lcd_Comm(0×80+0×40);for(i=0;i<15;i++){Lcd_Data(‘‘);}Lcd_Comm(0×80+0×40);switch(Func){case 0:Lcd_String(“Channel:”);Lcd_DispNumber(Channel+1);break;case 1:Lcd_String(“Volume:”);Lcd_DispNumber(vol);break;case 2:Lcd_String(“Tune”);break;case 3:Lcd_String(“Auto Scan”);}}void Lcd_Refresh(){Lcd_DispRssi();Lcd_DispFreq();Lcd_DispDiscript();}void Lcd_DispNumber(uint number){int i=0,len;char str[6]={‘\0′,’\0′,’\0′,’\0′,’\0′,’\0′}; char temp;dostr[i++] = ’0′+ (number % 10); number /= 10;}while(number) ;len = strlen(str);for(i=0;i<len/2;i++){temp = str[i];str[i] = str[len-i-1];str[len-i-1] = temp;}Lcd_String(str);}bit KeyScan(){bit keyRel = 0; //按键释放检测char value=0;int i;uint temp;if(AutoScan) return 0;if(KeyNumber==0){if(key3==0){Delay(50);if(key3==0){KeyNumber =3;}}if(key4==0){Delay(50);if(key4==0){KeyNumber=4;}}if(key2==0){Delay(50);if(key2==0)KeyNumber=2;}}return 0;}else{switch(KeyNumber){case 1:if(key1==1)keyRel = 1; break;case 2:if(key2==1)keyRel = 1; break;case 3:if(key3==1)keyRel = 1; break;case 4:if(key4==1)keyRel = 1; break;}if(keyRel){switch(KeyNumber){case 2:Func++;if(Func>3) Func = 0;break;case 3:value = -1;break;case 4:value = 1;break;}if(KeyNumber>2){if(Func==0){if((value > 0 && Channel<ChannelCount) || (value<0 && Channel > 0)) {Channel+=value;FreqTune= ChannelTune[Channel];FM_SetFreq();Eprom_Write(1,Channel, 0);}else if(Func==1){if((value > 0 && vol<0xF) || (value<0 && vol > 0)){vol+=value;FM_SetVolume();}}else if(Func==2){if((value > 0 && FreqTune<0xd2) || (value<0 && FreqTune > 0)) {FreqTune+=value;ChannelTune[Channel] = FreqTune;FM_SetFreq();Eprom_Write(Channel * 2 + 2 ,FreqTune,1);}}else if(Func==3) //开始自动扫描{AutoScan = 1;BeginScan();AutoScan = 0;Channel = 0;FreqTune = ChannelTune[0];Func = 0;FM_SetFreq();//覆盖EppRom中的所有的频道for(i=0;i<ChannelCount;i++){temp = ChannelTune[i];Eprom_Write(i * 2+2,temp,1);}Eprom_Write(0×01,0,0); //重置EPPROM中的频道号为0}}KeyNumber=0;}return keyRel;}}//全自动搜索void BeginScan(){uint state;int i=0,count=0;bit cmp = 0;uint seekth = 0×8; //灵敏度0~127,默认为8 灵敏度越低越可能搜索到假台，高了可能一些信号弱一点的频道被跳过。