RDA5820和51单片机制作的FM数字收音机源代码及电路原理图.doc

*  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 int
typedef 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 * 100KHz
const uint MaxFreq   = 1080;  //最高频率 * 100KHz
const 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0~0xF
uchar 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); 
  }
  Mute = 0;
  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;
 Delay(50);
 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;
 do
 {
  str[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。
 uint reg5H;
 uint tempTune = 0;
 for(i=0;i<ChannelCount;i++)   //清除原有的电台数据
 {               
  ChannelTune[i]=0;
 }
 reg5H = FM_ReadReg(0×05);
 reg5H = (reg5H & 0x80FF) | (seekth<<7);
 FM_WriteReg(0×05,reg5H);
 for(i=0;i<=MaxFreq – MinFreq;i++)
 { 
  FreqTune = i;
  FM_SetFreq();
  Lcd_DispFreq();
  do
  {
   state = FM_ReadReg(0x0B);
   cmp = (state>>  7  ) & 0×1;
  }while(!cmp);
  Delay(100);
  state = FM_ReadReg(0x0B);
  cmp = (state >>   8  ) & 0×1;
  if(cmp)
  {
   ChannelTune[count]=i; 
   count++;
  }
  if(count>=ChannelCount){ break; }
 }
}
uchar FM_GetRSSI()
{
 uint regVal =FM_ReadReg(0x0b); 
 regVal = regVal>>9;

 return (uchar)(regVal/16);
}
void Delay(uint c)
{
 int i=0;
 for(i=0;i<c;i++);
}
uint IICRead(uchar uaddr, uchar ramAddr,bit _16b)
{
 uint buf;
 OpenIIC();
 IICWriteByte(uaddr);
 IICWriteByte(ramAddr);
 OpenIIC();
 IICWriteByte(uaddr | 0×01);

 if(_16b)
 {
  buf = IICReadByte(1);
  buf = buf<<8;
  buf =buf | IICReadByte(0);
 }
 else
 {
  buf = IICReadByte(0);
 }
 CloseIIC();
 return buf;
}
uchar IICReadByte(bit next)
{
 uchar buf =0,i=0;
 for(i=0;i<8;i++)
 { 
  buf <<=1;
  SCL = 1;
  buf |= SDA;
  Delay(5);
  SCL = 0;
  Delay(5); 
 }
 if(next)
 {
  SDA = 0;
  SCL = 1;
  Delay(5);
  SCL = 0;
  Delay(5);
  SDA = 1;
 }
 else
 {
  SDA = 1;
  SCL = 1;
  Delay(5);
  SCL = 0;
  Delay(5); 
  SDA=0;
 }
 return buf;
}
void IICWrite(uchar uaddr, uchar romaddr, uint rdata,bit _16b)
{
   uchar temp;
 OpenIIC();
 IICWriteByte(uaddr);
 IICWriteByte(romaddr);       

 if(_16b)
 {
  temp =(uchar)((rdata>>8) & 0x00ff) ;
  IICWriteByte(temp);
 }
 temp = (uchar) (rdata & 0xff);
 IICWriteByte(temp); 
 CloseIIC();
}
void IICWriteByte( uchar byte )
{
 uchar i=0; 
 int f=30000;      
 bit bitdata;
 for(i=0;i<8;i++)
 {
    bitdata =byte>>(7-i) & 1;
    SDA = bitdata;
    SCL =1;
    Delay(5);
    SCL = 0;
    Delay(5);
 }
 SCL = 1;
 while(SDA && –f);
 Delay(5);
 SCL = 0;
 Delay(5);
}
void CloseIIC()
{
 SDA = 0 ;
 SCL = 1;
 Delay(5);
 SDA = 1;
 Delay(5);
 SCL = 1;
 SDA = 1;
 Delay(150); //防止过快的读取造成EPPROM 来不及反应
}
void OpenIIC()
{
 SDA = 1;
 SCL = 1;
 Delay(5);
 SDA = 0;
 Delay(5);
 SCL = 0;
 Delay(5);
}
/****************************************************************************************************************/