TEA5767的C51控制程序

TEA5767采用I2C或者三线接口控制,我是用的I2C,单片机用STC89C52,带1K EEPROM,可以掉点存台,1602LCD显示,这里只给了TEA5767的控制程序。TEA5767读写数据都是5个字节,其中PLL参数14位,具体数据格式请看datasheet.以下程序中的函数可以直接在主程序中调用。

#include "iic.c"
#define max_freq 108000
#define min_freq 87500
unsigned char radio_write_data[5]={0x29,0xc2,0x20,0x11,0x00};        //要写入TEA5767的数据
unsigned char radio_read_data[5];        //TEA5767读出的状态
unsigned int default_pll=0x29c2;//0x29f9;        //默认存台的pll,87.8MHz
//unsigned int max_pll=0x339b;            //108MHz时的pll,
//unsigned int min_pll=9000;            //70MHz时的pll

void radio_write(void)
{
    unsigned char i;
    iic_start;
    iic_write8bit(2,0xc0);        //TEA5767写地址
    if(!iic_testack)
    {
        for(i=0;i<5;i++)
        {
            iic_write8bit(radio_write_data);
            iic_ack;
        }
    }
    iic_stop(2);    
}

//读TEA5767状态,并转换成频率
void radio_read(void)
{
    unsigned char i;
    unsigned char temp_l,temp_h;
    pll=0;
    iic_start;
    iic_write8bit(0xc1);        //TEA5767读地址
    if(!iic_testack)
    {
        for(i=0;i<5;i++)
        {
            radio_read_data=iic_read8bit();
            iic_ack;
        }
    }
    iic_stop;
    temp_l=radio_read_data[1];
    temp_h=radio_read_data[0];
    temp_h&=0x3f;
    pll=temp_h*256+temp_l;
    get_frequency();
}

//由频率计算PLL
void get_pll(void)
{
    unsigned char hlsi;
    unsigned int twpll=0;
    hlsi=radio_write_data[2]&0x10;
    if (hlsi)
        pll=(unsigned int)((float)((frequency+225)*4)/(float)32.768);    //频率单位:k
    else
        pll=(unsigned int)((float)((frequency-225)*4)/(float)32.768);    //频率单位:k
}
//由PLL计算频率
void get_frequency(void)
{
    unsigned char hlsi;
    unsigned int npll=0;
    npll=pll;
    hlsi=radio_write_data[2]&0x10;
    if (hlsi)
        frequency=(unsigned long)((float)(npll)*(float)8.192-225);    //频率单位:KHz
    else
        frequency=(unsigned long)((float)(npll)*(float)8.192+225);    //频率单位:KHz
}