1011.c

这是5按键读U盘MP3的程序.采用ATmega32芯片.

#include <iom32v.h>
#include <macros.h>
#define uchar unsigned char
#define uint unsigned int
#define MP3_DDR        DDRB
#define MP3_PORT       PORTB
#define MP3_PIN        PINB
#define MP3_CMD_CS     BIT(0)
#define MP3_DATA_CS    BIT(3)
#define MP3_DATA_REQ   BIT(2)   
#define MP3_DATA_REST  BIT(1)  

//SPI initialize
// clock rate: 500000hz
void spi_init(void)
{
 DDRB=0xB0;
 SPCR = 0x53; //setup SPI
 SPSR = 0x00; //setup SPI
}
void mp3_port_init()
{
spi_init();
MP3_DDR|=MP3_DATA_CS |MP3_CMD_CS|MP3_DATA_REST;
MP3_DDR&=~MP3_DATA_REQ;
MP3_PORT|=MP3_DATA_CS |MP3_CMD_CS|MP3_DATA_REST;
}
void Write_Byte_MMC(unsigned char byte)
{   
    SPDR = byte;
    while (!(SPSR & (1<<SPIF)));
}
unsigned char Read_Byte_MMC(void)
{   
    SPDR = 0xFF;
    while (!(SPSR &(1<<SPIF)));
    return SPDR;
}

void vs1011_cmd_write(uchar address,uint data)
{ 
//MP3_PORT|=MP3_DATA_CS;       //MP3_DATA_CS=1;
MP3_PORT&=~MP3_CMD_CS;       //MP3_CMD_CS=0;
Write_Byte_MMC(0x02);      //VS1011的写命令
//delay_nus(20);
Write_Byte_MMC(address);   //地址
Write_Byte_MMC(data>>8);
Write_Byte_MMC(data);
//delay_nus(200);
MP3_PORT|=MP3_CMD_CS;       //MP3_CMD_CS=1;
} 

void vs1011_data_write(uchar data)
{
MP3_PORT&=~MP3_DATA_CS;         //MP3_DATA_CS=0;
Write_Byte_MMC(data);
MP3_PORT|=MP3_DATA_CS;         //MP3_DATA_CS=1;
//MP3_PORT|=MP3_CMD_CS;         //MP3_CMD_CS=1; 
}

uint vs1011_read(uchar address)
{
uchar temp1=0;
uint temp=0; 
//MP3_PORT|=MP3_DATA_CS;        //MP3_DATA_CS=1;
MP3_PORT&=~MP3_CMD_CS;        //MP3_CMD_CS=0;
Write_Byte_MMC(0x03);      //VS1011的读命令
//delay_nus(20);
Write_Byte_MMC(address);   //地址
temp=Read_Byte_MMC();
temp=temp<<8;
temp1=Read_Byte_MMC();
temp=temp|temp1; 
MP3_PORT|=MP3_CMD_CS;       //MP3_CMD_CS=1;
return temp;

}

void vs1011_init(void)
{

vs1011_cmd_write(0x00,0x0800);     //NEW MODE
vs1011_cmd_write(0x02,0X75);   //BASS
vs1011_cmd_write(0x03,0X9800);   //CLOCK F
vs1011_cmd_write(0x0b,0X2020);  //VOLUME
}