为什么我把VS1003程序中的音乐数据改为别的歌就播不了了？

void spi_write(uint8 ch);void VS1003init();void wr_commad(unsigned char addr,unsigned char hdat,unsigned char ldat) ;void sintest(unsigned char x) ;void delayms(uint16 z);void delayus(uint16 z);
void main(){int i;VS1003init();XDCS=0;for(i=0;i<20000;i++){DREQ=1;while(!DREQ);spi_write(music);}while(1);}void spi_write(uint8 ch){uint8 i;for(i=0;i<8;i++){MOSI=0x80&ch; //高位先写ch<<=1;SCLK=0; //上升沿有效SCLK=1;}}void wr_commad(unsigned char addr,unsigned char hdat,unsigned char ldat) {     DREQ=1;     while(!DREQ);     XCS=0;    spi_write(0x02);     spi_write(addr);     spi_write(hdat);     spi_write(ldat);     XCS=1; }void VS1003init(){XRST=0;delayus(100);XDCS=XCS=XRST=1;wr_commad(0x00,0x80,0x04);  //VS1003新模式 软件复位delayus(10);DREQ=1;while(!DREQ);wr_commad(0x03,0x98,0x00);  //VS1003时钟：3倍频delayus(10);wr_commad(0x05,0xbb,0x81);  //VS1003采样率：48Kps 立体声delayus(10);wr_commad(0x02,0x00,0x55);  //设置重音delayus(10);wr_commad(0x0b,0x20,0x20);   //设置音量delayus(10);spi_write(0x00); //写4个字节的无效数据以驱动spi_write(0x00);spi_write(0x00);spi_write(0x00);} void sintest(unsigned char x) //正弦测试（循环）{     wr_commad(0x00,0x08,0x20);  //VS1003测试模式    DREQ=1;     while(!DREQ);     XDCS=0;XCS=1;     spi_write(0x53);     spi_write(0xef);     spi_write(0x6e);     spi_write(x);  //频率    spi_write(0);     spi_write(0);     spi_write(0);     spi_write(0);     delayus(5000);     spi_write(0x45);     spi_write(0x78);     spi_write(0x69);     spi_write(0x74);     spi_write(0);     spi_write(0);     spi_write(0);     spi_write(0);     delayus(5000);     XDCS=1; } void delayms(uint16 z){uint16 i,j;for(i=z;i>0;i--)for(j=110;j>0;j--);} void delayus(uint16 z){while(z--);}
这段代码可以播放原先附有的music[](音乐数据)，然后我把这段音乐数据改为别的歌（前面32个字节有在的），为什么就播不了了？帮帮忙哈，太感谢您了