51读写SD卡，为何不能初始化？

1万 · 2010-4-22 20:43

MCU=89C52,晶振=12MHZ
/**************************************************************
函数原型：void ini_sd(void)
功能：上电后初始化SD卡
**************************************************************/
bit Ini_sd(void)
{
  uchar temp=0,temp1=0;
bit bdata  state=1;
sd_cs=1;
delay_1s();
Write_delay();
sd_cs=0;
do{
temp= Write_cmd(cmd0,0x00000000,0x4a);    //发送CMD0
}while(temp!=0x01);
sd_cs=1;
Write_byte(0xff);
led_0=0;
do{
  sd_cs=0;
  while(Write_cmd(cmd55,0x00000000,0x32)!=0x01); ////发送CMD55
  sd_cs=1;
  Write_byte(0xff);
  led_1=0;
  sd_cs=0;
  temp1=Write_cmd(cmd41,0x00000000,0xff);    //程序死在这里
  sd_cs=1;
}while(temp1!=0x00);
sd_cs=1;
Write_byte(0xff);
led_2=0;
state=0;