/* 檢測卡是否完全插入  check weather card is insert entirely */
extern INT8U SD_ChkCard(void);

/* 檢測卡是否寫保護  check weather card is write protect */
extern INT8U SD_ChkCardWP(void);

/* 初始化訪問SD卡的硬件初始化 initialize the hardware that access sd card */
extern void SD_HardWareInit(void);

/* 設置SPI的時鐘小于400kHZ set the clock of SPI less than 400kHZ */
extern void SPI_Clk400k(void);

/* 設置SPI的clock到最大值 set the clock of SPI to maximum */
extern void SPI_ClkToMax(void);

/* 通過SPI接口發送一個字節 send a byte by SPI interface */
extern void SPI_SendByte(INT8U byte);

/* 從SPI接口接收一個字節 receive a byte from SPI interface */
extern INT8U SPI_RecByte(void);

/* 片選SPI從機 select the SPI slave */
extern void SPI_CS_Assert(void);

/* 不片選SPI從機 not select the SPI slave */
extern void SPI_CS_Deassert(void);