spi.h

实现了avr下对sd卡的读写,支持文件存取,删除的功能

//-------------------------------------------------------------------------
// SPI interface initializer
void spiInit(void);
//-------------------------------------------------------------------------
// spiTransferByte(uint8_t data) waits until the SPI interface is ready
// and then sends a single byte over the SPI port.  The function also
// returns the byte that was received during transmission.
uint8_t spiTransferByte(uint8_t data);
//-------------------------------------------------------------------------