SpiMaster.h

Go to the documentation of this file.

#ifndef _SPIMASTER_H
#define _SPIMASTER_H
#include <stdint.h>
#include "ReadWriteBits.h"
#include "Spi.h"
 
#ifdef USE_FAKES
#include "Spi_faked.h"
/* #include "SpiMaster_faked.h" // no need for this yet */
#endif
 
// ---Private---
//
// ---API (Go to the Doxygen documentation of this file)---
inline uint8_t SpiMasterXfrByte(uint8_t byte)
{
    // select the SPI Slave
    ClearBit(Spi_PortOutput, Spi_Ss);
 
    // load data reg with byte to send
    *Spi_SPDR = byte;
 
    // wait for SPI transmission to complete
    while(BitIsClear(Spi_SPSR, Spi_InterruptFlag));
 
    // unselect the SPI Slave
    SetBit(Spi_PortOutput, Spi_Ss);
 
    // Clear the Spi_InterruptFlag by
    // reading Spi_InterruptFlag while it is set
    // then reading Spi_SPDR
    return *Spi_SPDR;
}
 
// ---API functions that call fakes when testing---
//
#ifdef USE_FAKES
#define ClearSpiInterruptFlag ClearSpiInterruptFlag_fake
#endif
inline void SpiMasterInit(void)
{
    // Pin Ss: HIGH
    SetBit(Spi_PortOutput, Spi_Ss);
    // Pin Ss: output
    SetBit(Spi_PortDirection, Spi_Ss);
 
    // Pin Miso: input
    ClearBit(Spi_PortDirection, Spi_Miso);
    // Pin Miso: enable pullup
    SetBit(Spi_PortOutput, Spi_Miso);
 
    // Pin DataReady: input
    ClearBit(Spi_PortDirection, Spi_DataReady);
    // Pin DataReady: enable pullup
    SetBit(Spi_PortOutput, Spi_DataReady);
 
    // Pin Mosi: output
    SetBit(Spi_PortDirection, Spi_Mosi);
 
    // Pin Sck: output
    SetBit(Spi_PortDirection, Spi_Sck);
 
    // Be the SPI Master
    SetBit(Spi_SPCR, Spi_MasterSlaveSelect);
 
    // Set SPI clock to 1.25MHz
    SetBit  (Spi_SPCR, Spi_ClockBit0);
    ClearBit(Spi_SPCR, Spi_ClockBit1);
    SetBit  (Spi_SPSR, Spi_DoubleClock);
 
    _EnableSpiModule();
 
    ClearSpiInterruptFlag();
}
#ifdef USE_FAKES
#undef ClearSpiInterruptFlag
#endif
 
#endif // _SPIMASTER_H