usci_b_spi.c

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//*****************************************************************************
//
// usci_b_spi.c - Driver for the usci_b_spi Module.
//
//*****************************************************************************
 
//*****************************************************************************
//
//
//*****************************************************************************
 
#include "inc/hw_memmap.h"
 
#ifdef __MSP430_HAS_USCI_Bx__
#include "usci_b_spi.h"
 
#include <assert.h>
 
bool USCI_B_SPI_initMaster(uint16_t baseAddress, USCI_B_SPI_initMasterParam *param)
{
    //Disable the USCI Module
    HWREG8(baseAddress + OFS_UCBxCTL1) |= UCSWRST;
 
    //Reset OFS_UCBxCTL0 values
    HWREG8(baseAddress + OFS_UCBxCTL0) &= ~(UCCKPH + UCCKPL + UC7BIT + UCMSB +
        UCMST + UCMODE_3 + UCSYNC);
 
    //Reset OFS_UCBxCTL1 values
    HWREG8(baseAddress + OFS_UCBxCTL1) &= ~(UCSSEL_3);
 
    //Select Clock
    HWREG8(baseAddress + OFS_UCBxCTL1) |= param->selectClockSource;
 
    HWREG16(baseAddress + OFS_UCBxBRW) =
        (uint16_t)(param->clockSourceFrequency / param->desiredSpiClock);
 
    /*
     * Configure as SPI master mode.
     * Clock phase select, polarity, msb
     * UCMST = Master mode
     * UCSYNC = Synchronous mode
     * UCMODE_0 = 3-pin SPI
     */
    HWREG8(baseAddress + OFS_UCBxCTL0) |= (
        param->msbFirst +
        param->clockPhase +
        param->clockPolarity +
        UCMST +
        UCSYNC +
        UCMODE_0
        );
 
    return ( STATUS_SUCCESS) ;
}
 
void USCI_B_SPI_changeMasterClock(uint16_t baseAddress,
    USCI_B_SPI_changeMasterClockParam *param)
{
    //Disable the USCI Module
    HWREG8(baseAddress + OFS_UCBxCTL1) |= UCSWRST;
 
    HWREG8(baseAddress + OFS_UCBxBRW) =
        (uint16_t)(param->clockSourceFrequency / param->desiredSpiClock);
 
    //Reset the UCSWRST bit to enable the USCI Module
    HWREG8(baseAddress + OFS_UCBxCTL1) &= ~(UCSWRST);
}
bool USCI_B_SPI_initSlave (uint16_t baseAddress,
    uint8_t msbFirst,
    uint8_t clockPhase,
    uint8_t clockPolarity
    )
{
    //Disable USCI Module
    HWREG8(baseAddress + OFS_UCBxCTL1)  |= UCSWRST;
 
    //Reset OFS_UCBxCTL0 register
    HWREG8(baseAddress + OFS_UCBxCTL0) &= ~(UCMSB +
                                            UC7BIT +
                                            UCMST +
                                            UCCKPL +
                                            UCCKPH +
                                            UCMODE_3
                                            );
 
    //Clock polarity, phase select, msbFirst, SYNC, Mode0
    HWREG8(baseAddress + OFS_UCBxCTL0) |= ( clockPhase +
                                            clockPolarity +
                                            msbFirst +
                                            UCSYNC +
                                            UCMODE_0
                                            );
 
    return ( STATUS_SUCCESS) ;
}
 
void USCI_B_SPI_changeClockPhasePolarity (uint16_t baseAddress,
    uint8_t clockPhase,
    uint8_t clockPolarity
    )
{
 
  //Disable the USCI Module
  HWREG8(baseAddress + OFS_UCBxCTL1) |= UCSWRST;
 
  HWREG8(baseAddress + OFS_UCBxCTL0) &= ~(UCCKPH + UCCKPL);
 
  HWREG8(baseAddress + OFS_UCBxCTL0) |= (
        clockPhase +
        clockPolarity
          );
 
  //Reset the UCSWRST bit to enable the USCI Module
  HWREG8(baseAddress + OFS_UCBxCTL1) &= ~(UCSWRST);
}
 
void USCI_B_SPI_transmitData ( uint16_t baseAddress,
    uint8_t transmitData
    )
{
    HWREG8(baseAddress + OFS_UCBxTXBUF) = transmitData;
}
 
uint8_t USCI_B_SPI_receiveData (uint16_t baseAddress)
{
    return ( HWREG8(baseAddress + OFS_UCBxRXBUF)) ;
}
 
void USCI_B_SPI_enableInterrupt (uint16_t baseAddress,
    uint8_t mask
    )
{
    HWREG8(baseAddress + OFS_UCBxIE) |= mask;
}
 
void USCI_B_SPI_disableInterrupt (uint16_t baseAddress,
    uint8_t mask
    )
{
    HWREG8(baseAddress + OFS_UCBxIE) &= ~mask;
}
 
uint8_t USCI_B_SPI_getInterruptStatus (uint16_t baseAddress,
    uint8_t mask
    )
{
    return ( HWREG8(baseAddress + OFS_UCBxIFG) & mask );
}
 
void USCI_B_SPI_clearInterrupt (uint16_t baseAddress,
    uint8_t mask
    )
{
    HWREG8(baseAddress + OFS_UCBxIFG) &=  ~mask;
}
 
void USCI_B_SPI_enable (uint16_t baseAddress)
{
    //Reset the UCSWRST bit to enable the USCI Module
    HWREG8(baseAddress + OFS_UCBxCTL1) &= ~(UCSWRST);
}
 
void USCI_B_SPI_disable (uint16_t baseAddress)
{
    //Set the UCSWRST bit to disable the USCI Module
    HWREG8(baseAddress + OFS_UCBxCTL1) |= UCSWRST;
}
 
uint32_t USCI_B_SPI_getReceiveBufferAddressForDMA (uint16_t baseAddress)
{
    return ( baseAddress + OFS_UCBxRXBUF );
}
 
uint32_t USCI_B_SPI_getTransmitBufferAddressForDMA (uint16_t baseAddress)
{
    return ( baseAddress + OFS_UCBxTXBUF );
}
 
uint8_t USCI_B_SPI_isBusy (uint16_t baseAddress)
{
    //Return the bus busy status.
    return (HWREG8(baseAddress + OFS_UCBxSTAT) & UCBUSY);
}
 
 
#endif
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