usci_a_uart.c

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//*****************************************************************************
//
// usci_a_uart.c - Driver for the usci_a_uart Module.
//
//*****************************************************************************
 
//*****************************************************************************
//
//
//*****************************************************************************
 
#include "inc/hw_memmap.h"
 
#ifdef __MSP430_HAS_USCI_Ax__
#include "usci_a_uart.h"
 
#include <assert.h>
 
bool USCI_A_UART_init(uint16_t baseAddress, USCI_A_UART_initParam *param)
{
    bool retVal = STATUS_SUCCESS;
 
    //Disable the USCI Module
    HWREG8(baseAddress + OFS_UCAxCTL1) |= UCSWRST;
 
    //Clock source select
    HWREG8(baseAddress + OFS_UCAxCTL1) &= ~UCSSEL_3;
    HWREG8(baseAddress + OFS_UCAxCTL1) |= param->selectClockSource;
 
    //MSB, LSB select
    HWREG8(baseAddress + OFS_UCAxCTL0) &= ~UCMSB;
    HWREG8(baseAddress + OFS_UCAxCTL0) |= param->msborLsbFirst;
 
 
    //UCSPB = 0(1 stop bit) OR 1(2 stop bits)
    HWREG8(baseAddress + OFS_UCAxCTL0) &= ~UCSPB;
    HWREG8(baseAddress + OFS_UCAxCTL0) |= param->numberofStopBits;
 
 
    //Parity
    switch (param->parity){
        case USCI_A_UART_NO_PARITY:
            //No Parity
            HWREG8(baseAddress + OFS_UCAxCTL0) &= ~UCPEN;
            break;
        case USCI_A_UART_ODD_PARITY:
            //Odd Parity
            HWREG8(baseAddress + OFS_UCAxCTL0) |= UCPEN;
            HWREG8(baseAddress + OFS_UCAxCTL0) &= ~UCPAR;
            break;
        case USCI_A_UART_EVEN_PARITY:
            //Even Parity
            HWREG8(baseAddress + OFS_UCAxCTL0) |= UCPEN;
            HWREG8(baseAddress + OFS_UCAxCTL0) |= UCPAR;
            break;
    }
 
    //Modulation Control Registers
    HWREG16(baseAddress + OFS_UCAxBRW ) = param->clockPrescalar;
    HWREG8(baseAddress + OFS_UCAxMCTL) = ((param->firstModReg<<4) +
                                        (param->secondModReg <<1) +
                                        param->overSampling );
 
    //Asynchronous mode & 8 bit character select & clear mode
    HWREG8(baseAddress + OFS_UCAxCTL0) &=  ~(UCSYNC +
                                             UC7BIT +
                                             UCMODE_3
                                             );
 
    //Configure  UART mode.
    HWREG8(baseAddress + OFS_UCAxCTL0) |= param->uartMode ;
 
    //Reset UCRXIE, UCBRKIE, UCDORM, UCTXADDR, UCTXBRK
    HWREG8(baseAddress + OFS_UCAxCTL1)  &= ~(UCRXEIE + UCBRKIE + UCDORM +
                                             UCTXADDR + UCTXBRK
                                             );
    return (retVal) ;
}
void USCI_A_UART_transmitData ( uint16_t baseAddress,
    uint8_t transmitData
    )
{
    //If interrupts are not used, poll for flags
    if (!(HWREG8(baseAddress + OFS_UCAxIE) & UCTXIE)){
        //Poll for transmit interrupt flag
        while (!(HWREG8(baseAddress + OFS_UCAxIFG) & UCTXIFG));
    }
 
    HWREG8(baseAddress + OFS_UCAxTXBUF) = transmitData;
}
 
uint8_t USCI_A_UART_receiveData (uint16_t baseAddress)
{
    //If interrupts are not used, poll for flags
    if (!(HWREG8(baseAddress + OFS_UCAxIE) & UCRXIE)){
        //Poll for receive interrupt flag
        while (!(HWREG8(baseAddress + OFS_UCAxIFG) & UCRXIFG));
    }
 
    return ( HWREG8(baseAddress + OFS_UCAxRXBUF)) ;
}
 
void USCI_A_UART_enableInterrupt (uint16_t baseAddress,
    uint8_t mask
    )
{
    uint8_t locMask;
 
    locMask = (mask & (USCI_A_UART_RECEIVE_INTERRUPT
        | USCI_A_UART_TRANSMIT_INTERRUPT));
    HWREG8(baseAddress + OFS_UCAxIE) |= locMask;
 
    locMask = (mask & (USCI_A_UART_RECEIVE_ERRONEOUSCHAR_INTERRUPT
        | USCI_A_UART_BREAKCHAR_INTERRUPT));
    HWREG8(baseAddress + OFS_UCAxCTL1) |= locMask;
}
 
void USCI_A_UART_disableInterrupt (uint16_t baseAddress,
    uint8_t mask
    )
{
    uint8_t locMask;
 
    if(locMask = (mask & (USCI_A_UART_RECEIVE_INTERRUPT
        | USCI_A_UART_TRANSMIT_INTERRUPT))) {
        HWREG8(baseAddress + OFS_UCAxIE) &= ~locMask;
    }
 
    if(locMask = (mask & (USCI_A_UART_RECEIVE_ERRONEOUSCHAR_INTERRUPT
        | USCI_A_UART_BREAKCHAR_INTERRUPT))) {
        HWREG8(baseAddress + OFS_UCAxCTL1) &= ~locMask;
    }
}
 
uint8_t USCI_A_UART_getInterruptStatus (uint16_t baseAddress,
    uint8_t mask)
{
    return ( HWREG8(baseAddress + OFS_UCAxIFG) & mask );
}
 
void USCI_A_UART_clearInterrupt (uint16_t baseAddress, uint8_t mask)
{
    //Clear the UART interrupt source.
    HWREG8(baseAddress + OFS_UCAxIFG) &= ~(mask);
}
 
void USCI_A_UART_enable (uint16_t baseAddress)
{
    //Reset the UCSWRST bit to enable the USCI Module
    HWREG8(baseAddress + OFS_UCAxCTL1) &= ~(UCSWRST);
}
 
void USCI_A_UART_disable (uint16_t baseAddress)
{
    //Set the UCSWRST bit to disable the USCI Module
    HWREG8(baseAddress + OFS_UCAxCTL1) |= UCSWRST;
}
 
uint8_t USCI_A_UART_queryStatusFlags (uint16_t baseAddress,
    uint8_t mask)
{
    return ( HWREG8(baseAddress + OFS_UCAxSTAT) & mask );
}
 
void USCI_A_UART_setDormant (uint16_t baseAddress)
{
    HWREG8(baseAddress + OFS_UCAxCTL1) |= UCDORM;
}
 
void USCI_A_UART_resetDormant (uint16_t baseAddress)
{
    HWREG8(baseAddress + OFS_UCAxCTL1) &= ~UCDORM;
}
 
void USCI_A_UART_transmitAddress (uint16_t baseAddress,
    uint8_t transmitAddress)
{
    //Set UCTXADDR bit
    HWREG8(baseAddress + OFS_UCAxCTL1) |= UCTXADDR;
 
    //Place next byte to be sent into the transmit buffer
    HWREG8(baseAddress + OFS_UCAxTXBUF) = transmitAddress;
}
 
void USCI_A_UART_transmitBreak (uint16_t baseAddress)
{
    //Set UCTXADDR bit
    HWREG8(baseAddress + OFS_UCAxCTL1) |= UCTXBRK;
 
    //If current mode is automatic baud-rate detection
    if (USCI_A_UART_AUTOMATIC_BAUDRATE_DETECTION_MODE ==
        (HWREG8(baseAddress + OFS_UCAxCTL0) &
         USCI_A_UART_AUTOMATIC_BAUDRATE_DETECTION_MODE)){
        HWREG8(baseAddress + OFS_UCAxTXBUF) = USCI_A_UART_AUTOMATICBAUDRATE_SYNC;
    } else   {
        HWREG8(baseAddress + OFS_UCAxTXBUF) = DEFAULT_SYNC;
    }
 
    //If interrupts are not used, poll for flags
    if (!(HWREG8(baseAddress + OFS_UCAxIE) & UCTXIE)){
        //Poll for transmit interrupt flag
        while (!(HWREG8(baseAddress + OFS_UCAxIFG) & UCTXIFG));
    }
}
 
uint32_t USCI_A_UART_getReceiveBufferAddressForDMA (uint16_t baseAddress)
{
    return ( baseAddress + OFS_UCAxRXBUF );
}
 
uint32_t USCI_A_UART_getTransmitBufferAddressForDMA (uint16_t baseAddress)
{
    return ( baseAddress + OFS_UCAxTXBUF );
}
 
 
#endif
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//
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