Subversion Repositories openrisc_2011-10-31

/* ----------------------------------------------------------------------------

 *         ATMEL Microcontroller Software Support

 * ----------------------------------------------------------------------------

 * Copyright (c) 2008, Atmel Corporation

 *

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *

 * - Redistributions of source code must retain the above copyright notice,

 * this list of conditions and the disclaimer below.

 *

 * Atmel's name may not be used to endorse or promote products derived from

 * this software without specific prior written permission.

 *

 * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE

 * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,

 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,

 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,

 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 * ----------------------------------------------------------------------------

 */

//------------------------------------------------------------------------------

//      Headers

//------------------------------------------------------------------------------

#include "dbgu.h"

#include <stdarg.h>

#include <board.h>

//------------------------------------------------------------------------------

//      Exported functions

//------------------------------------------------------------------------------

//------------------------------------------------------------------------------

/// Initializes the DBGU with the given parameters, and enables both the

/// transmitter and the receiver.

/// \param mode  Operating mode to configure (see <Modes>).

/// \param baudrate  Desired baudrate.

/// \param mck  Frequency of the system master clock.

//------------------------------------------------------------------------------

void DBGU_Configure(unsigned int mode,

                           unsigned int baudrate,

                           unsigned int mck)

{

    // Reset & disable receiver and transmitter, disable interrupts

    AT91C_BASE_DBGU->DBGU_CR = AT91C_US_RSTRX | AT91C_US_RSTTX;

    AT91C_BASE_DBGU->DBGU_IDR = 0xFFFFFFFF;

    // Configure baud rate

    AT91C_BASE_DBGU->DBGU_BRGR = mck / (baudrate * 16);

    // Configure mode register

    AT91C_BASE_DBGU->DBGU_MR = mode;

    // Disable DMA channel

    AT91C_BASE_DBGU->DBGU_PTCR = AT91C_PDC_RXTDIS | AT91C_PDC_TXTDIS;

    // Enable receiver and transmitter

    AT91C_BASE_DBGU->DBGU_CR = AT91C_US_RXEN | AT91C_US_TXEN;

}

//------------------------------------------------------------------------------

/// Outputs a character on the DBGU line.

/// \param c  Character to send.

//------------------------------------------------------------------------------

static void DBGU_PutChar(unsigned char c)

{

    // Wait for the transmitter to be ready

    while ((AT91C_BASE_DBGU->DBGU_CSR & AT91C_US_TXEMPTY) == 0);

    // Send character

    AT91C_BASE_DBGU->DBGU_THR = c;

    // Wait for the transfer to complete

    while ((AT91C_BASE_DBGU->DBGU_CSR & AT91C_US_TXEMPTY) == 0);

}

//------------------------------------------------------------------------------

/// Reads and returns a character from the DBGU.

//------------------------------------------------------------------------------

unsigned char DBGU_GetChar()

{

    while ((AT91C_BASE_DBGU->DBGU_CSR & AT91C_US_RXRDY) == 0);

    return AT91C_BASE_DBGU->DBGU_RHR;

}

#ifndef NOFPUT

#include <stdio.h>

//------------------------------------------------------------------------------

/// Implementation of fputc using the DBGU as the standard output. Required

/// for printf().

/// Returns the character written if successful, or -1 if the output stream is

/// not stdout or stderr.

/// \param c  Character to write.

/// \param pStream  Output stream.

//------------------------------------------------------------------------------

signed int fputc(signed int c, FILE *pStream)

{

    if ((pStream == stdout) || (pStream == stderr)) {

        DBGU_PutChar(c);

        return c;

    }

    else {

        return EOF;

    }

}

//------------------------------------------------------------------------------

/// Implementation of fputs using the DBGU as the standard output. Required

/// for printf(). Does NOT currently use the PDC.

/// Returns the number of characters written if successful, or -1 if the output

/// stream is not stdout or stderr.

/// \param pStr  String to write.

/// \param pStream  Output stream.

//------------------------------------------------------------------------------

signed int fputs(const char *pStr, FILE *pStream)

{

    signed int num = 0;

    while (*pStr != 0) {

        if (fputc(*pStr, pStream) == -1) {

            return -1;

        }

        num++;

        pStr++;

    }

    return num;

}

#undef putchar

//------------------------------------------------------------------------------

/// Outputs a character on the DBGU. Returns the character itself.

/// \param c  Character to output.

//------------------------------------------------------------------------------

signed int putchar(signed int c)

{

    return fputc(c, stdout);

}

#endif //#ifndef NOFPUT