bl_i2c.c

基于周立功公司的EasyARM615开发套件的串口驱动程序

//*****************************************************************************
//
// bl_i2c.c - This file contains the function used to transfer data via the I2C
//            port.
//
// Copyright (c) 2006-2007 Luminary Micro, Inc.  All rights reserved.
// 
// Software License Agreement
// 
// Luminary Micro, Inc. (LMI) is supplying this software for use solely and
// exclusively on LMI's microcontroller products.
// 
// The software is owned by LMI and/or its suppliers, and is protected under
// applicable copyright laws.  All rights are reserved.  You may not combine
// this software with "viral" open-source software in order to form a larger
// program.  Any use in violation of the foregoing restrictions may subject
// the user to criminal sanctions under applicable laws, as well as to civil
// liability for the breach of the terms and conditions of this license.
// 
// THIS SOFTWARE IS PROVIDED "AS IS".  NO WARRANTIES, WHETHER EXPRESS, IMPLIED
// OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE.
// LMI SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR
// CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
// 
// This is part of revision 1928 of the Stellaris Peripheral Driver Library.
//
//*****************************************************************************

#include "../hw_gpio.h"
#include "../hw_i2c.h"
#include "../hw_memmap.h"
#include "../hw_sysctl.h"
#include "../hw_types.h"
#include "bl_config.h"
#include "bl_i2c.h"

//*****************************************************************************
//
//! \addtogroup boot_loader_api
//! @{
//
//*****************************************************************************
#if defined(I2C_ENABLE_UPDATE) || defined(DOXYGEN)

//*****************************************************************************
//
//! Sends data over the I2C port.
//!
//! \param pucData is the buffer containing the data to write out to the I2C
//! port.
//! \param ulSize is the number of bytes provided in \e pucData buffer that
//! will be written out to the I2C port.
//!
//! This function sends \e ulSize bytes of data from the buffer pointed to by
//! \e pucData via the I2C port.  The function will wait till the I2C Slave
//! port has been properly addressed by the I2C Master device before sending
//! the first byte.
//!
//! This function is contained in <tt>bl_i2c.c</tt>.
//!
//! \return None.
//
//*****************************************************************************
void
I2CSend(const unsigned char *pucData, unsigned long ulSize)
{
    //
    // Transmit the number of bytes requested on the UART port.
    //
    while(ulSize--)
    {
        //
        // Wait for request to come in at slave.
        //
        while(!(HWREG(I2C0_SLAVE_BASE + I2C_O_SCSR) & I2C_SCSR_TREQ))
        {
        }

        //
        // Send out the next byte.
        //
        HWREG(I2C0_SLAVE_BASE + I2C_O_SDR) = *pucData++;
    }
}

//*****************************************************************************
//
//! Waits until all data has been transmitted by the I2C port.
//!
//! This function waits until all data written to the I2C port has been read by
//! the master.
//!
//! This function is contained in <tt>bl_i2c.c</tt>.
//!
//! \return None.
//
//*****************************************************************************
void
I2CFlush(void)
{
    //
    // Wait until the I2C bus is no longer busy, meaning that the last byte has
    // been sent.
    //
    while(HWREG(I2C0_MASTER_BASE + I2C_O_MCS) & I2C_MCS_BUSBSY)
    {
    }
}

//*****************************************************************************
//
//! Receives data over the I2C port.
//!
//! \param pucData is the buffer to read data into from the I2C port.
//! \param ulSize is the number of bytes provided in the \e pucData buffer that
//! should be written with data from the I2C port.
//!
//! This function reads back \e ulSize bytes of data from the I2C port, into
//! the buffer that is pointed to by \e pucData.  This function will not return
//! until \e ulSize number of bytes have been received.  This function will
//! wait till the I2C Slave port has been properly addressed by the I2C Master
//! before reading the first byte of data from the I2C port.
//!
//! This function is contained in <tt>bl_i2c.c</tt>.
//!
//! \return None.
//
//*****************************************************************************
void
I2CReceive(unsigned char *pucData, unsigned long ulSize)
{
    //
    // Send out the number of bytes requested.
    //
    while(ulSize--)
    {
        //
        // Wait until the slave has received the character.
        //
        while(!(HWREG(I2C0_SLAVE_BASE + I2C_O_SCSR) & I2C_SCSR_RREQ))
        {
        }

        //
        // Receive a byte from the I2C.
        //
        *pucData++ = HWREG(I2C0_SLAVE_BASE + I2C_O_SDR);
    }
}

//*****************************************************************************
//
// Close the Doxygen group.
//! @}
//
//*****************************************************************************
#endif