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rt-thread-official/bsp/lm3s8962/Libraries/driverlib/i2c.c

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Re-normalizing the repo
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//*****************************************************************************
//
// i2c.c - Driver for Inter-IC (I2C) bus block.
//
// Copyright (c) 2005-2011 Texas Instruments Incorporated. All rights reserved.
// Software License Agreement
//
// Texas Instruments (TI) is supplying this software for use solely and
// exclusively on TI's microcontroller products. The software is owned by
// TI and/or its suppliers, and is protected under applicable copyright
// laws. You may not combine this software with "viral" open-source
// software in order to form a larger program.
//
// THIS SOFTWARE IS PROVIDED "AS IS" AND WITH ALL FAULTS.
// 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. TI SHALL NOT, UNDER ANY
// CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR CONSEQUENTIAL
// DAMAGES, FOR ANY REASON WHATSOEVER.
//
// This is part of revision 8264 of the Stellaris Peripheral Driver Library.
//
//*****************************************************************************
//*****************************************************************************
//
//! \addtogroup i2c_api
//! @{
//
//*****************************************************************************
#include "inc/hw_i2c.h"
#include "inc/hw_ints.h"
#include "inc/hw_memmap.h"
#include "inc/hw_sysctl.h"
#include "inc/hw_types.h"
#include "driverlib/debug.h"
#include "driverlib/i2c.h"
#include "driverlib/interrupt.h"
//*****************************************************************************
//
// A mapping of I2C base address to interupt number.
//
//*****************************************************************************
static const unsigned long g_ppulI2CIntMap[][2] =
{
{ I2C0_MASTER_BASE, INT_I2C0 },
{ I2C1_MASTER_BASE, INT_I2C1 },
{ I2C2_MASTER_BASE, INT_I2C2 },
{ I2C3_MASTER_BASE, INT_I2C3 },
{ I2C4_MASTER_BASE, INT_I2C4 },
{ I2C5_MASTER_BASE, INT_I2C5 },
};
//*****************************************************************************
//
//! \internal
//! Checks a I2C master base address.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! This function determines if a I2C master module base address is valid.
//!
//! \return Returns \b true if the base address is valid and \b false
//! otherwise.
//
//*****************************************************************************
#ifdef DEBUG
static tBoolean
I2CMasterBaseValid(unsigned long ulBase)
{
return((ulBase == I2C0_MASTER_BASE) || (ulBase == I2C1_MASTER_BASE) ||
(ulBase == I2C2_MASTER_BASE) || (ulBase == I2C3_MASTER_BASE) ||
(ulBase == I2C4_MASTER_BASE) || (ulBase == I2C5_MASTER_BASE));
}
#endif
//*****************************************************************************
//
//! \internal
//! Checks a I2C slave base address.
//!
//! \param ulBase is the base address of the I2C Slave module.
//!
//! This function determines if a I2C slave module base address is valid.
//!
//! \return Returns \b true if the base address is valid and \b false
//! otherwise.
//
//*****************************************************************************
#ifdef DEBUG
static tBoolean
I2CSlaveBaseValid(unsigned long ulBase)
{
return((ulBase == I2C0_SLAVE_BASE) || (ulBase == I2C1_SLAVE_BASE) ||
(ulBase == I2C2_SLAVE_BASE) || (ulBase == I2C3_SLAVE_BASE) ||
(ulBase == I2C4_SLAVE_BASE) || (ulBase == I2C5_SLAVE_BASE));
}
#endif
//*****************************************************************************
//
//! \internal
//! Gets the I2C interrupt number.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! Given a I2C base address, this function returns the corresponding
//! interrupt number.
//!
//! \return Returns an I2C interrupt number, or -1 if \e ulBase is invalid.
//
//*****************************************************************************
static long
I2CIntNumberGet(unsigned long ulBase)
{
unsigned long ulIdx;
//
// Loop through the table that maps I2C base addresses to interrupt
// numbers.
//
for(ulIdx = 0; ulIdx < (sizeof(g_ppulI2CIntMap) /
sizeof(g_ppulI2CIntMap[0])); ulIdx++)
{
//
// See if this base address matches.
//
if(g_ppulI2CIntMap[ulIdx][0] == ulBase)
{
//
// Return the corresponding interrupt number.
//
return(g_ppulI2CIntMap[ulIdx][1]);
}
}
//
// The base address could not be found, so return an error.
//
return(-1);
}
//*****************************************************************************
//
//! Initializes the I2C Master block.
//!
//! \param ulBase is the base address of the I2C Master module.
//! \param ulI2CClk is the rate of the clock supplied to the I2C module.
//! \param bFast set up for fast data transfers
//!
//! This function initializes operation of the I2C Master block by configuring
//! the bus speed for the master and enabling the I2C Master block.
//!
//! If the parameter \e bFast is \b true, then the master block is set up to
//! transfer data at 400 kbps; otherwise, it is set up to transfer data at
//! 100 kbps.
//!
//! The peripheral clock is the same as the processor clock. This value is
//! returned by SysCtlClockGet(), or it can be explicitly hard coded if it is
//! constant and known (to save the code/execution overhead of a call to
//! SysCtlClockGet()).
//!
//! This function replaces the original I2CMasterInit() API and performs the
//! same actions. A macro is provided in <tt>i2c.h</tt> to map the original
//! API to this API.
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterInitExpClk(unsigned long ulBase, unsigned long ulI2CClk,
tBoolean bFast)
{
unsigned long ulSCLFreq;
unsigned long ulTPR;
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Must enable the device before doing anything else.
//
I2CMasterEnable(ulBase);
//
// Get the desired SCL speed.
//
if(bFast == true)
{
ulSCLFreq = 400000;
}
else
{
ulSCLFreq = 100000;
}
//
// Compute the clock divider that achieves the fastest speed less than or
// equal to the desired speed. The numerator is biased to favor a larger
// clock divider so that the resulting clock is always less than or equal
// to the desired clock, never greater.
//
ulTPR = ((ulI2CClk + (2 * 10 * ulSCLFreq) - 1) / (2 * 10 * ulSCLFreq)) - 1;
HWREG(ulBase + I2C_O_MTPR) = ulTPR;
}
//*****************************************************************************
//
//! Initializes the I2C Slave block.
//!
//! \param ulBase is the base address of the I2C Slave module.
//! \param ucSlaveAddr 7-bit slave address
//!
//! This function initializes operation of the I2C Slave block by configuring
//! the slave address and enabling the I2C Slave block.
//!
//! The parameter \e ucSlaveAddr is the value that is compared against the
//! slave address sent by an I2C master.
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveInit(unsigned long ulBase, unsigned char ucSlaveAddr)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
ASSERT(!(ucSlaveAddr & 0x80));
//
// Must enable the device before doing anything else.
//
I2CSlaveEnable(ulBase);
//
// Set up the slave address.
//
HWREG(ulBase + I2C_O_SOAR) = ucSlaveAddr;
}
//*****************************************************************************
//
//! Sets the I2C slave address.
//!
//! \param ulBase is the base address of the I2C Slave module.
//! \param ucAddrNum determines which slave address is set.
//! \param ucSlaveAddr 7-bit slave address
//!
//! This function writes the specified slave address. The \e ulAddrNum field
//! dictates which slave address is configured. For example, a value of 0
//! configures the primary address and a value of 1, the secondary.
//!
//! \note Not all Stellaris devices support a secondary address. Please consult
//! the device data sheet to know if this feature is supported.
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveAddressSet(unsigned long ulBase, unsigned char ucAddrNum,
unsigned char ucSlaveAddr)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
ASSERT(!(ucAddrNum > 1));
ASSERT(!(ucSlaveAddr & 0x80));
//
// Determine which slave address is being set.
//
switch(ucAddrNum)
{
//
// Set up the primary slave address.
//
case 0:
{
HWREG(ulBase + I2C_O_SOAR) = ucSlaveAddr;
break;
}
//
// Set up and enable the secondary slave address.
//
case 1:
{
HWREG(ulBase + I2C_O_SOAR2) = I2C_SOAR2_OAR2EN | ucSlaveAddr;
break;
}
}
}
//*****************************************************************************
//
//! Enables the I2C Master block.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! This function enables operation of the I2C Master block.
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterEnable(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Enable the master block.
//
HWREG(ulBase + I2C_O_MCR) |= I2C_MCR_MFE;
}
//*****************************************************************************
//
//! Enables the I2C Slave block.
//!
//! \param ulBase is the base address of the I2C Slave module.
//!
//! This fucntion enables operation of the I2C Slave block.
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveEnable(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Enable the clock to the slave block.
//
HWREG(ulBase - I2C0_SLAVE_BASE + I2C0_MASTER_BASE + I2C_O_MCR) |=
I2C_MCR_SFE;
//
// Enable the slave.
//
HWREG(ulBase + I2C_O_SCSR) = I2C_SCSR_DA;
}
//*****************************************************************************
//
//! Disables the I2C master block.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! This function disables operation of the I2C master block.
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterDisable(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Disable the master block.
//
HWREG(ulBase + I2C_O_MCR) &= ~(I2C_MCR_MFE);
}
//*****************************************************************************
//
//! Disables the I2C slave block.
//!
//! \param ulBase is the base address of the I2C Slave module.
//!
//! This function disables operation of the I2C slave block.
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveDisable(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Disable the slave.
//
HWREG(ulBase + I2C_O_SCSR) = 0;
//
// Disable the clock to the slave block.
//
HWREG(ulBase - I2C0_SLAVE_BASE + I2C0_MASTER_BASE + I2C_O_MCR) &=
~(I2C_MCR_SFE);
}
//*****************************************************************************
//
//! Registers an interrupt handler for the I2C module.
//!
//! \param ulBase is the base address of the I2C Master module.
//! \param pfnHandler is a pointer to the function to be called when the
//! I2C interrupt occurs.
//!
//! This function sets the handler to be called when an I2C interrupt occurs.
//! This function enables the global interrupt in the interrupt controller;
//! specific I2C interrupts must be enabled via I2CMasterIntEnable() and
//! I2CSlaveIntEnable(). If necessary, it is the interrupt handler's
//! responsibility to clear the interrupt source via I2CMasterIntClear() and
//! I2CSlaveIntClear().
//!
//! \sa IntRegister() for important information about registering interrupt
//! handlers.
//!
//! \return None.
//
//*****************************************************************************
void
I2CIntRegister(unsigned long ulBase, void (*pfnHandler)(void))
{
unsigned long ulInt;
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Determine the interrupt number based on the I2C port.
//
ulInt = I2CIntNumberGet(ulBase);
//
// Register the interrupt handler, returning an error if an error occurs.
//
IntRegister(ulInt, pfnHandler);
//
// Enable the I2C interrupt.
//
IntEnable(ulInt);
}
//*****************************************************************************
//
//! Unregisters an interrupt handler for the I2C module.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! This function clears the handler to be called when an I2C interrupt
//! occurs. This function also masks off the interrupt in the interrupt r
//! controlle so that the interrupt handler no longer is called.
//!
//! \sa IntRegister() for important information about registering interrupt
//! handlers.
//!
//! \return None.
//
//*****************************************************************************
void
I2CIntUnregister(unsigned long ulBase)
{
unsigned long ulInt;
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Determine the interrupt number based on the I2C port.
//
ulInt = I2CIntNumberGet(ulBase);
//
// Disable the interrupt.
//
IntDisable(ulInt);
//
// Unregister the interrupt handler.
//
IntUnregister(ulInt);
}
//*****************************************************************************
//
//! Enables the I2C Master interrupt.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! This function enables the I2C Master interrupt source.
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterIntEnable(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Enable the master interrupt.
//
HWREG(ulBase + I2C_O_MIMR) = 1;
}
//*****************************************************************************
//
//! Enables individual I2C Master interrupt sources.
//!
//! \param ulBase is the base address of the I2C Master module.
//! \param ulIntFlags is the bit mask of the interrupt sources to be enabled.
//!
//! This function enables the indicated I2C Master interrupt sources. Only the
//! sources that are enabled can be reflected to the processor interrupt;
//! disabled sources have no effect on the processor.
//!
//! The \e ulIntFlags parameter is the logical OR of any of the following:
//!
//! - \b I2C_MASTER_INT_TIMEOUT - Clock Timeout interrupt
//! - \b I2C_MASTER_INT_DATA - Data interrupt
//!
//! \note Not all Stellaris devices support the Clock Timeout interrupt.
//! Please consult the device data sheet to know if this feature is
//! supported.
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterIntEnableEx(unsigned long ulBase, unsigned long ulIntFlags)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Enable the master interrupt.
//
HWREG(ulBase + I2C_O_MIMR) |= ulIntFlags;
}
//*****************************************************************************
//
//! Enables the I2C Slave interrupt.
//!
//! \param ulBase is the base address of the I2C Slave module.
//!
//! This function enables the I2C Slave interrupt source.
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveIntEnable(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Enable the slave interrupt.
//
HWREG(ulBase + I2C_O_SIMR) |= I2C_SLAVE_INT_DATA;
}
//*****************************************************************************
//
//! Enables individual I2C Slave interrupt sources.
//!
//! \param ulBase is the base address of the I2C Slave module.
//! \param ulIntFlags is the bit mask of the interrupt sources to be enabled.
//!
//! This function enables the indicated I2C Slave interrupt sources. Only the
//! sources that are enabled can be reflected to the processor interrupt;
//! disabled sources have no effect on the processor.
//!
//! The \e ulIntFlags parameter is the logical OR of any of the following:
//!
//! - \b I2C_SLAVE_INT_STOP - Stop condition detected interrupt
//! - \b I2C_SLAVE_INT_START - Start condition detected interrupt
//! - \b I2C_SLAVE_INT_DATA - Data interrupt
//!
//! \note Not all Stellaris devices support the Stop and Start condition
//! interrupts. Please consult the device data sheet to know if these features
//! are supported.
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveIntEnableEx(unsigned long ulBase, unsigned long ulIntFlags)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Enable the slave interrupt.
//
HWREG(ulBase + I2C_O_SIMR) |= ulIntFlags;
}
//*****************************************************************************
//
//! Disables the I2C Master interrupt.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! This function disables the I2C Master interrupt source.
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterIntDisable(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Disable the master interrupt.
//
HWREG(ulBase + I2C_O_MIMR) = 0;
}
//*****************************************************************************
//
//! Disables individual I2C Master interrupt sources.
//!
//! \param ulBase is the base address of the I2C Master module.
//! \param ulIntFlags is the bit mask of the interrupt sources to be disabled.
//!
//! This function disables the indicated I2C Master interrupt sources. Only
//! the sources that are enabled can be reflected to the processor interrupt;
//! disabled sources have no effect on the processor.
//!
//! The \e ulIntFlags parameter has the same definition as the \e ulIntFlags
//! parameter to I2CMasterIntEnableEx().
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterIntDisableEx(unsigned long ulBase, unsigned long ulIntFlags)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Disable the master interrupt.
//
HWREG(ulBase + I2C_O_MIMR) &= ~ulIntFlags;
}
//*****************************************************************************
//
//! Disables the I2C Slave interrupt.
//!
//! \param ulBase is the base address of the I2C Slave module.
//!
//! This function disables the I2C Slave interrupt source.
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveIntDisable(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Disable the slave interrupt.
//
HWREG(ulBase + I2C_O_SIMR) &= ~I2C_SLAVE_INT_DATA;
}
//*****************************************************************************
//
//! Disables individual I2C Slave interrupt sources.
//!
//! \param ulBase is the base address of the I2C Slave module.
//! \param ulIntFlags is the bit mask of the interrupt sources to be disabled.
//!
//! This function disables the indicated I2C Slave interrupt sources. Only
//! the sources that are enabled can be reflected to the processor interrupt;
//! disabled sources have no effect on the processor.
//!
//! The \e ulIntFlags parameter has the same definition as the \e ulIntFlags
//! parameter to I2CSlaveIntEnableEx().
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveIntDisableEx(unsigned long ulBase, unsigned long ulIntFlags)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Disable the slave interrupt.
//
HWREG(ulBase + I2C_O_SIMR) &= ~ulIntFlags;
}
//*****************************************************************************
//
//! Gets the current I2C Master interrupt status.
//!
//! \param ulBase is the base address of the I2C Master module.
//! \param bMasked is false if the raw interrupt status is requested and
//! true if the masked interrupt status is requested.
//!
//! This function returns the interrupt status for the I2C Master module.
//! Either the raw interrupt status or the status of interrupts that are allowed to
//! reflect to the processor can be returned.
//!
//! \return The current interrupt status, returned as \b true if active
//! or \b false if not active.
//
//*****************************************************************************
tBoolean
I2CMasterIntStatus(unsigned long ulBase, tBoolean bMasked)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Return either the interrupt status or the raw interrupt status as
// requested.
//
if(bMasked)
{
return((HWREG(ulBase + I2C_O_MMIS)) ? true : false);
}
else
{
return((HWREG(ulBase + I2C_O_MRIS)) ? true : false);
}
}
//*****************************************************************************
//
//! Gets the current I2C Master interrupt status.
//!
//! \param ulBase is the base address of the I2C Master module.
//! \param bMasked is false if the raw interrupt status is requested and
//! true if the masked interrupt status is requested.
//!
//! This function returns the interrupt status for the I2C Master module.
//! Either the raw interrupt status or the status of interrupts that are
//! allowed to reflect to the processor can be returned.
//!
//! \return Returns the current interrupt status, enumerated as a bit field of
//! values described in I2CMasterIntEnableEx().
//
//*****************************************************************************
unsigned long
I2CMasterIntStatusEx(unsigned long ulBase, tBoolean bMasked)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Return either the interrupt status or the raw interrupt status as
// requested.
//
if(bMasked)
{
return(HWREG(ulBase + I2C_O_MMIS));
}
else
{
return(HWREG(ulBase + I2C_O_MRIS));
}
}
//*****************************************************************************
//
//! Gets the current I2C Slave interrupt status.
//!
//! \param ulBase is the base address of the I2C Slave module.
//! \param bMasked is false if the raw interrupt status is requested and
//! true if the masked interrupt status is requested.
//!
//! This function returns the interrupt status for the I2C Slave module.
//! Either the raw interrupt status or the status of interrupts that are
//! allowed to reflect to the processor can be returned.
//!
//! \return The current interrupt status, returned as \b true if active
//! or \b false if not active.
//
//*****************************************************************************
tBoolean
I2CSlaveIntStatus(unsigned long ulBase, tBoolean bMasked)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Return either the interrupt status or the raw interrupt status as
// requested.
//
if(bMasked)
{
return((HWREG(ulBase + I2C_O_SMIS)) ? true : false);
}
else
{
return((HWREG(ulBase + I2C_O_SRIS)) ? true : false);
}
}
//*****************************************************************************
//
//! Gets the current I2C Slave interrupt status.
//!
//! \param ulBase is the base address of the I2C Slave module.
//! \param bMasked is false if the raw interrupt status is requested and
//! true if the masked interrupt status is requested.
//!
//! This function returns the interrupt status for the I2C Slave module.
//! Either the raw interrupt status or the status of interrupts that are
//! allowed to reflect to the processor can be returned.
//!
//! \return Returns the current interrupt status, enumerated as a bit field of
//! values described in I2CSlaveIntEnableEx().
//
//*****************************************************************************
unsigned long
I2CSlaveIntStatusEx(unsigned long ulBase, tBoolean bMasked)
{
unsigned long ulValue;
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Return either the interrupt status or the raw interrupt status as
// requested.
//
if(bMasked)
{
//
// Workaround for I2C slave masked interrupt status register errata
// (7.1) for Dustdevil Rev A0 devices.
//
if(CLASS_IS_DUSTDEVIL && REVISION_IS_A0)
{
ulValue = HWREG(ulBase + I2C_O_SRIS);
return(ulValue & HWREG(ulBase + I2C_O_SIMR));
}
else
{
return(HWREG(ulBase + I2C_O_SMIS));
}
}
else
{
return(HWREG(ulBase + I2C_O_SRIS));
}
}
//*****************************************************************************
//
//! Clears I2C Master interrupt sources.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! The I2C Master interrupt source is cleared, so that it no longer asserts.
//! This function must be called in the interrupt handler to keep the interrupt
//! from being triggered again immediately upon exit.
//!
//! \note Because there is a write buffer in the Cortex-M processor, it may
//! take several clock cycles before the interrupt source is actually cleared.
//! Therefore, it is recommended that the interrupt source be cleared early in
//! the interrupt handler (as opposed to the very last action) to avoid
//! returning from the interrupt handler before the interrupt source is
//! actually cleared. Failure to do so may result in the interrupt handler
//! being immediately reentered (because the interrupt controller still sees
//! the interrupt source asserted).
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterIntClear(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Clear the I2C master interrupt source.
//
HWREG(ulBase + I2C_O_MICR) = I2C_MICR_IC;
//
// Workaround for I2C master interrupt clear errata for rev B Stellaris
// devices. For later devices, this write is ignored and therefore
// harmless (other than the slight performance hit).
//
HWREG(ulBase + I2C_O_MMIS) = I2C_MICR_IC;
}
//*****************************************************************************
//
//! Clears I2C Master interrupt sources.
//!
//! \param ulBase is the base address of the I2C Master module.
//! \param ulIntFlags is a bit mask of the interrupt sources to be cleared.
//!
//! The specified I2C Master interrupt sources are cleared, so that they no
//! longer assert. This function must be called in the interrupt handler to
//! keep the interrupt from being triggered again immediately upon exit.
//!
//! The \e ulIntFlags parameter has the same definition as the \e ulIntFlags
//! parameter to I2CMasterIntEnableEx().
//!
//! \note Because there is a write buffer in the Cortex-M processor, it may
//! take several clock cycles before the interrupt source is actually cleared.
//! Therefore, it is recommended that the interrupt source be cleared early in
//! the interrupt handler (as opposed to the very last action) to avoid
//! returning from the interrupt handler before the interrupt source is
//! actually cleared. Failure to do so may result in the interrupt handler
//! being immediately reentered (because the interrupt controller still sees
//! the interrupt source asserted).
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterIntClearEx(unsigned long ulBase, unsigned long ulIntFlags)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Clear the I2C master interrupt source.
//
HWREG(ulBase + I2C_O_MICR) = ulIntFlags;
}
//*****************************************************************************
//
//! Clears I2C Slave interrupt sources.
//!
//! \param ulBase is the base address of the I2C Slave module.
//!
//! The I2C Slave interrupt source is cleared, so that it no longer asserts.
//! This function must be called in the interrupt handler to keep the interrupt
//! from being triggered again immediately upon exit.
//!
//! \note Because there is a write buffer in the Cortex-M processor, it may
//! take several clock cycles before the interrupt source is actually cleared.
//! Therefore, it is recommended that the interrupt source be cleared early in
//! the interrupt handler (as opposed to the very last action) to avoid
//! returning from the interrupt handler before the interrupt source is
//! actually cleared. Failure to do so may result in the interrupt handler
//! being immediately reentered (because the interrupt controller still sees
//! the interrupt source asserted).
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveIntClear(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Clear the I2C slave interrupt source.
//
HWREG(ulBase + I2C_O_SICR) = I2C_SICR_DATAIC;
}
//*****************************************************************************
//
//! Clears I2C Slave interrupt sources.
//!
//! \param ulBase is the base address of the I2C Slave module.
//! \param ulIntFlags is a bit mask of the interrupt sources to be cleared.
//!
//! The specified I2C Slave interrupt sources are cleared, so that they no
//! longer assert. This function must be called in the interrupt handler to
//! keep the interrupt from being triggered again immediately upon exit.
//!
//! The \e ulIntFlags parameter has the same definition as the \e ulIntFlags
//! parameter to I2CSlaveIntEnableEx().
//!
//! \note Because there is a write buffer in the Cortex-M processor, it may
//! take several clock cycles before the interrupt source is actually cleared.
//! Therefore, it is recommended that the interrupt source be cleared early in
//! the interrupt handler (as opposed to the very last action) to avoid
//! returning from the interrupt handler before the interrupt source is
//! actually cleared. Failure to do so may result in the interrupt handler
//! being immediately reentered (because the interrupt controller still sees
//! the interrupt source asserted).
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveIntClearEx(unsigned long ulBase, unsigned long ulIntFlags)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Clear the I2C slave interrupt source.
//
HWREG(ulBase + I2C_O_SICR) = ulIntFlags;
}
//*****************************************************************************
//
//! Sets the address that the I2C Master places on the bus.
//!
//! \param ulBase is the base address of the I2C Master module.
//! \param ucSlaveAddr 7-bit slave address
//! \param bReceive flag indicating the type of communication with the slave
//!
//! This function configures the address that the I2C Master places on the
//! bus when initiating a transaction. When the \e bReceive parameter is set
//! to \b true, the address indicates that the I2C Master is initiating a
//! read from the slave; otherwise the address indicates that the I2C
//! Master is initiating a write to the slave.
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterSlaveAddrSet(unsigned long ulBase, unsigned char ucSlaveAddr,
tBoolean bReceive)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
ASSERT(!(ucSlaveAddr & 0x80));
//
// Set the address of the slave with which the master will communicate.
//
HWREG(ulBase + I2C_O_MSA) = (ucSlaveAddr << 1) | bReceive;
}
//*****************************************************************************
//
//! Reads the state of the SDA and SCL pins.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! This function returns the state of the I2C bus by providing the real time
//! values of the SDA and SCL pins.
//!
//! \note Not all Stellaris devices support this function. Please consult the
//! device data sheet to know if this feature is supported.
//!
//! \return Returns the state of the bus with SDA in bit position 1 and SCL in
//! bit position 0.
//
//*****************************************************************************
unsigned long
I2CMasterLineStateGet(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Return the line state.
//
return(HWREG(ulBase + I2C_O_MBMON));
}
//*****************************************************************************
//
//! Indicates whether or not the I2C Master is busy.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! This function returns an indication of whether or not the I2C Master is
//! busy transmitting or receiving data.
//!
//! \return Returns \b true if the I2C Master is busy; otherwise, returns
//! \b false.
//
//*****************************************************************************
tBoolean
I2CMasterBusy(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Return the busy status.
//
if(HWREG(ulBase + I2C_O_MCS) & I2C_MCS_BUSY)
{
return(true);
}
else
{
return(false);
}
}
//*****************************************************************************
//
//! Indicates whether or not the I2C bus is busy.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! This function returns an indication of whether or not the I2C bus is busy.
//! This function can be used in a multi-master environment to determine if
//! another master is currently using the bus.
//!
//! \return Returns \b true if the I2C bus is busy; otherwise, returns
//! \b false.
//
//*****************************************************************************
tBoolean
I2CMasterBusBusy(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Return the bus busy status.
//
if(HWREG(ulBase + I2C_O_MCS) & I2C_MCS_BUSBSY)
{
return(true);
}
else
{
return(false);
}
}
//*****************************************************************************
//
//! Controls the state of the I2C Master module.
//!
//! \param ulBase is the base address of the I2C Master module.
//! \param ulCmd command to be issued to the I2C Master module.
//!
//! This function is used to control the state of the Master module send and
//! receive operations. The \e ucCmd parameter can be one of the following
//! values:
//!
//! - \b I2C_MASTER_CMD_SINGLE_SEND
//! - \b I2C_MASTER_CMD_SINGLE_RECEIVE
//! - \b I2C_MASTER_CMD_BURST_SEND_START
//! - \b I2C_MASTER_CMD_BURST_SEND_CONT
//! - \b I2C_MASTER_CMD_BURST_SEND_FINISH
//! - \b I2C_MASTER_CMD_BURST_SEND_ERROR_STOP
//! - \b I2C_MASTER_CMD_BURST_RECEIVE_START
//! - \b I2C_MASTER_CMD_BURST_RECEIVE_CONT
//! - \b I2C_MASTER_CMD_BURST_RECEIVE_FINISH
//! - \b I2C_MASTER_CMD_BURST_RECEIVE_ERROR_STOP
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterControl(unsigned long ulBase, unsigned long ulCmd)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
ASSERT((ulCmd == I2C_MASTER_CMD_SINGLE_SEND) ||
(ulCmd == I2C_MASTER_CMD_SINGLE_RECEIVE) ||
(ulCmd == I2C_MASTER_CMD_BURST_SEND_START) ||
(ulCmd == I2C_MASTER_CMD_BURST_SEND_CONT) ||
(ulCmd == I2C_MASTER_CMD_BURST_SEND_FINISH) ||
(ulCmd == I2C_MASTER_CMD_BURST_SEND_ERROR_STOP) ||
(ulCmd == I2C_MASTER_CMD_BURST_RECEIVE_START) ||
(ulCmd == I2C_MASTER_CMD_BURST_RECEIVE_CONT) ||
(ulCmd == I2C_MASTER_CMD_BURST_RECEIVE_FINISH) ||
(ulCmd == I2C_MASTER_CMD_BURST_RECEIVE_ERROR_STOP));
//
// Send the command.
//
HWREG(ulBase + I2C_O_MCS) = ulCmd;
}
//*****************************************************************************
//
//! Gets the error status of the I2C Master module.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! This function is used to obtain the error status of the Master module send
//! and receive operations.
//!
//! \return Returns the error status, as one of \b I2C_MASTER_ERR_NONE,
//! \b I2C_MASTER_ERR_ADDR_ACK, \b I2C_MASTER_ERR_DATA_ACK, or
//! \b I2C_MASTER_ERR_ARB_LOST.
//
//*****************************************************************************
unsigned long
I2CMasterErr(unsigned long ulBase)
{
unsigned long ulErr;
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Get the raw error state
//
ulErr = HWREG(ulBase + I2C_O_MCS);
//
// If the I2C master is busy, then all the other bit are invalid, and
// don't have an error to report.
//
if(ulErr & I2C_MCS_BUSY)
{
return(I2C_MASTER_ERR_NONE);
}
//
// Check for errors.
//
if(ulErr & (I2C_MCS_ERROR | I2C_MCS_ARBLST))
{
return(ulErr & (I2C_MCS_ARBLST | I2C_MCS_DATACK | I2C_MCS_ADRACK));
}
else
{
return(I2C_MASTER_ERR_NONE);
}
}
//*****************************************************************************
//
//! Transmits a byte from the I2C Master.
//!
//! \param ulBase is the base address of the I2C Master module.
//! \param ucData data to be transmitted from the I2C Master.
//!
//! This function places the supplied data into I2C Master Data Register.
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterDataPut(unsigned long ulBase, unsigned char ucData)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Write the byte.
//
HWREG(ulBase + I2C_O_MDR) = ucData;
}
//*****************************************************************************
//
//! Receives a byte that has been sent to the I2C Master.
//!
//! \param ulBase is the base address of the I2C Master module.
//!
//! This function reads a byte of data from the I2C Master Data Register.
//!
//! \return Returns the byte received from by the I2C Master, cast as an
//! unsigned long.
//
//*****************************************************************************
unsigned long
I2CMasterDataGet(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Read a byte.
//
return(HWREG(ulBase + I2C_O_MDR));
}
//*****************************************************************************
//
//! Sets the Master clock timeout value.
//!
//! \param ulBase is the base address of the I2C Master module.
//! \param ulValue is the number of I2C clocks before the timeout is asserted.
//!
//! This function enables and configures the clock low timeout feature in the
//! I2C peripheral. This feature is implemented as a 12-bit counter, with the
//! upper 8-bits being programmable. For example, to program a timeout of 20ms
//! with a 100kHz SCL frequency, \e ulValue would be 0x7d.
//!
//! \note Not all Stellaris devices support this function. Please consult the
//! device data sheet to know if this feature is supported.
//!
//! \return None.
//
//*****************************************************************************
void
I2CMasterTimeoutSet(unsigned long ulBase, unsigned long ulValue)
{
//
// Check the arguments.
//
ASSERT(I2CMasterBaseValid(ulBase));
//
// Write the timeout value.
//
HWREG(ulBase + I2C_O_MCLKOCNT) = ulValue;
}
//*****************************************************************************
//
//! Configures ACK override behavior of the I2C Slave.
//!
//! \param ulBase is the base address of the I2C Slave module.
//! \param bEnable enables or disables ACK override.
//!
//! This function enables or disables ACK override, allowing the user
//! application to drive the value on SDA during the ACK cycle.
//!
//! \note Not all Stellaris devices support this function. Please consult the
//! device data sheet to know if this feature is supported.
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveACKOverride(unsigned long ulBase, tBoolean bEnable)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Enable or disable based on bEnable.
//
if(bEnable)
{
HWREG(ulBase + I2C_O_SACKCTL) |= I2C_SACKCTL_ACKOEN;
}
else
{
HWREG(ulBase + I2C_O_SACKCTL) &= ~I2C_SACKCTL_ACKOEN;
}
}
//*****************************************************************************
//
//! Writes the ACK value.
//!
//! \param ulBase is the base address of the I2C Slave module.
//! \param bACK chooses whether to ACK (true) or NACK (false) the transfer.
//!
//! This function puts the desired ACK value on SDA during the ACK cycle. The
//! value written is only valid when ACK override is enabled using
//! I2CSlaveACKOverride().
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveACKValueSet(unsigned long ulBase, tBoolean bACK)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// ACK or NACK based on the value of bACK.
//
if(bACK)
{
HWREG(ulBase + I2C_O_SACKCTL) &= ~I2C_SACKCTL_ACKOVAL;
}
else
{
HWREG(ulBase + I2C_O_SACKCTL) |= I2C_SACKCTL_ACKOVAL;
}
}
//*****************************************************************************
//
//! Gets the I2C Slave module status
//!
//! \param ulBase is the base address of the I2C Slave module.
//!
//! This function returns the action requested from a master, if any.
//! Possible values are:
//!
//! - \b I2C_SLAVE_ACT_NONE
//! - \b I2C_SLAVE_ACT_RREQ
//! - \b I2C_SLAVE_ACT_TREQ
//! - \b I2C_SLAVE_ACT_RREQ_FBR
//! - \b I2C_SLAVE_ACT_OWN2SEL
//! - \b I2C_SLAVE_ACT_QCMD
//! - \b I2C_SLAVE_ACT_QCMD_DATA
//!
//! \return Returns \b I2C_SLAVE_ACT_NONE to indicate that no action has been
//! requested of the I2C Slave module, \b I2C_SLAVE_ACT_RREQ to indicate that
//! an I2C master has sent data to the I2C Slave module, \b I2C_SLAVE_ACT_TREQ
//! to indicate that an I2C master has requested that the I2C Slave module send
//! data, \b I2C_SLAVE_ACT_RREQ_FBR to indicate that an I2C master has sent
//! data to the I2C slave and the first byte following the slave's own address
//! has been received, \b I2C_SLAVE_ACT_OWN2SEL to indicate that the second I2C
//! slave address was matched, \b I2C_SLAVE_ACT_QCMD to indicate that a quick
//! command was received, and \b I2C_SLAVE_ACT_QCMD_DATA to indicate that the
//! data bit was set when the quick command was received.
//!
//! \note Not all Stellaris devices support the second I2C slave's own address
//! or the quick command function. Please consult the device data sheet to
//! know if these features are supported.
//
//*****************************************************************************
unsigned long
I2CSlaveStatus(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Return the slave status.
//
return(HWREG(ulBase + I2C_O_SCSR));
}
//*****************************************************************************
//
//! Transmits a byte from the I2C Slave.
//!
//! \param ulBase is the base address of the I2C Slave module.
//! \param ucData data to be transmitted from the I2C Slave
//!
//! This function places the supplied data into I2C Slave Data Register.
//!
//! \return None.
//
//*****************************************************************************
void
I2CSlaveDataPut(unsigned long ulBase, unsigned char ucData)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Write the byte.
//
HWREG(ulBase + I2C_O_SDR) = ucData;
}
//*****************************************************************************
//
//! Receives a byte that has been sent to the I2C Slave.
//!
//! \param ulBase is the base address of the I2C Slave module.
//!
//! This function reads a byte of data from the I2C Slave Data Register.
//!
//! \return Returns the byte received from by the I2C Slave, cast as an
//! unsigned long.
//
//*****************************************************************************
unsigned long
I2CSlaveDataGet(unsigned long ulBase)
{
//
// Check the arguments.
//
ASSERT(I2CSlaveBaseValid(ulBase));
//
// Read a byte.
//
return(HWREG(ulBase + I2C_O_SDR));
}
//*****************************************************************************
//
// Close the Doxygen group.
//! @}
//
//*****************************************************************************