timer.c

基于TI公司Cortex-M3的uart超级通信开发

//*****************************************************************************
//
// timer.c - Driver for the timer module.
//
// Copyright (c) 2005-2009 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 5228 of the Stellaris Peripheral Driver Library.
//
//*****************************************************************************

//*****************************************************************************
//
//! \addtogroup timer_api
//! @{
//
//*****************************************************************************

#include "inc/hw_ints.h"
#include "inc/hw_memmap.h"
#include "inc/hw_timer.h"
#include "inc/hw_types.h"
#include "driverlib/debug.h"
#include "driverlib/interrupt.h"
#include "driverlib/timer.h"

//*****************************************************************************
//
//! \internal
//! Checks a timer base address.
//!
//! \param ulBase is the base address of the timer module.
//!
//! This function determines if a timer module base address is valid.
//!
//! \return Returns \b true if the base address is valid and \b false
//! otherwise.
//
//*****************************************************************************
#ifdef DEBUG
static tBoolean
TimerBaseValid(unsigned long ulBase)
{
    return((ulBase == TIMER0_BASE) || (ulBase == TIMER1_BASE) ||
           (ulBase == TIMER2_BASE) || (ulBase == TIMER3_BASE));
}
#endif

//*****************************************************************************
//
//! Enables the timer(s).
//!
//! \param ulBase is the base address of the timer module.
//! \param ulTimer specifies the timer(s) to enable; must be one of \b TIMER_A,
//! \b TIMER_B, or \b TIMER_BOTH.
//!
//! This will enable operation of the timer module.  The timer must be
//! configured before it is enabled.
//!
//! \return None.
//
//*****************************************************************************
void
TimerEnable(unsigned long ulBase, unsigned long ulTimer)
{
    //
    // Check the arguments.
    //
    ASSERT(TimerBaseValid(ulBase));
    ASSERT((ulTimer == TIMER_A) || (ulTimer == TIMER_B) ||
           (ulTimer == TIMER_BOTH));

    //
    // Enable the timer(s) module.
    //
    HWREG(ulBase + TIMER_O_CTL) |= ulTimer & (TIMER_CTL_TAEN | TIMER_CTL_TBEN);
}

//*****************************************************************************
//
//! Disables the timer(s).
//!
//! \param ulBase is the base address of the timer module.
//! \param ulTimer specifies the timer(s) to disable; must be one of
//! \b TIMER_A, \b TIMER_B, or \b TIMER_BOTH.
//!
//! This will disable operation of the timer module.
//!
//! \return None.
//
//*****************************************************************************
void
TimerDisable(unsigned long ulBase, unsigned long ulTimer)
{
    //
    // Check the arguments.
    //
    ASSERT(TimerBaseValid(ulBase));
    ASSERT((ulTimer == TIMER_A) || (ulTimer == TIMER_B) ||
           (ulTimer == TIMER_BOTH));

    //
    // Disable the timer module.
    //
    HWREG(ulBase + TIMER_O_CTL) &= ~(ulTimer &
                                     (TIMER_CTL_TAEN | TIMER_CTL_TBEN));
}

//*****************************************************************************
//
//! Configures the timer(s).
//!
//! \param ulBase is the base address of the timer module.
//! \param ulConfig is the configuration for the timer.
//!
//! This function configures the operating mode of the timer(s).  The timer
//! module is disabled before being configured, and is left in the disabled
//! state.  The configuration is specified in \e ulConfig as one of the
//! following values:
//!
//! - \b TIMER_CFG_32_BIT_OS - 32-bit one shot timer
//! - \b TIMER_CFG_32_BIT_PER - 32-bit periodic timer
//! - \b TIMER_CFG_32_RTC - 32-bit real time clock timer
//! - \b TIMER_CFG_16_BIT_PAIR - Two 16-bit timers
//!
//! When configured for a pair of 16-bit timers, each timer is separately
//! configured.  The first timer is configured by setting \e ulConfig to
//! the result of a logical OR operation between one of the following values
//! and \e ulConfig:
//!
//! - \b TIMER_CFG_A_ONE_SHOT - 16-bit one shot timer
//! - \b TIMER_CFG_A_PERIODIC - 16-bit periodic timer
//! - \b TIMER_CFG_A_CAP_COUNT - 16-bit edge count capture
//! - \b TIMER_CFG_A_CAP_TIME - 16-bit edge time capture
//! - \b TIMER_CFG_A_PWM - 16-bit PWM output
//!
//! Similarly, the second timer is configured by setting \e ulConfig to
//! the result of a logical OR operation between one of the corresponding
//! \b TIMER_CFG_B_* values and \e ulConfig.
//!
//! \return None.
//
//*****************************************************************************
void
TimerConfigure(unsigned long ulBase, unsigned long ulConfig)
{
    //
    // Check the arguments.
    //
    ASSERT(TimerBaseValid(ulBase));
    ASSERT((ulConfig == TIMER_CFG_32_BIT_OS) ||
           (ulConfig == TIMER_CFG_32_BIT_PER) ||
           (ulConfig == TIMER_CFG_32_RTC) ||
           ((ulConfig & 0xff000000) == TIMER_CFG_16_BIT_PAIR));
    ASSERT(((ulConfig & 0xff000000) != TIMER_CFG_16_BIT_PAIR) ||
           ((((ulConfig & 0x000000ff) == TIMER_CFG_A_ONE_SHOT) ||
             ((ulConfig & 0x000000ff) == TIMER_CFG_A_PERIODIC) ||
             ((ulConfig & 0x000000ff) == TIMER_CFG_A_CAP_COUNT) ||
             ((ulConfig & 0x000000ff) == TIMER_CFG_A_CAP_TIME) ||
             ((ulConfig & 0x000000ff) == TIMER_CFG_A_PWM)) &&
            (((ulConfig & 0x0000ff00) == TIMER_CFG_B_ONE_SHOT) ||
             ((ulConfig & 0x0000ff00) == TIMER_CFG_B_PERIODIC) ||
             ((ulConfig & 0x0000ff00) == TIMER_CFG_B_CAP_COUNT) ||
             ((ulConfig & 0x0000ff00) == TIMER_CFG_B_CAP_TIME) ||
             ((ulConfig & 0x0000ff00) == TIMER_CFG_B_PWM))));

    //
    // Disable the timers.
    //
    HWREG(ulBase + TIMER_O_CTL) &= ~(TIMER_CTL_TAEN | TIMER_CTL_TBEN);

    //
    // Set the global timer configuration.
    //
    HWREG(ulBase + TIMER_O_CFG) = ulConfig >> 24;

    //
    // Set the configuration of the A and B timers.  Note that the B timer
    // configuration is ignored by the hardware in 32-bit modes.
    //
    HWREG(ulBase + TIMER_O_TAMR) = ulConfig & 255;
    HWREG(ulBase + TIMER_O_TBMR) = (ulConfig >> 8) & 255;
}

//*****************************************************************************
//
//! Controls the output level.
//!
//! \param ulBase is the base address of the timer module.
//! \param ulTimer specifies the timer(s) to adjust; must be one of \b TIMER_A,
//! \b TIMER_B, or \b TIMER_BOTH.
//! \param bInvert specifies the output level.
//!
//! This function sets the PWM output level for the specified timer.  If the
//! \e bInvert parameter is \b true, then the timer's output will be made
//! active low; otherwise, it will be made active high.
//!
//! \return None.
//
//*****************************************************************************
void
TimerControlLevel(unsigned long ulBase, unsigned long ulTimer,
                  tBoolean bInvert)
{
    //
    // Check the arguments.
    //
    ASSERT(TimerBaseValid(ulBase));
    ASSERT((ulTimer == TIMER_A) || (ulTimer == TIMER_B) ||
           (ulTimer == TIMER_BOTH));

    //
    // Set the output levels as requested.
    //
    ulTimer &= TIMER_CTL_TAPWML | TIMER_CTL_TBPWML;
    HWREG(ulBase + TIMER_O_CTL) = (bInvert ?
                                   (HWREG(ulBase + TIMER_O_CTL) | ulTimer) :
                                   (HWREG(ulBase + TIMER_O_CTL) & ~(ulTimer)));
}

//*****************************************************************************
//
//! Enables or disables the trigger output.
//!
//! \param ulBase is the base address of the timer module.
//! \param ulTimer specifies the timer to adjust; must be one of \b TIMER_A,
//! \b TIMER_B, or \b TIMER_BOTH.
//! \param bEnable specifies the desired trigger state.
//!
//! This function controls the trigger output for the specified timer.  If the
//! \e bEnable parameter is \b true, then the timer's output trigger is
//! enabled; otherwise it is disabled.
//!
//! \return None.
//
//*****************************************************************************
void
TimerControlTrigger(unsigned long ulBase, unsigned long ulTimer,
                    tBoolean bEnable)
{
    //
    // Check the arguments.
    //
    ASSERT(TimerBaseValid(ulBase));
    ASSERT((ulTimer == TIMER_A) || (ulTimer == TIMER_B) ||
           (ulTimer == TIMER_BOTH));

    //
    // Set the trigger output as requested.
    //
    ulTimer &= TIMER_CTL_TAOTE | TIMER_CTL_TBOTE;
    HWREG(ulBase + TIMER_O_CTL) = (bEnable ?
                                   (HWREG(ulBase + TIMER_O_CTL) | ulTimer) :
                                   (HWREG(ulBase + TIMER_O_CTL) & ~(ulTimer)));
}

//*****************************************************************************
//
//! Controls the event type.
//!
//! \param ulBase is the base address of the timer module.
//! \param ulTimer specifies the timer(s) to be adjusted; must be one of
//! \b TIMER_A, \b TIMER_B, or \b TIMER_BOTH.
//! \param ulEvent specifies the type of event; must be one of
//! \b TIMER_EVENT_POS_EDGE, \b TIMER_EVENT_NEG_EDGE, or
//! \b TIMER_EVENT_BOTH_EDGES.
//!
//! This function sets the signal edge(s) that will trigger the timer when in
//! capture mode.
//!
//! \return None.
//
//*****************************************************************************
void
TimerControlEvent(unsigned long ulBase, unsigned long ulTimer,
                  unsigned long ulEvent)
{
    //
    // Check the arguments.
    //
    ASSERT(TimerBaseValid(ulBase));
    ASSERT((ulTimer == TIMER_A) || (ulTimer == TIMER_B) ||
           (ulTimer == TIMER_BOTH));

    //
    // Set the event type.
    //
    ulEvent &= ulTimer & (TIMER_CTL_TAEVENT_M | TIMER_CTL_TBEVENT_M);
    HWREG(ulBase + TIMER_O_CTL) = ((HWREG(ulBase + TIMER_O_CTL) &
                                    ~(TIMER_CTL_TAEVENT_M |
                                      TIMER_CTL_TBEVENT_M)) | ulEvent);
}

//*****************************************************************************
//
//! Controls the stall handling.
//!
//! \param ulBase is the base address of the timer module.
//! \param ulTimer specifies the timer(s) to be adjusted; must be one of
//! \b TIMER_A, \b TIMER_B, or \b TIMER_BOTH.
//! \param bStall specifies the response to a stall signal.
//!
//! This function controls the stall response for the specified timer.  If the
//! \e bStall parameter is \b true, then the timer will stop counting if the
//! processor enters debug mode; otherwise the timer will keep running while in
//! debug mode.
//!
//! \return None.
//
//*****************************************************************************
void
TimerControlStall(unsigned long ulBase, unsigned long ulTimer,
                  tBoolean  bStall)
{
    //
    // Check the arguments.
    //
    ASSERT(TimerBaseValid(ulBase));
    ASSERT((ulTimer == TIMER_A) || (ulTimer == TIMER_B) ||
           (ulTimer == TIMER_BOTH));