440 lines
15 KiB
C
440 lines
15 KiB
C
//*****************************************************************************
|
|
//
|
|
// comp.c - Driver for the analog comparator.
|
|
//
|
|
// 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 4694 of the Stellaris Peripheral Driver Library.
|
|
//
|
|
//*****************************************************************************
|
|
|
|
//*****************************************************************************
|
|
//
|
|
//! \addtogroup comp_api
|
|
//! @{
|
|
//
|
|
//*****************************************************************************
|
|
|
|
#include "inc/hw_comp.h"
|
|
#include "inc/hw_ints.h"
|
|
#include "inc/hw_memmap.h"
|
|
#include "inc/hw_types.h"
|
|
#include "driverlib/comp.h"
|
|
#include "driverlib/debug.h"
|
|
#include "driverlib/interrupt.h"
|
|
|
|
//*****************************************************************************
|
|
//
|
|
//! Configures a comparator.
|
|
//!
|
|
//! \param ulBase is the base address of the comparator module.
|
|
//! \param ulComp is the index of the comparator to configure.
|
|
//! \param ulConfig is the configuration of the comparator.
|
|
//!
|
|
//! This function will configure a comparator. The \e ulConfig parameter is
|
|
//! the result of a logical OR operation between the \b COMP_TRIG_xxx,
|
|
//! \b COMP_INT_xxx, \b COMP_ASRCP_xxx, and \b COMP_OUTPUT_xxx values.
|
|
//!
|
|
//! The \b COMP_TRIG_xxx term can take on the following values:
|
|
//!
|
|
//! - \b COMP_TRIG_NONE to have no trigger to the ADC.
|
|
//! - \b COMP_TRIG_HIGH to trigger the ADC when the comparator output is high.
|
|
//! - \b COMP_TRIG_LOW to trigger the ADC when the comparator output is low.
|
|
//! - \b COMP_TRIG_FALL to trigger the ADC when the comparator output goes low.
|
|
//! - \b COMP_TRIG_RISE to trigger the ADC when the comparator output goes
|
|
//! high.
|
|
//! - \b COMP_TRIG_BOTH to trigger the ADC when the comparator output goes low
|
|
//! or high.
|
|
//!
|
|
//! The \b COMP_INT_xxx term can take on the following values:
|
|
//!
|
|
//! - \b COMP_INT_HIGH to generate an interrupt when the comparator output is
|
|
//! high.
|
|
//! - \b COMP_INT_LOW to generate an interrupt when the comparator output is
|
|
//! low.
|
|
//! - \b COMP_INT_FALL to generate an interrupt when the comparator output goes
|
|
//! low.
|
|
//! - \b COMP_INT_RISE to generate an interrupt when the comparator output goes
|
|
//! high.
|
|
//! - \b COMP_INT_BOTH to generate an interrupt when the comparator output goes
|
|
//! low or high.
|
|
//!
|
|
//! The \b COMP_ASRCP_xxx term can take on the following values:
|
|
//!
|
|
//! - \b COMP_ASRCP_PIN to use the dedicated Comp+ pin as the reference
|
|
//! voltage.
|
|
//! - \b COMP_ASRCP_PIN0 to use the Comp0+ pin as the reference voltage (this
|
|
//! the same as \b COMP_ASRCP_PIN for the comparator 0).
|
|
//! - \b COMP_ASRCP_REF to use the internally generated voltage as the
|
|
//! reference voltage.
|
|
//!
|
|
//! The \b COMP_OUTPUT_xxx term can take on the following values:
|
|
//!
|
|
//! - \b COMP_OUTPUT_NORMAL to enable a non-inverted output from the comparator
|
|
//! to a device pin.
|
|
//! - \b COMP_OUTPUT_INVERT to enable an inverted output from the comparator to
|
|
//! a device pin.
|
|
//! - \b COMP_OUTPUT_NONE is deprecated and behaves the same as
|
|
//! \b COMP_OUTPUT_NORMAL.
|
|
//!
|
|
//! \return None.
|
|
//
|
|
//*****************************************************************************
|
|
void
|
|
ComparatorConfigure(unsigned long ulBase, unsigned long ulComp,
|
|
unsigned long ulConfig)
|
|
{
|
|
//
|
|
// Check the arguments.
|
|
//
|
|
ASSERT(ulBase == COMP_BASE);
|
|
ASSERT(ulComp < 3);
|
|
|
|
//
|
|
// Configure this comparator.
|
|
//
|
|
HWREG(ulBase + (ulComp * 0x20) + COMP_O_ACCTL0) = ulConfig;
|
|
}
|
|
|
|
//*****************************************************************************
|
|
//
|
|
//! Sets the internal reference voltage.
|
|
//!
|
|
//! \param ulBase is the base address of the comparator module.
|
|
//! \param ulRef is the desired reference voltage.
|
|
//!
|
|
//! This function will set the internal reference voltage value. The voltage
|
|
//! is specified as one of the following values:
|
|
//!
|
|
//! - \b COMP_REF_OFF to turn off the reference voltage
|
|
//! - \b COMP_REF_0V to set the reference voltage to 0 V
|
|
//! - \b COMP_REF_0_1375V to set the reference voltage to 0.1375 V
|
|
//! - \b COMP_REF_0_275V to set the reference voltage to 0.275 V
|
|
//! - \b COMP_REF_0_4125V to set the reference voltage to 0.4125 V
|
|
//! - \b COMP_REF_0_55V to set the reference voltage to 0.55 V
|
|
//! - \b COMP_REF_0_6875V to set the reference voltage to 0.6875 V
|
|
//! - \b COMP_REF_0_825V to set the reference voltage to 0.825 V
|
|
//! - \b COMP_REF_0_928125V to set the reference voltage to 0.928125 V
|
|
//! - \b COMP_REF_0_9625V to set the reference voltage to 0.9625 V
|
|
//! - \b COMP_REF_1_03125V to set the reference voltage to 1.03125 V
|
|
//! - \b COMP_REF_1_134375V to set the reference voltage to 1.134375 V
|
|
//! - \b COMP_REF_1_1V to set the reference voltage to 1.1 V
|
|
//! - \b COMP_REF_1_2375V to set the reference voltage to 1.2375 V
|
|
//! - \b COMP_REF_1_340625V to set the reference voltage to 1.340625 V
|
|
//! - \b COMP_REF_1_375V to set the reference voltage to 1.375 V
|
|
//! - \b COMP_REF_1_44375V to set the reference voltage to 1.44375 V
|
|
//! - \b COMP_REF_1_5125V to set the reference voltage to 1.5125 V
|
|
//! - \b COMP_REF_1_546875V to set the reference voltage to 1.546875 V
|
|
//! - \b COMP_REF_1_65V to set the reference voltage to 1.65 V
|
|
//! - \b COMP_REF_1_753125V to set the reference voltage to 1.753125 V
|
|
//! - \b COMP_REF_1_7875V to set the reference voltage to 1.7875 V
|
|
//! - \b COMP_REF_1_85625V to set the reference voltage to 1.85625 V
|
|
//! - \b COMP_REF_1_925V to set the reference voltage to 1.925 V
|
|
//! - \b COMP_REF_1_959375V to set the reference voltage to 1.959375 V
|
|
//! - \b COMP_REF_2_0625V to set the reference voltage to 2.0625 V
|
|
//! - \b COMP_REF_2_165625V to set the reference voltage to 2.165625 V
|
|
//! - \b COMP_REF_2_26875V to set the reference voltage to 2.26875 V
|
|
//! - \b COMP_REF_2_371875V to set the reference voltage to 2.371875 V
|
|
//!
|
|
//! \return None.
|
|
//
|
|
//*****************************************************************************
|
|
void
|
|
ComparatorRefSet(unsigned long ulBase, unsigned long ulRef)
|
|
{
|
|
//
|
|
// Check the arguments.
|
|
//
|
|
ASSERT(ulBase == COMP_BASE);
|
|
|
|
//
|
|
// Set the voltage reference voltage as requested.
|
|
//
|
|
HWREG(ulBase + COMP_O_ACREFCTL) = ulRef;
|
|
}
|
|
|
|
//*****************************************************************************
|
|
//
|
|
//! Gets the current comparator output value.
|
|
//!
|
|
//! \param ulBase is the base address of the comparator module.
|
|
//! \param ulComp is the index of the comparator.
|
|
//!
|
|
//! This function retrieves the current value of the comparator output.
|
|
//!
|
|
//! \return Returns \b true if the comparator output is high and \b false if
|
|
//! the comparator output is low.
|
|
//
|
|
//*****************************************************************************
|
|
tBoolean
|
|
ComparatorValueGet(unsigned long ulBase, unsigned long ulComp)
|
|
{
|
|
//
|
|
// Check the arguments.
|
|
//
|
|
ASSERT(ulBase == COMP_BASE);
|
|
ASSERT(ulComp < 3);
|
|
|
|
//
|
|
// Return the appropriate value based on the comparator's present output
|
|
// value.
|
|
//
|
|
if(HWREG(ulBase + (ulComp * 0x20) + COMP_O_ACSTAT0) & COMP_ACSTAT0_OVAL)
|
|
{
|
|
return(true);
|
|
}
|
|
else
|
|
{
|
|
return(false);
|
|
}
|
|
}
|
|
|
|
//*****************************************************************************
|
|
//
|
|
//! Registers an interrupt handler for the comparator interrupt.
|
|
//!
|
|
//! \param ulBase is the base address of the comparator module.
|
|
//! \param ulComp is the index of the comparator.
|
|
//! \param pfnHandler is a pointer to the function to be called when the
|
|
//! comparator interrupt occurs.
|
|
//!
|
|
//! This sets the handler to be called when the comparator interrupt occurs.
|
|
//! This will enable the interrupt in the interrupt controller; it is the
|
|
//! interrupt-handler's responsibility to clear the interrupt source via
|
|
//! ComparatorIntClear().
|
|
//!
|
|
//! \sa IntRegister() for important information about registering interrupt
|
|
//! handlers.
|
|
//!
|
|
//! \return None.
|
|
//
|
|
//*****************************************************************************
|
|
void
|
|
ComparatorIntRegister(unsigned long ulBase, unsigned long ulComp,
|
|
void (*pfnHandler)(void))
|
|
{
|
|
//
|
|
// Check the arguments.
|
|
//
|
|
ASSERT(ulBase == COMP_BASE);
|
|
ASSERT(ulComp < 3);
|
|
|
|
//
|
|
// Register the interrupt handler, returning an error if an error occurs.
|
|
//
|
|
IntRegister(INT_COMP0 + ulComp, pfnHandler);
|
|
|
|
//
|
|
// Enable the interrupt in the interrupt controller.
|
|
//
|
|
IntEnable(INT_COMP0 + ulComp);
|
|
|
|
//
|
|
// Enable the comparator interrupt.
|
|
//
|
|
HWREG(ulBase + COMP_O_ACINTEN) |= 1 << ulComp;
|
|
}
|
|
|
|
//*****************************************************************************
|
|
//
|
|
//! Unregisters an interrupt handler for a comparator interrupt.
|
|
//!
|
|
//! \param ulBase is the base address of the comparator module.
|
|
//! \param ulComp is the index of the comparator.
|
|
//!
|
|
//! This function will clear the handler to be called when a comparator
|
|
//! interrupt occurs. This will also mask off the interrupt in the interrupt
|
|
//! controller so that the interrupt handler no longer is called.
|
|
//!
|
|
//! \sa IntRegister() for important information about registering interrupt
|
|
//! handlers.
|
|
//!
|
|
//! \return None.
|
|
//
|
|
//*****************************************************************************
|
|
void
|
|
ComparatorIntUnregister(unsigned long ulBase, unsigned long ulComp)
|
|
{
|
|
//
|
|
// Check the arguments.
|
|
//
|
|
ASSERT(ulBase == COMP_BASE);
|
|
ASSERT(ulComp < 3);
|
|
|
|
//
|
|
// Disable the comparator interrupt.
|
|
//
|
|
HWREG(ulBase + COMP_O_ACINTEN) &= ~(1 << ulComp);
|
|
|
|
//
|
|
// Disable the interrupt in the interrupt controller.
|
|
//
|
|
IntDisable(INT_COMP0 + ulComp);
|
|
|
|
//
|
|
// Unregister the interrupt handler.
|
|
//
|
|
IntUnregister(INT_COMP0 + ulComp);
|
|
}
|
|
|
|
//*****************************************************************************
|
|
//
|
|
//! Enables the comparator interrupt.
|
|
//!
|
|
//! \param ulBase is the base address of the comparator module.
|
|
//! \param ulComp is the index of the comparator.
|
|
//!
|
|
//! This function enables generation of an interrupt from the specified
|
|
//! comparator. Only comparators whose interrupts are enabled can be reflected
|
|
//! to the processor.
|
|
//!
|
|
//! \return None.
|
|
//
|
|
//*****************************************************************************
|
|
void
|
|
ComparatorIntEnable(unsigned long ulBase, unsigned long ulComp)
|
|
{
|
|
//
|
|
// Check the arguments.
|
|
//
|
|
ASSERT(ulBase == COMP_BASE);
|
|
ASSERT(ulComp < 3);
|
|
|
|
//
|
|
// Enable the comparator interrupt.
|
|
//
|
|
HWREG(ulBase + COMP_O_ACINTEN) |= 1 << ulComp;
|
|
}
|
|
|
|
//*****************************************************************************
|
|
//
|
|
//! Disables the comparator interrupt.
|
|
//!
|
|
//! \param ulBase is the base address of the comparator module.
|
|
//! \param ulComp is the index of the comparator.
|
|
//!
|
|
//! This function disables generation of an interrupt from the specified
|
|
//! comparator. Only comparators whose interrupts are enabled can be reflected
|
|
//! to the processor.
|
|
//!
|
|
//! \return None.
|
|
//
|
|
//*****************************************************************************
|
|
void
|
|
ComparatorIntDisable(unsigned long ulBase, unsigned long ulComp)
|
|
{
|
|
//
|
|
// Check the arguments.
|
|
//
|
|
ASSERT(ulBase == COMP_BASE);
|
|
ASSERT(ulComp < 3);
|
|
|
|
//
|
|
// Disable the comparator interrupt.
|
|
//
|
|
HWREG(ulBase + COMP_O_ACINTEN) &= ~(1 << ulComp);
|
|
}
|
|
|
|
//*****************************************************************************
|
|
//
|
|
//! Gets the current interrupt status.
|
|
//!
|
|
//! \param ulBase is the base address of the comparator module.
|
|
//! \param ulComp is the index of the comparator.
|
|
//! \param bMasked is \b false if the raw interrupt status is required and
|
|
//! \b true if the masked interrupt status is required.
|
|
//!
|
|
//! This returns the interrupt status for the comparator. Either the raw or
|
|
//! the masked interrupt status can be returned.
|
|
//!
|
|
//! \return \b true if the interrupt is asserted and \b false if it is not
|
|
//! asserted.
|
|
//
|
|
//*****************************************************************************
|
|
tBoolean
|
|
ComparatorIntStatus(unsigned long ulBase, unsigned long ulComp,
|
|
tBoolean bMasked)
|
|
{
|
|
//
|
|
// Check the arguments.
|
|
//
|
|
ASSERT(ulBase == COMP_BASE);
|
|
ASSERT(ulComp < 3);
|
|
|
|
//
|
|
// Return either the interrupt status or the raw interrupt status as
|
|
// requested.
|
|
//
|
|
if(bMasked)
|
|
{
|
|
return(((HWREG(ulBase + COMP_O_ACMIS) >> ulComp) & 1) ? true : false);
|
|
}
|
|
else
|
|
{
|
|
return(((HWREG(ulBase + COMP_O_ACRIS) >> ulComp) & 1) ? true : false);
|
|
}
|
|
}
|
|
|
|
//*****************************************************************************
|
|
//
|
|
//! Clears a comparator interrupt.
|
|
//!
|
|
//! \param ulBase is the base address of the comparator module.
|
|
//! \param ulComp is the index of the comparator.
|
|
//!
|
|
//! The comparator interrupt is cleared, so that it no longer asserts. This
|
|
//! must be done in the interrupt handler to keep it from being called again
|
|
//! immediately upon exit. Note that for a level triggered interrupt, the
|
|
//! interrupt cannot be cleared until it stops asserting.
|
|
//!
|
|
//! \note Since there is a write buffer in the Cortex-M3 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 (since NVIC still sees the interrupt source
|
|
//! asserted).
|
|
//!
|
|
//! \return None.
|
|
//
|
|
//*****************************************************************************
|
|
void
|
|
ComparatorIntClear(unsigned long ulBase, unsigned long ulComp)
|
|
{
|
|
//
|
|
// Check the arguments.
|
|
//
|
|
ASSERT(ulBase == COMP_BASE);
|
|
ASSERT(ulComp < 3);
|
|
|
|
//
|
|
// Clear the interrupt.
|
|
//
|
|
HWREG(ulBase + COMP_O_ACMIS) = 1 << ulComp;
|
|
}
|
|
|
|
//*****************************************************************************
|
|
//
|
|
// Close the Doxygen group.
|
|
//! @}
|
|
//
|
|
//*****************************************************************************
|