Danger-alarm/SOFTWARE-FreeRTOS/Common/drivers/Atmel/at91lib/peripherals/rtt/rtt.c

94 lines
4.1 KiB
C
Raw Permalink Normal View History

2024-06-03 16:27:41 +08:00
/* ----------------------------------------------------------------------------
* 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 "rtt.h"
#include <utility/assert.h>
//------------------------------------------------------------------------------
// Exported functions
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
/// Changes the prescaler value of the given RTT and restarts it. This function
/// disables RTT interrupt sources.
/// \param rtt Pointer to a AT91S_RTTC instance.
/// \param prescaler Prescaler value for the RTT.
//------------------------------------------------------------------------------
void RTT_SetPrescaler(AT91S_RTTC *rtt, unsigned short prescaler)
{
rtt->RTTC_RTMR = (prescaler | AT91C_RTTC_RTTRST);
}
//------------------------------------------------------------------------------
/// Returns the current value of the RTT timer value.
/// \param rtt Pointer to a AT91S_RTTC instance.
//------------------------------------------------------------------------------
unsigned int RTT_GetTime(AT91S_RTTC *rtt)
{
return rtt->RTTC_RTVR;
}
//------------------------------------------------------------------------------
/// Enables the specified RTT interrupt sources.
/// \param rtt Pointer to a AT91S_RTTC instance.
/// \param sources Bitmask of interrupts to enable.
//------------------------------------------------------------------------------
void RTT_EnableIT(AT91S_RTTC *rtt, unsigned int sources)
{
ASSERT((sources & 0x0004FFFF) == 0,
"RTT_EnableIT: Wrong sources value.\n\r");
rtt->RTTC_RTMR |= sources;
}
//------------------------------------------------------------------------------
/// Returns the status register value of the given RTT.
/// \param rtt Pointer to an AT91S_RTTC instance.
//------------------------------------------------------------------------------
unsigned int RTT_GetStatus(AT91S_RTTC *rtt)
{
return rtt->RTTC_RTSR;
}
//------------------------------------------------------------------------------
/// Configures the RTT to generate an alarm at the given time.
/// \param pRtt Pointer to an AT91S_RTTC instance.
/// \param time Alarm time.
//------------------------------------------------------------------------------
void RTT_SetAlarm(AT91S_RTTC *pRtt, unsigned int time)
{
SANITY_CHECK(time > 0);
pRtt->RTTC_RTAR = time - 1;
}