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/* --COPYRIGHT--,BSD_EX
* Copyright (c) 2014, Texas Instruments Incorporated
* 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 following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of Texas Instruments Incorporated nor the names of
* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS 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.
*
*******************************************************************************
*
* MSP430 CODE EXAMPLE DISCLAIMER
*
* MSP430 code examples are self-contained low-level programs that typically
* demonstrate a single peripheral function or device feature in a highly
* concise manner. For this the code may rely on the device's power-on default
* register values and settings such as the clock configuration and care must
* be taken when combining code from several examples to avoid potential side
* effects. Also see www.ti.com/grace for a GUI- and www.ti.com/msp430ware
* for an API functional library-approach to peripheral configuration.
*
* --/COPYRIGHT--*/
//******************************************************************************
// MSP430FR243x Demo - RTC, device enter LPM3.5 and toggle P1.0 in RTC
// interrupt handling every 1s
//
//
// Description: Device enter LPM3.5 after configuring the RTC. The RTC wakes
// the device up from LPM3.5 every second and toggles P1.0.
// It also stores the state of P0OUT in the Backup RAM Registers.
//
// XT1 = 32kHz, ACLK = default, MCLK = SMCLK = default, DCODIV = ~1MHz.
//
// MSP430FR2433
// -----------------
// /|\| |
// | | |
// | | XIN(P2.0)|--
// --|RST | ~32768Hz
// | XOUT(P2.1)|--
// | |
// | P1.0|-->LED
//
// Ling Zhu
// Texas Instruments Inc.
// Jan 2014
// Built with IAR Embedded Workbench v6.20 & Code Composer Studio v6.0.1
//******************************************************************************
#include <msp430.h>
void initGpio(void);
int main(void)
{
WDTCTL = WDTPW | WDTHOLD; // Stop WDT
initGpio(); // Configure GPIO
// Initialize XT1 32kHz crystal
P2SEL0 |= BIT0 | BIT1; // set XT1 pin as second function
do
{
CSCTL7 &= ~(XT1OFFG | DCOFFG); // Clear XT1 and DCO fault flag
SFRIFG1 &= ~OFIFG;
} while (SFRIFG1 & OFIFG); // Test oscillator fault flag
// First determine whether we are coming out of an LPMx.5 or a regular RESET.
if (SYSRSTIV == SYSRSTIV_LPM5WU) // When woken up from LPM3.5, reinit
{
// If MCU wakes up from LPM3.5, re-init and then return to LPM3.5 again.
// Restore P1OUT value from backup RAM memory, keep P1OUT after LPMx.5 reset
P1OUT = *(unsigned int *)BKMEM_BASE;
__enable_interrupt(); // The RTC interrupt should trigger now...
}
else
{
// Device powered up from a cold start.
// It configures the device and puts the device into LPM3.5
// Configure backup memory
*(unsigned int *)BKMEM_BASE = 0;
// Initialize RTC
// Interrupt and reset happen every 1024/32768 * 32 = 1 sec.
RTCMOD = 32-1;
RTCCTL = RTCSS__XT1CLK | RTCSR | RTCPS__1024 | RTCIE;
// Store P1OUT value in backup memory register before enter LPM3.5
*(unsigned int *)BKMEM_BASE = P1OUT;
}
// Enter LPM3.5 mode with interrupts enabled. Note that this operation does
// not return. The LPM3.5 will exit through a RESET event, resulting in a
// re-start of the code.
PMMCTL0_H = PMMPW_H; // Open PMM Registers for write
PMMCTL0_L |= PMMREGOFF; // and set PMMREGOFF
__bis_SR_register(LPM3_bits | GIE);
__no_operation();
return 0;
}
void initGpio(void)
{
P1DIR = 0xFF; P2DIR = 0xFF; P3DIR = 0xFF;
P1REN = 0xFF; P2REN = 0xFF; P3REN = 0xFF;
P1OUT = 0x00; P2OUT = 0x00; P3OUT = 0x00;
// Disable the GPIO power-on default high-impedance mode
// to activate previously configured port settings
PM5CTL0 &= ~LOCKLPM5;
}
#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector = RTC_VECTOR
__interrupt void RTC_ISR(void)
#elif defined(__GNUC__)
void __attribute__ ((interrupt(RTC_VECTOR))) RTC_ISR (void)
#else
#error Compiler not supported!
#endif
{
switch(__even_in_range(RTCIV, RTCIV_RTCIF))
{
case RTCIV_NONE : break; // No interrupt pending
case RTCIV_RTCIF: // RTC Overflow
// Toggle LED on P1.0
P1OUT ^= BIT0;
// Store P1OUT value in backup memory register
*(unsigned int *)BKMEM_BASE = P1OUT;
break;
default: break;
}
}
