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//******************************************************************************
// MSP430x47xx Demo - Basic Timer, Toggle P5.1 Inside ISR, DCO SMCLK
//
// Description: Toggles P5.1 by xor'ing P5.1 inside of a basic timer ISR.
// SMCLK provides the basic timer clock source. When using default FLL+
// register settings and an external 32kHz watch crystal, LED toggles
// every ~244us.
// ACLK = LFXT1 = 32768Hz, MCLK = SMCLK = default DCO = 32 x ACLK = 1048576Hz
// //* An external watch crystal between XIN & XOUT is required for ACLK *//
//
// MSP430x47xx
// -----------------
// /|\| XIN|-
// | | | 32kHz
// --|RST XOUT|-
// | |
// | P5.1|-->LED
//
//
// P. Thanigai / K.Venkat
// Texas Instruments Inc.
// November 2007
// Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.42A
//*****************************************************************************
#include <msp430x47x4.h>
void main(void)
{
WDTCTL = WDTPW + WDTHOLD; // Stop WDT
FLL_CTL0 |= XCAP18PF; // Set load cap for 32k xtal
P5DIR |= BIT1; // Set P5.1 as output
BTCTL = BTSSEL + BT_fCLK2_DIV256; // SMCLK/256
IE2 |= BTIE; // Enable BT interrupt
_BIS_SR(LPM0_bits + GIE); // Enter LPM0, enable interrupts
}
// Basic Timer Interrupt Service Routine
#pragma vector=BASICTIMER_VECTOR
__interrupt void basic_timer_ISR(void)
{
P5OUT ^= BIT1; // Toggle P5.1
}
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