?? fet140_hfxtal.c
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//******************************************************************************
// MSP-FET430P140 Demo - LFXT1 / MCLK configured to operate with HF XTAL
//
// Description; Proper selection of an external HF XTAL for MCLK is shown by
// first polling the OSC fault until XTAL is stable - only then is MCLK
// sourced by LFXT1. MCLK is on P5.4
// ** HF XTAL NOT INSTALLED ON FET **//
//
// MSP430F149
// -----------------
// /|\| XIN|-
// | | | HF XTAL (455k - 8Mhz)
// --|RST XOUT|-
// | |
// | P5.4|-->MCLK = XTAL
//
//
// M. Buccini
// Texas Instruments, Inc
// January 2002
//******************************************************************************
#include <msp430x14x.h>
void main(void)
{
unsigned int i;
WDTCTL = WDTPW + WDTHOLD; // Stop WDT
BCSCTL1 |= XTS; // ACLK = LFXT1 = HF XTAL
P5SEL |= 0x10; // P5.4 = MCLK
P5DIR |= 0x10; // P5.4 output direction
do
{
IFG1 &= ~OFIFG; // Clear OSCFault flag
for (i = 0xFF; i > 0; i--); // Time for flag to set
}
while ((IFG1 & OFIFG) == OFIFG); // OSCFault flag still set?
BCSCTL2 |= SELM1+SELM0; // MCLK = LFXT1 (safe)
for (;;); // Do nothing
}
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