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//******************************************************************************
// MSP430x47xx Demo - FLL+, MCLK Configured to Operate from XT2 HF XTAL
//
// Description: Proper selection of an external HF XTAL for MCLK is
// demonstrated using HF XT2 OSC. OFIFG is polled until the HF XTAL
// is stable - only then is MCLK sourced by XT2. MCLK is buffered on P1.1.
// //** HF XTAL NOT INSTALLED ON FET **//
//
// MSP430x47xx
// -----------------
// /|\| XIN|-
// | | |
// --|RST XOUT|-
// | |
// | |
// | XT2IN|-
// | | HF XTAL (455kHz - 16MHz)
// | XT2OUT|-
// | |
// | |
// | P1.1/MCLK|-->MCLK = HF XTAL
//
// 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)
{
volatile unsigned int i;
WDTCTL = WDTPW+WDTHOLD; // Stop WDT
_BIS_SR(OSCOFF + SCG0 + GIE); // Disable LFXT1 xtal osc & FLL loop
FLL_CTL1 &= ~XT2OFF; // Activate XT2 high freq xtal
// Wait for xtal to stabilize
do
{
IFG1 &= ~OFIFG; // Clear OSCFault flag
for (i = 5; i > 0; i--); // Time for flag to set
}
while ((IFG1 & OFIFG)); // OSCFault flag still set?
FLL_CTL1 |= SELM1; // MCLK = XT2
P1DIR |= BIT1; // P1.1 output direction
P1SEL |= BIT1; // P1.1 option select
while(1);
}
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