//****************************************************************************** // MSP430xG46x 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 **// // // MSP430xG46x // ----------------- // /|\| XIN|- // | | | // --|RST XOUT|- // | | // | | // | XT2IN|- // | | HF XTAL (455kHz - 8MHz) // | XT2OUT|- // | | // | | // | P1.1/MCLK|-->MCLK = HF XTAL // // K. Quiring/ M. Mitchell // Texas Instruments Inc. // October 2006 // Built with IAR Embedded Workbench Version: 3.41A //****************************************************************************** #include 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 |= 0x002; // P1.1 output direction P1SEL |= 0x002; // P1.1 option select while(1); }