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 *                       MSP430 CODE EXAMPLE DISCLAIMER

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 * MSP430 code examples are self-contained low-level programs that typically

 * demonstrate a single peripheral function or device feature in a highly

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 * register values and settings such as the clock configuration and care must

 * be taken when combining code from several examples to avoid potential side

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 * for an API functional library-approach to peripheral configuration.

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//******************************************************************************

//  MSP430x24x Demo - Software Toggle P1.0, MCLK = VLO/8

//

//  Description; Pulse P1.0 with a 1/100 active duty cycle using software.

//  Ultra-low frequency ~ 1.5kHz, ultra-low power active mode demonstrated. All 

//  the 6 I/O ports are configured as low outputs to eliminate floating inputs.

//  ACLK = VL0, MCLK = VLO/8 ~ 1.5kHz, SMCLK = n/a

//

//                MSP430F249

//             -----------------

//         /|\|              XIN|-

//          | |                 |

//          --|RST          XOUT|-

//            |                 |

//            |             P1.0|-->LED

//            |        P5.4/MCLK|-->MCLK = VLO/8

//            |        P5.6/ACLK|-->ACLK = VLO

//

//  B. Nisarga

//  Texas Instruments Inc.

//  July 2007

//  Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.42A

//******************************************************************************

#include <msp430.h>



volatile unsigned int i;                    // volatile to prevent optimization



int main(void)

{

  WDTCTL = WDTPW + WDTHOLD;                 // Stop WDT

  BCSCTL3 |= LFXT1S_2;                      // LFXT1 = VLOCLK

  IFG1 &= ~OFIFG;                           // Clear OSCFault flag

  

  __bis_SR_register(SCG1 + SCG0);           // Stop DCO

  BCSCTL2 |= SELM_3 + DIVM_3;               // MCLK = VLO/8

  

  P1DIR = 0xFF;                             // All P1.x outputs

  P1OUT = 0;                                // All P1.x reset

  P2SEL = 0;                                // All P2.x GPIO function

  P2DIR = 0xFF;                             // All P2.x outputs

  P2OUT = 0;                                // All P2.x reset

  P3DIR = 0xFF;                             // All P3.x outputs

  P3OUT = 0;                                // All P3.x reset

  P4DIR = 0xFF;                             // All P4.x outputs

  P4OUT = 0;                                // All P4.x reset

  P5DIR = 0xFF;                             // All P5.x outputs

  P5OUT = 0;                                // All P5.x reset

  P6DIR = 0xFF;                             // All P6.x outputs

  P6OUT = 0;                                // All P6.x reset

  

  P5SEL |= 0x50;                            // P5.4= MCLK option select

                                            // P5.6= ACLK option select

  for (;;)

  {

    P1OUT |= 0x01;                          // P1.0 set

    for (i = 10; i > 0; i--);               // Delay 1x

    P1OUT &= ~0x01;                         // P1.0 reset

    for (i = 1000; i > 0; i--);             // Delay 100x

  }

}