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//******************************************************************************
// MSP430F23x0 Demo - Timer_B, PWM TB1-2, Up/Down Mode, DCO SMCLK
//
// Description: This program generates two PWM outputs on P4.1,2 using
// Timer_B configured for up/down mode. The value in TBCCR0, 128, defines
// the PWM period/2 and the values in TBCCR1-2 the PWM duty cycles. Using
// ~1.2MHz SMCLK as TBCLK, the timer period is ~213us with a 75% duty
// cycle on P4.1 and 25% on P4.2.
// ACLK = n/a, SMCLK = MCLK = TBCLK = default DCO ~1.2MHz
//
// MSP430F23x0
// -----------------
// /|\| XIN|-
// | | |
// --|RST XOUT|-
// | |
// | P4.1/TB1|--> TBCCR1 - 75% PWM
// | P4.2/TB2|--> TBCCR2 - 25% PWM
//
// A. Dannenberg
// Texas Instruments Inc.
// January 2007
// Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.41A
//******************************************************************************
#include "msp430x23x0.h"
void main(void)
{
WDTCTL = WDTPW + WDTHOLD; // Stop WDT
P4DIR |= 0x06; // P4.1 and P4.2 output
P4SEL |= 0x06; // P4.1 and P4.2 TB1/2 otions
TBCCR0 = 128; // PWM Period/2
TBCCTL1 = OUTMOD_6; // TBCCR1 toggle/set
TBCCR1 = 32; // TBCCR1 PWM Duty Cycle
TBCCTL2 = OUTMOD_6; // TBCCR2 toggle/set
TBCCR2 = 96; // TBCCR2 PWM duty cycle
TBCTL = TBSSEL_2 + MC_3; // SMCLK, updown mode
__bis_SR_register(LPM0_bits); // CPU off
}
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