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问 使用MSP430F133的Timer_A能否输出3路PWM信号？ 答 1: 请教您的实现方法？ 答 2: #include <MSP430x14x.h>

void main(void)
{
unsigned int i;
WDTCTL = WDTPW + WDTHOLD; // Stop WDT
BCSCTL1 |= XTS; // ACLK= LFXT1 = HF XTAL

do
{
IFG1 &= ~OFIFG; // Clear OSCFault flag
for (i = 0xFF; i > 0; i--); // Time for flag to set
}
while ((IFG1 & OFIFG)); // OSCFault flag still set?

BCSCTL2 |= SELM_3; // MCLK= LFXT1 (safe)
P1DIR |= 0x0C; // P1.2 and P1.3 output
P1SEL |= 0x0C; // P1.2 and P1.3 TA1/2 otions
CCR0 = 512-1; // PWM Period
CCTL1 = OUTMOD_7; // CCR1 reset/set
CCR1 = 384; // CCR1 PWM duty cycle
CCTL2 = OUTMOD_7; // CCR2 reset/set
CCR2 = 128; // CCR2 PWM duty cycle
TACTL = TASSEL_1 + MC_1; // ACLK, up mode

_BIS_SR(LPM0_bits); // Enter LPM0
} 答 3: #include <MSP430x14x.h>

void main(void)
{
unsigned int i;
WDTCTL = WDTPW + WDTHOLD; // Stop WDT
BCSCTL1 |= XTS; // ACLK= LFXT1= HF XTAL

do
{
IFG1 &= ~OFIFG; // Clear OSCFault flag
for (i = 0xFF; i > 0; i--); // Time for flag to set
}
while ((IFG1 & OFIFG)); // OSCFault flag still set?

BCSCTL2 |= SELM_3; // MCLK= LFXT1 (safe)
P1DIR |= 0x0C; // P1.2 and P1.3 output
P1SEL |= 0x0C; // P1.2 and P1.3 TA1/2 otions
CCR0 = 128; // PWM Period/2
CCTL1 = OUTMOD_6; // CCR1 toggle/set
CCR1 = 32; // CCR1 PWM duty cycle
CCTL2 = OUTMOD_6; // CCR2 toggle/set
CCR2 = 96; // CCR2 PWM duty cycle
TACTL = TASSEL_1 + MC_3; // ACLK, up-down mode

_BIS_SR(CPUOFF); // Enter LPM0
} 答 4: 我觉的还是输出2路PWM信号? 答 5: 我用MSP430F1121只能调出两路占空比可调的PWM信号。目前也是无法输出三路。 答 6: 怎么可能，不都一样嘛 答 7: 我原来是想用MSP430F1101输出三路占空比可调的PWM信号。采用连续增计数方式，想用CCR0、CCR1、CCR2分别控制输出三路PWM。现改用F133使用Timer_A和Timer_B才分别控制输出三路PWM。 答 8: CCR0都用了就须要软件来调节占空比...在频率高的时候中断比较频繁 答 9: 软件来调节占空比会同时出现多个中断的情况