LAUNCHXL-CC1352P: pwm高电平与gpio直接输出高电平，电压值不同。

运行官方例程empty,点亮redLED代码如下。

void *mainThread(void *arg0)
{
    /* 1 second delay */
    uint32_t time = 1;

    /* Call driver init functions */
    GPIO_init();
    // I2C_init();
    // SPI_init();
    // UART_init();
    // Watchdog_init();

    /* Configure the LED pin */
    GPIO_setConfig(CONFIG_GPIO_LED_0, GPIO_CFG_OUT_STD | GPIO_CFG_OUT_LOW);

    /* Turn on user LED */
    GPIO_write(CONFIG_GPIO_LED_0, CONFIG_GPIO_LED_ON);

    while (1) {
//        sleep(time);
//        GPIO_toggle(CONFIG_GPIO_LED_0);
    }
}

驱动强度如图：

测得LED电压为2.52v

更改驱动能力后电压不变。

巡行官方例程pwmled2

void *mainThread(void *arg0)
{
    /* Period and duty in microseconds */
    uint16_t   pwmPeriod = 3000;
    uint16_t   duty = 0;
    uint16_t   dutyInc = 100;

    /* Sleep time in microseconds */
    uint32_t   time = 50000;
    PWM_Handle pwm1 = NULL;
    PWM_Handle pwm2 = NULL;
    PWM_Params params;

    /* Call driver init functions. */
    PWM_init();

    PWM_Params_init(&params);
    params.dutyUnits = PWM_DUTY_US;
    params.dutyValue = 0;
    params.periodUnits = PWM_PERIOD_US;
    params.periodValue = pwmPeriod;
    pwm1 = PWM_open(CONFIG_PWM_0, &params);
    if (pwm1 == NULL) {
        /* CONFIG_PWM_0 did not open */
        while (1);
    }

    PWM_start(pwm1);

    pwm2 = PWM_open(CONFIG_PWM_1, &params);
    if (pwm2 == NULL) {
        /* CONFIG_PWM_0 did not open */
        while (1);
    }

    PWM_start(pwm2);

    /* Loop forever incrementing the PWM duty */
    while (1) {
        PWM_setDuty(pwm1, duty);

        PWM_setDuty(pwm2, duty);

        duty = (duty + dutyInc);

        if (duty == pwmPeriod || (!duty)) {//控制占空比递增递减
            dutyInc = - dutyInc;
        }

        usleep(time);
    }
}

驱动强度如图：

测得redLED波形如下：

高电平电压达到3v

测试期间测试点没有做修改，为什么同一个LED，驱动强度相同的情况下，PWM的电压能达到3v,GPIO只能达到2.5v，gpio驱动强度提高，电压也不变。