Max PWM period is 1.3ms

[jjvema]

I'm trying to use a servo and my datasshet says that, to get 180 degrees, I need as period 20 ms, but the Minnowboard Turbot only is capable to give 1.3 ms as maximun.

I have use same servo with Raspberry Pi, and I reached 180 degrees.

This is the datasheet: https://www.electronicoscaldas.com/datasheet/MG996R_Tower-Pro.pdf And this is my example:

include "mraa.h"

include "mraa/gpio.h"

include "mraa/pwm.h"

include

include

include

include

include

static volatile mraa_pwm_context pwm = NULL;

volatile sig_atomic_t flag = 1;

int main(int argc, char *argv[]){ mraa_result_t status = MRAA_SUCCESS; float value = 0.0f; float output;

/* initialize mraa for the platform (not needed most of the times) */
mraa_init();

mraa_pwm_close(pwm);

pwm = mraa_pwm_init(22);
if (pwm == NULL) {
    fprintf(stderr, "Failed to initialize PWM\n");
    mraa_deinit();
    return EXIT_FAILURE;
}

/* set PWM period */
status = mraa_pwm_period_us(pwm, 20000);

if (status != MRAA_SUCCESS) {
    fprintf(stderr, "Error PWM period_ms\n");
    return EXIT_FAILURE;
}

/ enable PWM /

status = mraa_pwm_enable(pwm, 1);
if (status != MRAA_SUCCESS) {
    fprintf(stderr, "Error PWM enable\n");
    return EXIT_FAILURE;
}

while (flag) {
    value = value + 0.01f;
    mraa_pwm_write(pwm, value);

    usleep(50000);

    if (value >= 1.0f) {
        value = 0.0f;
    }
    /* read PWM duty cyle */
    output = mraa_pwm_read(pwm);
    fprintf(stdout, "PWM value is %f\n", output);

} / close PWM / mraa_pwm_close(pwm); }

How I can reach 20ms as period?

Regards