Pwm minimum frequency setting

[muyang]

hi, I would like to use pwm to output the 1HZ waveform to drive the motor, but when I set the frequency to be 1HZ, I can not find the device and cause 51822 to reset. This is my code:

    Motor_Pwm_Init(1000000,1,1);
    Motor_Duty_Set(50,50);

    void Motor_Pwm_Init(uint32_t freq,uint32_t MotorLeft_Polarity,uint32_t MotorRight_Polarity)
{

	uint32_t err_code;
	
	app_pwm_disable(&PWM1);
	app_pwm_uninit(&PWM1);
	app_pwm_config_t pwm1_cfg = APP_PWM_DEFAULT_CONFIG_2CH(freq,MOTOR_LEFT_PIN,MOTOT_RIGHT_PIN);   //set pwm frequency	
	
	pwm1_cfg.pin_polarity[0] = MotorLeft_Polarity;					//Polarity of active state on pin.
    pwm1_cfg.pin_polarity[1] = MotorRight_Polarity;
	
	err_code = app_pwm_init(&PWM1,&pwm1_cfg,NULL);																						//  Init the PWM
    APP_ERROR_CHECK(err_code);

	app_pwm_enable(&PWM1);	
	
}

    uint8_t Motor_Duty_Set(uint32_t DutyLeft,uint32_t DutyRight)
{
	uint8_t TimeOut = 0;
	wdt_feed();
	while (app_pwm_channel_duty_set(&PWM1,(uint8_t) 0, DutyLeft) == NRF_ERROR_BUSY)
	{
		
	}
}

[muyang]

I have been tested to find the minimum frequency can be set to 4HZ, I would like to change with a small time found 51822 reset

[muyang]

I want to output 1HZ what should i do?

[Sigurd]

Hi,

I get 1 Hz with the code you posted. Note that you will only get 1 Hz on the MOTOR_LEFT_PIN since you are only setting the duty cycle to 50% on that pin/channel.

You can modify the Motor_Duty_Set() function to also set the duty cycle for the MOTOT_RIGHT_PIN pin/channel like this:

uint8_t Motor_Duty_Set(uint32_t DutyLeft,uint32_t DutyRight)
{
    uint8_t TimeOut = 0;
    wdt_feed();
    while (app_pwm_channel_duty_set(&PWM1,(uint8_t) 0, DutyLeft) == NRF_ERROR_BUSY)
    {

    }

    while (app_pwm_channel_duty_set(&PWM1,(uint8_t) 1, DutyLeft) == NRF_ERROR_BUSY)
    {

    }

}

[muyang]

Freq this parameter you fill how much? I really can not run here when the 1HZ

[muyang]

Can you send me your project