Hello all,
I have created a BLE application on nRF52 PCA10040 devboard with S132 SD, in which I would like to use a PWM with the PWM_Driver. My pwm source code as below wants to control an RGB LED on GPIO outputs:
#define TOPVALUE 1000 /* Value up to which the pulse generator counter counts */
static nrf_drv_pwm_t pwm = NRF_DRV_PWM_INSTANCE(1);
static nrf_pwm_values_individual_t seq_values_pwm; /* Duty cycle values */
static nrf_pwm_sequence_t const seq_pwm = /* Sequence of duty cycle values */
{
.values.p_individual = &seq_values_pwm,
.length = NRF_PWM_VALUES_LENGTH(seq_values_pwm),
.repeats = 0,
.end_delay = 0
};
void PWM_Init_f(void){
ret_code_t err_code;
nrf_drv_pwm_config_t const config_pwm =
{
.output_pins =
{
GPIO_O_PWM_RGB_R | NRF_DRV_PWM_PIN_INVERTED, /* Channel 0 - RED */
GPIO_O_PWM_RGB_G | NRF_DRV_PWM_PIN_INVERTED, /* Channel 1 - GREEN */
GPIO_O_PWM_RGB_B | NRF_DRV_PWM_PIN_INVERTED, /* Channel 2 - BLUE */
GPIO_O_PWM_W | NRF_DRV_PWM_PIN_INVERTED /* Channel 3 - WHITE */
},
.irq_priority = APP_IRQ_PRIORITY_LOW,
.base_clock = NRF_PWM_CLK_1MHz, /* Base Clock */
.count_mode = NRF_PWM_MODE_UP,
.top_value = TOPVALUE,
.load_mode = NRF_PWM_LOAD_INDIVIDUAL,
.step_mode = NRF_PWM_STEP_AUTO
};
err_code = nrf_drv_pwm_init(&pwm, &config_pwm, NULL);
APP_ERROR_CHECK(err_code);
}
void PWM_Update_f(int16_t dutyR, int16_t dutyG, int16_t dutyB, int16_t dutyW)
{
/* TOPVALUE - : because the LEDs are woring with negative logic */
seq_values_pwm.channel_0 = TOPVALUE - dutyR;
seq_values_pwm.channel_1 = TOPVALUE - dutyG;
seq_values_pwm.channel_2 = TOPVALUE - dutyB;
seq_values_pwm.channel_3 = TOPVALUE - dutyW;
nrf_drv_pwm_simple_playback(&pwm, &seq_pwm, 1, NRF_DRV_PWM_FLAG_STOP);
}
And it is triggered in void main() while a button is pressed:
...
PWM_Init_f();
while (true)
{
sd_app_evt_wait();
if(nrf_gpio_pin_read(GPIO_I_BUTTON_4) == BUTTON_PRESSED)
{
PWM_Update_f(100, 200, 500, 1000);
}
}
I detect the signals with an oscilloscope on GPIO output, and I always get 50 Hz (20 msec) periods between the edges. Do you know what I did wrong? I would like to have more than 120 Hz period between the edges because of dimming an RGB LED. How is it possible?
Thank you in advance!
Regards,
Daniel
