RGB

[D]

Hi

I have a RGB LED and want to have bellow process for brightness:

Red from o to 100 then Green from 0 to 100 and Blue from 0 to 100.

till now i by bellow code i can go for a white color which seems start from 0 to 100. But what i need is different because i am

unable to do it for 3 colors. I will appereciate if u help me. Moreover i am using demo1 of pwm driver example.

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/** @file
 * @defgroup pwm_example_main main.c
 * @{
 * @ingroup pwm_example
 *
 * @brief PWM Example Application main file.
 *
 * This file contains the source code for a sample application using PWM.
 */

#include <stdio.h>
#include <string.h>
#include "nrf_drv_pwm.h"
#include "app_util_platform.h"
#include "app_error.h"
#include "boards.h"
#include "bsp.h"
#include "app_timer.h"
#include "nrf_drv_clock.h"

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"

#define red 31
#define green 29
#define blue 28

static nrf_drv_pwm_t m_pwm0 = NRF_DRV_PWM_INSTANCE(0);

static uint16_t const              m_demo1_top  = 10000;
static uint16_t const              m_demo1_step = 200;
static uint8_t                     m_demo1_phase;
static nrf_pwm_values_individual_t m_demo1_seq_values;
static nrf_pwm_sequence_t const    m_demo1_seq =
{
    .values.p_individual = &m_demo1_seq_values,
    .length              = NRF_PWM_VALUES_LENGTH(m_demo1_seq_values),
    .repeats             = 0,
    .end_delay           = 0
};

static void demo1_handler(nrf_drv_pwm_evt_type_t event_type)
{
    if (event_type == NRF_DRV_PWM_EVT_FINISHED)
    {
        uint8_t channel    = m_demo1_phase >> 1;
        bool    down       = m_demo1_phase & 1;
        bool    next_phase = false;

        uint16_t * p_channels = (uint16_t *)&m_demo1_seq_values;
        uint16_t value = p_channels[channel];
        if (down)
        {
            value -= m_demo1_step;
            if (value == 0)
            {
                next_phase = true;
            }
        }
        else
        {
            value += m_demo1_step;
            if (value >= m_demo1_top)
            {
                next_phase = true;
            }
        }
        p_channels[channel] = value;

        if (next_phase)
        {
            if (++m_demo1_phase >= 2 * NRF_PWM_CHANNEL_COUNT)
            {
                m_demo1_phase = 0;
            }
        }
    }
}
static void demo1(void)
{

    nrf_drv_pwm_config_t const config0 =
    {
        .output_pins =
        {
        
          red | NRF_DRV_PWM_PIN_INVERTED, // channel 0
          green| NRF_DRV_PWM_PIN_INVERTED, // channel 1
          blue | NRF_DRV_PWM_PIN_INVERTED, // channel 2
        
        },
        .irq_priority = APP_IRQ_PRIORITY_LOWEST,
        .base_clock   = NRF_PWM_CLK_1MHz,
        .count_mode   = NRF_PWM_MODE_UP,
        .top_value    = m_demo1_top,
        .load_mode    = NRF_PWM_LOAD_INDIVIDUAL,
        .step_mode    = NRF_PWM_STEP_AUTO
    };
    APP_ERROR_CHECK(nrf_drv_pwm_init(&m_pwm0, &config0, demo1_handler));

    (void)nrf_drv_pwm_simple_playback(&m_pwm0, &m_demo1_seq, 1,
                                      NRF_DRV_PWM_FLAG_LOOP);
}

int main(void)
{
    APP_ERROR_CHECK(NRF_LOG_INIT(NULL));
  
    demo1();

    for (;;)
    {
       
    }
}

[D]

I just want:

1_LED red fade up then down

2_LED green fade up then down

3_LED blue fade up then down

I know demo1 must do this but i cant see this process in RGB led.

[awneil]

Yes - as already stated, the demo1 program does do exactly that.

But, as I said, it does it on four LEDs - not three.

So does this unwanted "ON" period you're seeing correspond to the fade-up & fade-down time of the 4th LED ... ?

[D]

I eddited the code  for 3 leds and have this problem. so i dont think so it is correspond to 4th led.

[awneil]

OK - so if you run that edited code on the DK, what do you see on the 3 LEDs?

The code neither knows nor cares what colours the LEDs are!

[D]

So for 3 channel:

nrf_drv_pwm_config_t const config0 =
{
.output_pins =
{
red
green
blue
},

and for seq:

m_demo1_seq_values.channel_0 = 0;
m_demo1_seq_values.channel_1 = 0;
m_demo1_seq_values.channel_2 = 0;

is that correct?