timer_playground.c

#include <stdbool.h>
#include <stdint.h>
#include "boards.h"
#include "bsp.h"
#include "app_timer.h"
#include "nordic_common.h"
#include "nrf_error.h"

#include "nrfx_timer.h"


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

#define BUTTON_PREV_ID           0                           /**< Button used to switch the state. */
#define BUTTON_NEXT_ID           1                           /**< Button used to switch the state. */

#define CYCLE_PERIOD             300

static const nrfx_timer_t m_timer0 = NRFX_TIMER_INSTANCE(0);
static const nrfx_timer_t m_timer1 = NRFX_TIMER_INSTANCE(1);
static const nrfx_timer_t m_timer3 = NRFX_TIMER_INSTANCE(3);

static uint8_t state = 0;
static const uint8_t num_states = 3;

void display_leds(uint8_t const val){
    bsp_board_leds_off();
    for(int i = 0; i < 4; i++)
      if((1 << i) & val) bsp_board_led_on(i);
}

static void timer0_event_handler(nrf_timer_event_t event_type, void * p_context)
{
    switch(state)
    {
        case 0:
        case 1:
        case 2:
            break;
    }
}

static void timer1_event_handler(nrf_timer_event_t event_type, void * p_context)
{
    switch(state)
    {
        case 0:
            break;
        case 1:
            nrfx_timer_increment(&m_timer0);
            display_leds(nrfx_timer_capture(&m_timer0, NRF_TIMER_CC_CHANNEL0));
            nrfx_timer_clear(&m_timer1);
            break;
        case 2:
            nrfx_timer_enable(&m_timer3);
            break;
    }
}

static void timer3_event_handler(nrf_timer_event_t event_type, void * p_context)
{
    switch(state)
    {
        case 0:
        case 1:
            break;
        case 2:
            bsp_board_leds_off();
            switch(event_type){
                case NRF_TIMER_EVENT_COMPARE0:
                    bsp_board_led_on(0);
                    break;
                case NRF_TIMER_EVENT_COMPARE1:
                    bsp_board_led_on(1);
                    break;
                case NRF_TIMER_EVENT_COMPARE2:
                    bsp_board_led_on(3);
                    break;
                case NRF_TIMER_EVENT_COMPARE3:
                    bsp_board_led_on(2);
                    break;
                case NRF_TIMER_EVENT_COMPARE4:
                    nrfx_timer_disable(&m_timer3);
                    break;
            }
            break;
    }
}




void bsp_evt_handler(bsp_event_t evt)
{
    uint32_t err_code;
    switch (evt)
    {
        case BSP_EVENT_KEY_0:
            if(state > 0) break;

            nrfx_timer_increment(&m_timer0);
            display_leds(nrfx_timer_capture(&m_timer0, NRF_TIMER_CC_CHANNEL0));
            break;

        case BSP_EVENT_KEY_1:
            state = (state + 1) % num_states;
            break;

        default:
            return;
    }
}


/**@brief Function for initializing low frequency clock.
 */
void clock_initialization()
{
    NRF_CLOCK->LFCLKSRC            = (CLOCK_LFCLKSRC_SRC_Xtal << CLOCK_LFCLKSRC_SRC_Pos);
    NRF_CLOCK->EVENTS_LFCLKSTARTED = 0;
    NRF_CLOCK->TASKS_LFCLKSTART    = 1;

    while (NRF_CLOCK->EVENTS_LFCLKSTARTED == 0)
    {
        // Do nothing.
    }
}


/**@brief Function for initializing bsp module.
 */
void bsp_configuration()
{
    uint32_t err_code;

    err_code = bsp_init(BSP_INIT_LEDS | BSP_INIT_BUTTONS, bsp_evt_handler);
    APP_ERROR_CHECK(err_code);
}


void timer0_initialization(){
        // Check TIMER0 configuration for details.
    nrfx_timer_config_t timer_cfg = NRFX_TIMER_DEFAULT_CONFIG;
    ret_code_t err_code = nrfx_timer_init(&m_timer0, &timer_cfg, timer0_event_handler);
    APP_ERROR_CHECK(err_code);

    nrfx_timer_extended_compare(&m_timer0,
                                   NRF_TIMER_CC_CHANNEL0,
                                   16,
                                   NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
                                   true);

    NRF_LOG_INFO("Timer 0 initialized.");
    NRF_LOG_FLUSH();
    nrfx_timer_enable(&m_timer0);
}

void timer1_initialization(){
    nrfx_timer_config_t timer_cfg = NRFX_TIMER_DEFAULT_CONFIG;
    timer_cfg.bit_width = 3;
    timer_cfg.mode = 0;

    NRF_LOG_INFO("Initializing Timer 1...");
    ret_code_t err_code = nrfx_timer_init(&m_timer1, &timer_cfg, timer1_event_handler);
    APP_ERROR_CHECK(err_code);

    nrfx_timer_extended_compare(&m_timer1,
                                   NRF_TIMER_CC_CHANNEL0,
                                   0x7A12, // At the lowest frequency, this is exactly a second.
                                   NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
                                   true);

    NRF_LOG_INFO("Timer 1 initialized.");
    NRF_LOG_FLUSH();
    nrfx_timer_enable(&m_timer1);
}

void timer2_initialization(){
    // Check TIMER0 configuration for details.
    nrfx_timer_config_t timer_cfg = NRFX_TIMER_DEFAULT_CONFIG;
    timer_cfg.bit_width = 3;
    timer_cfg.mode = 0;

    NRF_LOG_INFO("Initializing Timer 3...");
    ret_code_t err_code = nrfx_timer_init(&m_timer3, &timer_cfg, timer3_event_handler);
    APP_ERROR_CHECK(err_code);


    nrfx_timer_extended_compare(&m_timer3,
                                   NRF_TIMER_CC_CHANNEL0,
                                   nrfx_timer_ms_to_ticks(&m_timer3, CYCLE_PERIOD/5), // At the lowest frequency, this is exactly a second.
                                   NULL,
                                   true);
    nrfx_timer_extended_compare(&m_timer3,
                                   NRF_TIMER_CC_CHANNEL1,
                                   2*nrfx_timer_ms_to_ticks(&m_timer3, CYCLE_PERIOD/5), // At the lowest frequency, this is exactly a second.
                                   NULL,
                                   true);
    nrfx_timer_extended_compare(&m_timer3,
                                   NRF_TIMER_CC_CHANNEL2,
                                   3*nrfx_timer_ms_to_ticks(&m_timer3, CYCLE_PERIOD/5), // At the lowest frequency, this is exactly a second.
                                   NULL,
                                   true);

    nrfx_timer_extended_compare(&m_timer3,
                                   NRF_TIMER_CC_CHANNEL3,
                                   4*nrfx_timer_ms_to_ticks(&m_timer3, CYCLE_PERIOD/5), // At the lowest frequency, this is exactly a second.
                                   NULL,
                                   true);

    nrfx_timer_extended_compare(&m_timer3,
                                   NRF_TIMER_CC_CHANNEL4,
                                   5*nrfx_timer_ms_to_ticks(&m_timer3, CYCLE_PERIOD/5), // At the lowest frequency, this is exactly a second.
                                   NRF_TIMER_SHORT_COMPARE4_CLEAR_MASK,
                                   true);




    NRF_LOG_INFO("Timer 2 initialized.");
    NRF_LOG_FLUSH();  
}

int main(void)
{
    clock_initialization();

    uint32_t err_code = app_timer_init();
    APP_ERROR_CHECK(err_code);

    APP_ERROR_CHECK(NRF_LOG_INIT(NULL));
    NRF_LOG_DEFAULT_BACKENDS_INIT();

    NRF_LOG_INFO("Timer Playground started.");
    NRF_LOG_FLUSH();

    bsp_configuration();

    NRF_LOG_INFO("Bsp configuration done.");
    NRF_LOG_FLUSH();

    timer0_initialization();
    timer1_initialization();
    timer2_initialization();

    // bsp_indication_set(BSP_INDICATE_BONDING);

    while (true)
    {
        NRF_LOG_FLUSH();
        __SEV();
        __WFE();
        __WFE();
    }
}