Im trying to measure the time between 2 consecutive rising endges (Rising and Falling Edge together) on GPIO continuously but I did not find any leads. will appreciate the support.
Im trying to measure the time between 2 consecutive rising endges (Rising and Falling Edge together) on GPIO continuously but I did not find any leads. will appreciate the support.
after implementing the ppi example I start getting these values. But these values are in ms. How can I increase to nano seconds only the output so that i can capture upto 900 nano seconds
#include <stdint.h>
#include "nrf_delay.h"
#include "app_error.h"
#include "nrf_drv_ppi.h"
#include "nrf_drv_timer.h"
#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"
//nrf_drv_timer_us_to_ticks
#define PPI_EXAMPLE_TIMERS_us_PHASE_SHIFT_DELAY (1) // 1s = 10 * 100ms (Timer 0 interrupt)
#define PPI_EXAMPLE_TIMER0_us_INTERVAL (1) // Timer interval in milliseconds
#define PPI_EXAMPLE_TIMER1_us_INTERVAL (1) // Timer interval in milliseconds
#define PPI_EXAMPLE_TIMER2_us_INTERVAL (1) // Timer interval in milliseconds
static const nrf_drv_timer_t m_timer0 = NRF_DRV_TIMER_INSTANCE(0);
static const nrf_drv_timer_t m_timer1 = NRF_DRV_TIMER_INSTANCE(1);
static const nrf_drv_timer_t m_timer2 = NRF_DRV_TIMER_INSTANCE(2);
static nrf_ppi_channel_t m_ppi_channel1;
static nrf_ppi_channel_t m_ppi_channel2;
static volatile uint32_t m_counter;
static void timer0_event_handler(nrf_timer_event_t event_type, void * p_context)
{
++m_counter;
}
/* Timer event handler. Not used since Timer1 and Timer2 are used only for PPI. */
static void empty_timer_handler(nrf_timer_event_t event_type, void * p_context)
{
}
/** @brief Function for initializing the PPI peripheral.
*/
static void ppi_init(void)
{
uint32_t err_code = NRF_SUCCESS;
err_code = nrf_drv_ppi_init();
APP_ERROR_CHECK(err_code);
/* Configure 1st available PPI channel to stop TIMER0 counter on TIMER1 COMPARE[0] match,
* which is every even number of seconds.
*/
err_code = nrf_drv_ppi_channel_alloc(&m_ppi_channel1);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(m_ppi_channel1,
nrf_drv_timer_event_address_get(&m_timer1,
NRF_TIMER_EVENT_COMPARE0),
nrf_drv_timer_task_address_get(&m_timer0,
NRF_TIMER_TASK_STOP));
APP_ERROR_CHECK(err_code);
/* Configure 2nd available PPI channel to start TIMER0 counter at TIMER2 COMPARE[0] match,
* which is every odd number of seconds.
*/
err_code = nrf_drv_ppi_channel_alloc(&m_ppi_channel2);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(m_ppi_channel2,
nrf_drv_timer_event_address_get(&m_timer2,
NRF_TIMER_EVENT_COMPARE0),
nrf_drv_timer_task_address_get(&m_timer0,
NRF_TIMER_TASK_START));
APP_ERROR_CHECK(err_code);
// Enable both configured PPI channels
err_code = nrf_drv_ppi_channel_enable(m_ppi_channel1);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_enable(m_ppi_channel2);
APP_ERROR_CHECK(err_code);
}
/** @brief Function for Timer 0 initialization.
* @details Timer 0 will be stopped and started by Timer 1 and Timer 2 respectively using PPI.
* It is configured to generate an interrupt every 100ms.
*/
static void timer0_init(void)
{
// Check TIMER0 configuration for details.
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
timer_cfg.frequency = NRF_TIMER_FREQ_16MHz;
ret_code_t err_code = nrf_drv_timer_init(&m_timer0, &timer_cfg, timer0_event_handler);
APP_ERROR_CHECK(err_code);
nrf_drv_timer_extended_compare(&m_timer0,
NRF_TIMER_CC_CHANNEL0,
nrf_drv_timer_ms_to_ticks(&m_timer0,
PPI_EXAMPLE_TIMER0_us_INTERVAL),
NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
true);
}
/** @brief Function for Timer 1 initialization.
* @details Initializes TIMER1 peripheral to generate an event every 2 seconds. The events are
* generated at even numbers of seconds after starting the example (2, 4, 6 ...) and they
* are used to stop TIMER0 via PPI: TIMER1->EVENT_COMPARE[0] triggers TIMER0->TASK_STOP.
*/
static void timer1_init(void)
{
// Check TIMER1 configuration for details.
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
timer_cfg.frequency = NRF_TIMER_FREQ_16MHz;
ret_code_t err_code = nrf_drv_timer_init(&m_timer1, &timer_cfg, empty_timer_handler);
APP_ERROR_CHECK(err_code);
nrf_drv_timer_extended_compare(&m_timer1,
NRF_TIMER_CC_CHANNEL0,
nrf_drv_timer_ms_to_ticks(&m_timer1,
PPI_EXAMPLE_TIMER1_us_INTERVAL),
NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
false);
}
/** @brief Function for Timer 2 initialization.
* @details Initializes TIMER2 peripheral to generate an event every 2 seconds. The events are
* generated at odd numbers of seconds after starting the example (3, 5, 7 ...) and they
* are used to start TIMER0 via PPI: TIMER2->EVENT_COMPARE[0] triggers TIMER0->TASK_START.
*/
static void timer2_init(void)
{
// Check TIMER2 configuration for details.
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
timer_cfg.frequency = NRF_TIMER_FREQ_16MHz;
ret_code_t err_code = nrf_drv_timer_init(&m_timer2, &timer_cfg, empty_timer_handler);
APP_ERROR_CHECK(err_code);
nrf_drv_timer_extended_compare(&m_timer2,
NRF_TIMER_CC_CHANNEL0,
nrf_drv_timer_ms_to_ticks(&m_timer2,
PPI_EXAMPLE_TIMER2_us_INTERVAL),
NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
false);
}
/**
* @brief Function for application main entry.
*/
int main(void)
{
uint32_t old_val = 0;
uint32_t err_code;
err_code = NRF_LOG_INIT(NULL);
APP_ERROR_CHECK(err_code);
NRF_LOG_DEFAULT_BACKENDS_INIT();
ppi_init();
timer0_init(); // Timer used to increase m_counter every 100ms.
timer1_init(); // Timer to generate events on even number of seconds - stopping Timer 0
timer2_init(); // Timer to generate events on odd number of seconds - starting Timer 0
NRF_LOG_INFO("PPI example started.");
// Start clock.
nrf_drv_timer_enable(&m_timer0);
/* Below delay is implemented to ensure that Timer0 interrupt will execute before PPI action.
* Please be aware that such solution was tested only in this simple example code. In case
* of more complex systems with higher level interrupts this may lead to not correct timers
* synchronization.
*/
nrf_delay_us(1);
nrf_drv_timer_enable(&m_timer1);
m_counter = (uint32_t)-PPI_EXAMPLE_TIMERS_us_PHASE_SHIFT_DELAY;
// Timer 2 will start one second after Timer 1 (m_counter will equal 0 after 1s)
// while (m_counter != 0)
// {
// just wait
//}
nrf_drv_timer_enable(&m_timer2);
while (true)
{
uint32_t counter = m_counter;
if (old_val != counter)
{
old_val = counter;
NRF_LOG_INFO("Current count: %u", counter);
NRF_LOG_FLUSH();
}
}
}
/** @} */
#include <stdint.h>
#include "nrf_delay.h"
#include "app_error.h"
#include "nrf_drv_ppi.h"
#include "nrf_drv_timer.h"
#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"
//nrf_drv_timer_us_to_ticks
#define PPI_EXAMPLE_TIMERS_us_PHASE_SHIFT_DELAY (1) // 1s = 10 * 100ms (Timer 0 interrupt)
#define PPI_EXAMPLE_TIMER0_us_INTERVAL (1) // Timer interval in milliseconds
#define PPI_EXAMPLE_TIMER1_us_INTERVAL (1) // Timer interval in milliseconds
#define PPI_EXAMPLE_TIMER2_us_INTERVAL (1) // Timer interval in milliseconds
static const nrf_drv_timer_t m_timer0 = NRF_DRV_TIMER_INSTANCE(0);
static const nrf_drv_timer_t m_timer1 = NRF_DRV_TIMER_INSTANCE(1);
static const nrf_drv_timer_t m_timer2 = NRF_DRV_TIMER_INSTANCE(2);
static nrf_ppi_channel_t m_ppi_channel1;
static nrf_ppi_channel_t m_ppi_channel2;
static volatile uint32_t m_counter;
static void timer0_event_handler(nrf_timer_event_t event_type, void * p_context)
{
++m_counter;
}
/* Timer event handler. Not used since Timer1 and Timer2 are used only for PPI. */
static void empty_timer_handler(nrf_timer_event_t event_type, void * p_context)
{
}
/** @brief Function for initializing the PPI peripheral.
*/
static void ppi_init(void)
{
uint32_t err_code = NRF_SUCCESS;
err_code = nrf_drv_ppi_init();
APP_ERROR_CHECK(err_code);
/* Configure 1st available PPI channel to stop TIMER0 counter on TIMER1 COMPARE[0] match,
* which is every even number of seconds.
*/
err_code = nrf_drv_ppi_channel_alloc(&m_ppi_channel1);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(m_ppi_channel1,
nrf_drv_timer_event_address_get(&m_timer1,
NRF_TIMER_EVENT_COMPARE0),
nrf_drv_timer_task_address_get(&m_timer0,
NRF_TIMER_TASK_STOP));
APP_ERROR_CHECK(err_code);
/* Configure 2nd available PPI channel to start TIMER0 counter at TIMER2 COMPARE[0] match,
* which is every odd number of seconds.
*/
err_code = nrf_drv_ppi_channel_alloc(&m_ppi_channel2);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(m_ppi_channel2,
nrf_drv_timer_event_address_get(&m_timer2,
NRF_TIMER_EVENT_COMPARE0),
nrf_drv_timer_task_address_get(&m_timer0,
NRF_TIMER_TASK_START));
APP_ERROR_CHECK(err_code);
// Enable both configured PPI channels
err_code = nrf_drv_ppi_channel_enable(m_ppi_channel1);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_enable(m_ppi_channel2);
APP_ERROR_CHECK(err_code);
}
/** @brief Function for Timer 0 initialization.
* @details Timer 0 will be stopped and started by Timer 1 and Timer 2 respectively using PPI.
* It is configured to generate an interrupt every 100ms.
*/
static void timer0_init(void)
{
// Check TIMER0 configuration for details.
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
timer_cfg.frequency = NRF_TIMER_FREQ_16MHz;
ret_code_t err_code = nrf_drv_timer_init(&m_timer0, &timer_cfg, timer0_event_handler);
APP_ERROR_CHECK(err_code);
nrf_drv_timer_extended_compare(&m_timer0,
NRF_TIMER_CC_CHANNEL0,
nrf_drv_timer_ms_to_ticks(&m_timer0,
PPI_EXAMPLE_TIMER0_us_INTERVAL),
NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
true);
}
/** @brief Function for Timer 1 initialization.
* @details Initializes TIMER1 peripheral to generate an event every 2 seconds. The events are
* generated at even numbers of seconds after starting the example (2, 4, 6 ...) and they
* are used to stop TIMER0 via PPI: TIMER1->EVENT_COMPARE[0] triggers TIMER0->TASK_STOP.
*/
static void timer1_init(void)
{
// Check TIMER1 configuration for details.
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
timer_cfg.frequency = NRF_TIMER_FREQ_16MHz;
ret_code_t err_code = nrf_drv_timer_init(&m_timer1, &timer_cfg, empty_timer_handler);
APP_ERROR_CHECK(err_code);
nrf_drv_timer_extended_compare(&m_timer1,
NRF_TIMER_CC_CHANNEL0,
nrf_drv_timer_ms_to_ticks(&m_timer1,
PPI_EXAMPLE_TIMER1_us_INTERVAL),
NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
false);
}
/** @brief Function for Timer 2 initialization.
* @details Initializes TIMER2 peripheral to generate an event every 2 seconds. The events are
* generated at odd numbers of seconds after starting the example (3, 5, 7 ...) and they
* are used to start TIMER0 via PPI: TIMER2->EVENT_COMPARE[0] triggers TIMER0->TASK_START.
*/
static void timer2_init(void)
{
// Check TIMER2 configuration for details.
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
timer_cfg.frequency = NRF_TIMER_FREQ_16MHz;
ret_code_t err_code = nrf_drv_timer_init(&m_timer2, &timer_cfg, empty_timer_handler);
APP_ERROR_CHECK(err_code);
nrf_drv_timer_extended_compare(&m_timer2,
NRF_TIMER_CC_CHANNEL0,
nrf_drv_timer_ms_to_ticks(&m_timer2,
PPI_EXAMPLE_TIMER2_us_INTERVAL),
NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
false);
}
/**
* @brief Function for application main entry.
*/
int main(void)
{
uint32_t old_val = 0;
uint32_t err_code;
err_code = NRF_LOG_INIT(NULL);
APP_ERROR_CHECK(err_code);
NRF_LOG_DEFAULT_BACKENDS_INIT();
ppi_init();
timer0_init(); // Timer used to increase m_counter every 100ms.
timer1_init(); // Timer to generate events on even number of seconds - stopping Timer 0
timer2_init(); // Timer to generate events on odd number of seconds - starting Timer 0
NRF_LOG_INFO("PPI example started.");
// Start clock.
nrf_drv_timer_enable(&m_timer0);
/* Below delay is implemented to ensure that Timer0 interrupt will execute before PPI action.
* Please be aware that such solution was tested only in this simple example code. In case
* of more complex systems with higher level interrupts this may lead to not correct timers
* synchronization.
*/
nrf_delay_us(1);
nrf_drv_timer_enable(&m_timer1);
m_counter = (uint32_t)-PPI_EXAMPLE_TIMERS_us_PHASE_SHIFT_DELAY;
// Timer 2 will start one second after Timer 1 (m_counter will equal 0 after 1s)
// while (m_counter != 0)
// {
// just wait
//}
nrf_drv_timer_enable(&m_timer2);
while (true)
{
uint32_t counter = m_counter;
if (old_val != counter)
{
old_val = counter;
NRF_LOG_INFO("Current count: %u", counter);
NRF_LOG_FLUSH();
}
}
}
/** @} */
I changed the frequency from 31250Hz to 16MHz, but resolution did not get affected. The one more thing I did not uses LFCLK (crystal) as this was the optional for custom board.
Hi,
You may try this code instead:
/**
* Copyright (c) 2014 - 2021, Nordic Semiconductor ASA
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form, except as embedded into a Nordic
* Semiconductor ASA integrated circuit in a product or a software update for
* such product, must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution.
*
* 3. Neither the name of Nordic Semiconductor ASA nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* 4. This software, with or without modification, must only be used with a
* Nordic Semiconductor ASA integrated circuit.
*
* 5. Any software provided in binary form under this license must not be reverse
* engineered, decompiled, modified and/or disassembled.
*
* THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <stdint.h>
#include "nrf_delay.h"
#include "app_error.h"
#include "boards.h"
#include "nrf_drv_ppi.h"
#include "nrf_drv_timer.h"
#include "nrf_drv_gpiote.h"
#include "nrf_delay.h"
#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"
/* Signal generator output */
#define SIG_OUT_PIN 26
#define SIG_OUT_INTERVAL_US 1
#define SIG_INPUT_PIN 27
static const nrf_drv_timer_t m_timer1 = NRF_DRV_TIMER_INSTANCE(1);
static const nrf_drv_timer_t m_timer2 = NRF_DRV_TIMER_INSTANCE(2);
static const nrf_drv_timer_t m_timer3 = NRF_DRV_TIMER_INSTANCE(3);
static volatile bool m_sample_pending;
/* Timer event handler. Not used since Timer1 and Timer2 are used only for PPI. */
static void empty_timer_handler(nrf_timer_event_t event_type, void * p_context)
{
}
static void signal_capture_handler(nrf_timer_event_t event_type, void * p_context)
{
uint32_t err_code;
uint32_t timer_ticks;
timer_ticks = nrf_drv_timer_capture(&m_timer3, NRF_TIMER_CC_CHANNEL0);
NRF_LOG_INFO("Signal period: " NRF_LOG_FLOAT_MARKER " us", NRF_LOG_FLOAT((float)timer_ticks/16.0f));
nrf_drv_timer_clear(&m_timer3);
nrf_drv_timer_clear(&m_timer2);
m_sample_pending = false;
nrf_drv_gpiote_in_event_disable(SIG_INPUT_PIN);
}
void in_pin_handler(nrf_drv_gpiote_pin_t pin, nrf_gpiote_polarity_t action)
{
}
static void log_init(void)
{
uint32_t err_code = NRF_LOG_INIT(NULL);
APP_ERROR_CHECK(err_code);
NRF_LOG_DEFAULT_BACKENDS_INIT();
}
static void hf_clock_start(void)
{
/* Start HFXO for better accuracy */
NRF_CLOCK->EVENTS_HFCLKSTARTED = 0;
NRF_CLOCK->TASKS_HFCLKSTART = 1;
while (NRF_CLOCK->EVENTS_HFCLKSTARTED == 0)
{};
}
static void signal_generator_start(void)
{
uint32_t err_code;
uint32_t out_task_addr;
uint32_t timer_evt0_addr;
nrf_ppi_channel_t ppi_channel;
nrf_drv_gpiote_out_config_t signal_out = GPIOTE_CONFIG_OUT_TASK_TOGGLE(true);
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
/* Configure timer and output signal */
err_code = nrf_drv_timer_init(&m_timer1, &timer_cfg, empty_timer_handler);
APP_ERROR_CHECK(err_code);
nrf_drv_timer_extended_compare(&m_timer1,
NRF_TIMER_CC_CHANNEL0,
nrfx_timer_us_to_ticks(&m_timer1, SIG_OUT_INTERVAL_US),
NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
false);
timer_evt0_addr = nrf_drv_timer_compare_event_address_get(&m_timer1,NRF_TIMER_CC_CHANNEL0);
/* Configure GPIOTE task */
err_code = nrf_drv_gpiote_out_init(SIG_OUT_PIN, &signal_out);
APP_ERROR_CHECK(err_code);
out_task_addr = nrf_drv_gpiote_out_task_addr_get(SIG_OUT_PIN);
nrf_drv_gpiote_out_task_enable(SIG_OUT_PIN);
/* Connect timer event to GPIOTE task through PPI */
err_code = nrf_drv_ppi_channel_alloc(&ppi_channel);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(ppi_channel, timer_evt0_addr, out_task_addr);
APP_ERROR_CHECK(err_code);
nrf_drv_ppi_channel_enable(ppi_channel);
/* Start signal generation */
nrf_drv_timer_enable(&m_timer1);
}
static void signal_input_sampling_init(void)
{
uint32_t err_code;
nrf_ppi_channel_t ppi_channel;
uint32_t gpiote_evt_addr;
uint32_t count_task_addr;
uint32_t timer_start_addr;
uint32_t timer_stop_addr;
uint32_t timer_evt0_addr;
uint32_t timer_evt1_addr;
nrf_drv_gpiote_in_config_t input_config = GPIOTE_CONFIG_IN_SENSE_HITOLO(true);
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
err_code = nrf_drv_gpiote_in_init(SIG_INPUT_PIN, &input_config, in_pin_handler);
APP_ERROR_CHECK(err_code);
gpiote_evt_addr = nrf_drv_gpiote_in_event_addr_get(SIG_INPUT_PIN);
timer_cfg.mode = NRF_TIMER_MODE_COUNTER;
err_code = nrf_drv_timer_init(&m_timer2, &timer_cfg, signal_capture_handler);
APP_ERROR_CHECK(err_code);
nrf_drv_timer_compare(&m_timer2,
NRF_TIMER_CC_CHANNEL0,
1,
false);
nrf_drv_timer_compare(&m_timer2,
NRF_TIMER_CC_CHANNEL1,
2,
true);
count_task_addr = nrf_drv_timer_task_address_get(&m_timer2, NRF_TIMER_TASK_COUNT);
timer_evt0_addr = nrf_drv_timer_compare_event_address_get(&m_timer2, NRF_TIMER_CC_CHANNEL0);
timer_evt1_addr = nrf_drv_timer_compare_event_address_get(&m_timer2, NRF_TIMER_CC_CHANNEL1);
nrf_drv_timer_enable(&m_timer2);
timer_cfg.mode = NRF_TIMER_MODE_TIMER;
err_code = nrf_drv_timer_init(&m_timer3, &timer_cfg, empty_timer_handler);
APP_ERROR_CHECK(err_code);
timer_start_addr = nrf_drv_timer_task_address_get(&m_timer3, NRF_TIMER_TASK_START);
timer_stop_addr = nrf_drv_timer_task_address_get(&m_timer3, NRF_TIMER_TASK_STOP);
err_code = nrf_drv_ppi_channel_alloc(&ppi_channel);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(ppi_channel, gpiote_evt_addr, count_task_addr);
APP_ERROR_CHECK(err_code);
nrf_drv_ppi_channel_enable(ppi_channel);
err_code = nrf_drv_ppi_channel_alloc(&ppi_channel);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(ppi_channel, timer_evt0_addr, timer_start_addr);
APP_ERROR_CHECK(err_code);
nrf_drv_ppi_channel_enable(ppi_channel);
err_code = nrf_drv_ppi_channel_alloc(&ppi_channel);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(ppi_channel, timer_evt1_addr, timer_stop_addr);
APP_ERROR_CHECK(err_code);
nrf_drv_ppi_channel_enable(ppi_channel);
}
static void ppi_init(void)
{
uint32_t err_code = nrf_drv_ppi_init();
APP_ERROR_CHECK(err_code);
}
static void gpiote_init(void)
{
uint32_t err_code = nrf_drv_gpiote_init();
APP_ERROR_CHECK(err_code);
}
static void signal_input_sample(void)
{
if (!m_sample_pending)
{
nrf_drv_gpiote_in_event_enable(SIG_INPUT_PIN, false);
m_sample_pending = true;
}
}
/**
* @brief Function for application main entry.
*/
void main(void)
{
hf_clock_start();
log_init();
ppi_init();
gpiote_init();
signal_generator_start();
signal_input_sampling_init();
while (true)
{
if (NRF_LOG_PROCESS() == false)
{
//__WFE();
signal_input_sample();
nrf_delay_ms(1000);
}
}
}
/** @} */
Hi,
You may try this code instead:
/**
* Copyright (c) 2014 - 2021, Nordic Semiconductor ASA
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form, except as embedded into a Nordic
* Semiconductor ASA integrated circuit in a product or a software update for
* such product, must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution.
*
* 3. Neither the name of Nordic Semiconductor ASA nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* 4. This software, with or without modification, must only be used with a
* Nordic Semiconductor ASA integrated circuit.
*
* 5. Any software provided in binary form under this license must not be reverse
* engineered, decompiled, modified and/or disassembled.
*
* THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <stdint.h>
#include "nrf_delay.h"
#include "app_error.h"
#include "boards.h"
#include "nrf_drv_ppi.h"
#include "nrf_drv_timer.h"
#include "nrf_drv_gpiote.h"
#include "nrf_delay.h"
#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"
/* Signal generator output */
#define SIG_OUT_PIN 26
#define SIG_OUT_INTERVAL_US 1
#define SIG_INPUT_PIN 27
static const nrf_drv_timer_t m_timer1 = NRF_DRV_TIMER_INSTANCE(1);
static const nrf_drv_timer_t m_timer2 = NRF_DRV_TIMER_INSTANCE(2);
static const nrf_drv_timer_t m_timer3 = NRF_DRV_TIMER_INSTANCE(3);
static volatile bool m_sample_pending;
/* Timer event handler. Not used since Timer1 and Timer2 are used only for PPI. */
static void empty_timer_handler(nrf_timer_event_t event_type, void * p_context)
{
}
static void signal_capture_handler(nrf_timer_event_t event_type, void * p_context)
{
uint32_t err_code;
uint32_t timer_ticks;
timer_ticks = nrf_drv_timer_capture(&m_timer3, NRF_TIMER_CC_CHANNEL0);
NRF_LOG_INFO("Signal period: " NRF_LOG_FLOAT_MARKER " us", NRF_LOG_FLOAT((float)timer_ticks/16.0f));
nrf_drv_timer_clear(&m_timer3);
nrf_drv_timer_clear(&m_timer2);
m_sample_pending = false;
nrf_drv_gpiote_in_event_disable(SIG_INPUT_PIN);
}
void in_pin_handler(nrf_drv_gpiote_pin_t pin, nrf_gpiote_polarity_t action)
{
}
static void log_init(void)
{
uint32_t err_code = NRF_LOG_INIT(NULL);
APP_ERROR_CHECK(err_code);
NRF_LOG_DEFAULT_BACKENDS_INIT();
}
static void hf_clock_start(void)
{
/* Start HFXO for better accuracy */
NRF_CLOCK->EVENTS_HFCLKSTARTED = 0;
NRF_CLOCK->TASKS_HFCLKSTART = 1;
while (NRF_CLOCK->EVENTS_HFCLKSTARTED == 0)
{};
}
static void signal_generator_start(void)
{
uint32_t err_code;
uint32_t out_task_addr;
uint32_t timer_evt0_addr;
nrf_ppi_channel_t ppi_channel;
nrf_drv_gpiote_out_config_t signal_out = GPIOTE_CONFIG_OUT_TASK_TOGGLE(true);
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
/* Configure timer and output signal */
err_code = nrf_drv_timer_init(&m_timer1, &timer_cfg, empty_timer_handler);
APP_ERROR_CHECK(err_code);
nrf_drv_timer_extended_compare(&m_timer1,
NRF_TIMER_CC_CHANNEL0,
nrfx_timer_us_to_ticks(&m_timer1, SIG_OUT_INTERVAL_US),
NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK,
false);
timer_evt0_addr = nrf_drv_timer_compare_event_address_get(&m_timer1,NRF_TIMER_CC_CHANNEL0);
/* Configure GPIOTE task */
err_code = nrf_drv_gpiote_out_init(SIG_OUT_PIN, &signal_out);
APP_ERROR_CHECK(err_code);
out_task_addr = nrf_drv_gpiote_out_task_addr_get(SIG_OUT_PIN);
nrf_drv_gpiote_out_task_enable(SIG_OUT_PIN);
/* Connect timer event to GPIOTE task through PPI */
err_code = nrf_drv_ppi_channel_alloc(&ppi_channel);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(ppi_channel, timer_evt0_addr, out_task_addr);
APP_ERROR_CHECK(err_code);
nrf_drv_ppi_channel_enable(ppi_channel);
/* Start signal generation */
nrf_drv_timer_enable(&m_timer1);
}
static void signal_input_sampling_init(void)
{
uint32_t err_code;
nrf_ppi_channel_t ppi_channel;
uint32_t gpiote_evt_addr;
uint32_t count_task_addr;
uint32_t timer_start_addr;
uint32_t timer_stop_addr;
uint32_t timer_evt0_addr;
uint32_t timer_evt1_addr;
nrf_drv_gpiote_in_config_t input_config = GPIOTE_CONFIG_IN_SENSE_HITOLO(true);
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
err_code = nrf_drv_gpiote_in_init(SIG_INPUT_PIN, &input_config, in_pin_handler);
APP_ERROR_CHECK(err_code);
gpiote_evt_addr = nrf_drv_gpiote_in_event_addr_get(SIG_INPUT_PIN);
timer_cfg.mode = NRF_TIMER_MODE_COUNTER;
err_code = nrf_drv_timer_init(&m_timer2, &timer_cfg, signal_capture_handler);
APP_ERROR_CHECK(err_code);
nrf_drv_timer_compare(&m_timer2,
NRF_TIMER_CC_CHANNEL0,
1,
false);
nrf_drv_timer_compare(&m_timer2,
NRF_TIMER_CC_CHANNEL1,
2,
true);
count_task_addr = nrf_drv_timer_task_address_get(&m_timer2, NRF_TIMER_TASK_COUNT);
timer_evt0_addr = nrf_drv_timer_compare_event_address_get(&m_timer2, NRF_TIMER_CC_CHANNEL0);
timer_evt1_addr = nrf_drv_timer_compare_event_address_get(&m_timer2, NRF_TIMER_CC_CHANNEL1);
nrf_drv_timer_enable(&m_timer2);
timer_cfg.mode = NRF_TIMER_MODE_TIMER;
err_code = nrf_drv_timer_init(&m_timer3, &timer_cfg, empty_timer_handler);
APP_ERROR_CHECK(err_code);
timer_start_addr = nrf_drv_timer_task_address_get(&m_timer3, NRF_TIMER_TASK_START);
timer_stop_addr = nrf_drv_timer_task_address_get(&m_timer3, NRF_TIMER_TASK_STOP);
err_code = nrf_drv_ppi_channel_alloc(&ppi_channel);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(ppi_channel, gpiote_evt_addr, count_task_addr);
APP_ERROR_CHECK(err_code);
nrf_drv_ppi_channel_enable(ppi_channel);
err_code = nrf_drv_ppi_channel_alloc(&ppi_channel);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(ppi_channel, timer_evt0_addr, timer_start_addr);
APP_ERROR_CHECK(err_code);
nrf_drv_ppi_channel_enable(ppi_channel);
err_code = nrf_drv_ppi_channel_alloc(&ppi_channel);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_ppi_channel_assign(ppi_channel, timer_evt1_addr, timer_stop_addr);
APP_ERROR_CHECK(err_code);
nrf_drv_ppi_channel_enable(ppi_channel);
}
static void ppi_init(void)
{
uint32_t err_code = nrf_drv_ppi_init();
APP_ERROR_CHECK(err_code);
}
static void gpiote_init(void)
{
uint32_t err_code = nrf_drv_gpiote_init();
APP_ERROR_CHECK(err_code);
}
static void signal_input_sample(void)
{
if (!m_sample_pending)
{
nrf_drv_gpiote_in_event_enable(SIG_INPUT_PIN, false);
m_sample_pending = true;
}
}
/**
* @brief Function for application main entry.
*/
void main(void)
{
hf_clock_start();
log_init();
ppi_init();
gpiote_init();
signal_generator_start();
signal_input_sampling_init();
while (true)
{
if (NRF_LOG_PROCESS() == false)
{
//__WFE();
signal_input_sample();
nrf_delay_ms(1000);
}
}
}
/** @} */