example_detector_distance.c

This is an example on how the Detector Distance API can be used
This example executes as follows:

• Retrieve HAL integration
• Initialize distance detector resources:
  • Create distance detector configuration
  • Update configuration settings
  • Create Distance detector handle
  • Create buffer for detector calibration data
  • Create buffer for sensor data
• Create and calibrate the sensor
• Calibrate the detector
• Measure distances with the detector (loop):
  • Prepare sensor with the detector
  • Measure and wait until a read can be done
  • Process measurement and print the result
  • Handle "calibration_needed" indication
• Cleanup:
  • Destroy detector configuration
  • Destroy detector handle
  • Destroy sensor data buffer
  • Destroy detector calibration data buffer

// Copyright (c) Acconeer AB, 2022-2025
// All rights reserved
// This file is subject to the terms and conditions defined in the file
// 'LICENSES/license_acconeer.txt', (BSD 3-Clause License) which is part
// of this source code package.
 
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
 
#include "acc_definitions_a121.h"
#include "acc_detector_distance.h"
#include "acc_hal_definitions_a121.h"
#include "acc_hal_integration_a121.h"
#include "acc_integration.h"
#include "acc_integration_log.h"
#include "acc_rss_a121.h"
#include "acc_sensor.h"
#include "acc_version.h"
 
/** \example example_detector_distance.c
 * @brief This is an example on how the Detector Distance API can be used
 * @n
 * This example executes as follows:
 *   - Retrieve HAL integration
 *   - Initialize distance detector resources:
 *     + Create distance detector configuration
 *     + Update configuration settings
 *     + Create Distance detector handle
 *     + Create buffer for detector calibration data
 *     + Create buffer for sensor data
 *   - Create and calibrate the sensor
 *   - Calibrate the detector
 *   - Measure distances with the detector (loop):
 *     + Prepare sensor with the detector
 *     + Measure and wait until a read can be done
 *     + Process measurement and print the result
 *     + Handle "calibration_needed" indication
 *   - Cleanup:
 *     + Destroy detector configuration
 *     + Destroy detector handle
 *     + Destroy sensor data buffer
 *     + Destroy detector calibration data buffer
 */
 
typedef enum
{
        DISTANCE_PRESET_CONFIG_NONE = 0,
        DISTANCE_PRESET_CONFIG_BALANCED,
        DISTANCE_PRESET_CONFIG_HIGH_ACCURACY,
} distance_preset_config_t;
 
#define SENSOR_ID (1U)
// 2 seconds should be enough even for long ranges and high signal quality
#define SENSOR_TIMEOUT_MS (2000U)
 
typedef struct
{
        acc_sensor_t                     *sensor;
        acc_detector_distance_config_t   *config;
        acc_detector_distance_handle_t   *handle;
        void                             *buffer;
        uint32_t                          buffer_size;
        uint8_t                          *detector_cal_result_static;
        uint32_t                          detector_cal_result_static_size;
        acc_detector_cal_result_dynamic_t detector_cal_result_dynamic;
} distance_detector_resources_t;
 
static void cleanup(distance_detector_resources_t *resources);
 
static void set_config(acc_detector_distance_config_t *detector_config, distance_preset_config_t preset);
 
static bool initialize_detector_resources(distance_detector_resources_t *resources);
 
static bool do_sensor_calibration(acc_sensor_t *sensor, acc_cal_result_t *sensor_cal_result, void *buffer, uint32_t buffer_size);
 
static bool do_full_detector_calibration(distance_detector_resources_t *resources, const acc_cal_result_t *sensor_cal_result);
 
static bool do_detector_calibration_update(distance_detector_resources_t *resources, const acc_cal_result_t *sensor_cal_result);
 
static bool do_detector_get_next(distance_detector_resources_t  *resources,
                                 const acc_cal_result_t         *sensor_cal_result,
                                 acc_detector_distance_result_t *result);
 
static void print_distance_result(const acc_detector_distance_result_t *result);
 
int acconeer_main(int argc, char *argv[]);
 
int acconeer_main(int argc, char *argv[])
{
        (void)argc;
        (void)argv;
        distance_detector_resources_t resources = {0};
 
        printf("Acconeer software version %s\n", acc_version_get());
 
        const acc_hal_a121_t *hal = acc_hal_rss_integration_get_implementation();
 
        if (!acc_rss_hal_register(hal))
        {
                return EXIT_FAILURE;
        }
 
        resources.config = acc_detector_distance_config_create();
        if (resources.config == NULL)
        {
                printf("acc_detector_distance_config_create() failed\n");
                cleanup(&resources);
                return EXIT_FAILURE;
        }
 
        set_config(resources.config, DISTANCE_PRESET_CONFIG_BALANCED);
 
        if (!initialize_detector_resources(&resources))
        {
                printf("Initializing detector resources failed\n");
                cleanup(&resources);
                return EXIT_FAILURE;
        }
 
        // Print the configuration
        acc_detector_distance_config_log(resources.handle, resources.config);
 
        /* Turn the sensor on */
        acc_hal_integration_sensor_supply_on(SENSOR_ID);
        acc_hal_integration_sensor_enable(SENSOR_ID);
 
        resources.sensor = acc_sensor_create(SENSOR_ID);
        if (resources.sensor == NULL)
        {
                printf("acc_sensor_create() failed\n");
                cleanup(&resources);
                return EXIT_FAILURE;
        }
 
        acc_cal_result_t sensor_cal_result;
 
        if (!do_sensor_calibration(resources.sensor, &sensor_cal_result, resources.buffer, resources.buffer_size))
        {
                printf("Sensor calibration failed\n");
                cleanup(&resources);
                return EXIT_FAILURE;
        }
 
        if (!do_full_detector_calibration(&resources, &sensor_cal_result))
        {
                printf("Detector calibration failed\n");
                cleanup(&resources);
                return EXIT_FAILURE;
        }
 
        while (true)
        {
                acc_detector_distance_result_t result = {0};
 
                if (!do_detector_get_next(&resources, &sensor_cal_result, &result))
                {
                        printf("Could not get next result\n");
                        cleanup(&resources);
                        return EXIT_FAILURE;
                }
 
                /* If "calibration needed" is indicated, the sensor needs to be recalibrated and the detector calibration updated */
                if (result.calibration_needed)
                {
                        printf("Sensor recalibration and detector calibration update needed ... \n");
 
                        if (!do_sensor_calibration(resources.sensor, &sensor_cal_result, resources.buffer, resources.buffer_size))
                        {
                                printf("Sensor calibration failed\n");
                                cleanup(&resources);
                                return EXIT_FAILURE;
                        }
 
                        /* Once the sensor is recalibrated, the detector calibration should be updated and measuring can continue. */
                        if (!do_detector_calibration_update(&resources, &sensor_cal_result))
                        {
                                printf("Detector calibration update failed\n");
                                cleanup(&resources);
                                return EXIT_FAILURE;
                        }
 
                        printf("Sensor recalibration and detector calibration update done!\n");
                }
                else
                {
                        print_distance_result(&result);
                }
        }
 
        cleanup(&resources);
 
        printf("Done!\n");
 
        return EXIT_SUCCESS;
}
 
static void cleanup(distance_detector_resources_t *resources)
{
        acc_hal_integration_sensor_disable(SENSOR_ID);
        acc_hal_integration_sensor_supply_off(SENSOR_ID);
 
        acc_detector_distance_config_destroy(resources->config);
        acc_detector_distance_destroy(resources->handle);
 
        acc_integration_mem_free(resources->buffer);
        acc_integration_mem_free(resources->detector_cal_result_static);
 
        if (resources->sensor != NULL)
        {
                acc_sensor_destroy(resources->sensor);
        }
}
 
static void set_config(acc_detector_distance_config_t *detector_config, distance_preset_config_t preset)
{
        // Add configuration of the detector here
        switch (preset)
        {
                case DISTANCE_PRESET_CONFIG_NONE:
                        // Add configuration of the detector here
                        break;
 
                case DISTANCE_PRESET_CONFIG_BALANCED:
                        acc_detector_distance_config_start_set(detector_config, 0.25f);
                        acc_detector_distance_config_end_set(detector_config, 3.0f);
                        acc_detector_distance_config_max_step_length_set(detector_config, 0U);
                        acc_detector_distance_config_max_profile_set(detector_config, ACC_CONFIG_PROFILE_5);
                        acc_detector_distance_config_reflector_shape_set(detector_config, ACC_DETECTOR_DISTANCE_REFLECTOR_SHAPE_GENERIC);
                        acc_detector_distance_config_peak_sorting_set(detector_config, ACC_DETECTOR_DISTANCE_PEAK_SORTING_STRONGEST);
                        acc_detector_distance_config_threshold_method_set(detector_config, ACC_DETECTOR_DISTANCE_THRESHOLD_METHOD_CFAR);
                        acc_detector_distance_config_threshold_sensitivity_set(detector_config, 0.5f);
                        acc_detector_distance_config_signal_quality_set(detector_config, 15.0f);
                        acc_detector_distance_config_close_range_leakage_cancellation_set(detector_config, false);
                        break;
 
                case DISTANCE_PRESET_CONFIG_HIGH_ACCURACY:
                        acc_detector_distance_config_start_set(detector_config, 0.25f);
                        acc_detector_distance_config_end_set(detector_config, 3.0f);
                        acc_detector_distance_config_max_step_length_set(detector_config, 2U);
                        acc_detector_distance_config_max_profile_set(detector_config, ACC_CONFIG_PROFILE_3);
                        acc_detector_distance_config_reflector_shape_set(detector_config, ACC_DETECTOR_DISTANCE_REFLECTOR_SHAPE_GENERIC);
                        acc_detector_distance_config_peak_sorting_set(detector_config, ACC_DETECTOR_DISTANCE_PEAK_SORTING_STRONGEST);
                        acc_detector_distance_config_threshold_method_set(detector_config, ACC_DETECTOR_DISTANCE_THRESHOLD_METHOD_CFAR);
                        acc_detector_distance_config_threshold_sensitivity_set(detector_config, 0.5f);
                        acc_detector_distance_config_signal_quality_set(detector_config, 20.0f);
                        acc_detector_distance_config_close_range_leakage_cancellation_set(detector_config, false);
                        break;
        }
}
 
static bool initialize_detector_resources(distance_detector_resources_t *resources)
{
        resources->handle = acc_detector_distance_create(resources->config);
        if (resources->handle == NULL)
        {
                printf("acc_detector_distance_create() failed\n");
                return false;
        }
 
        if (!acc_detector_distance_get_sizes(resources->handle, &(resources->buffer_size), &(resources->detector_cal_result_static_size)))
        {
                printf("acc_detector_distance_get_sizes() failed\n");
                return false;
        }
 
        resources->buffer = acc_integration_mem_alloc(resources->buffer_size);
        if (resources->buffer == NULL)
        {
                printf("sensor buffer allocation failed\n");
                return false;
        }
 
        resources->detector_cal_result_static = acc_integration_mem_alloc(resources->detector_cal_result_static_size);
        if (resources->detector_cal_result_static == NULL)
        {
                printf("calibration buffer allocation failed\n");
                return false;
        }
 
        return true;
}
 
static bool do_sensor_calibration(acc_sensor_t *sensor, acc_cal_result_t *sensor_cal_result, void *buffer, uint32_t buffer_size)
{
        bool           status              = false;
        bool           cal_complete        = false;
        const uint16_t calibration_retries = 1U;
 
        // Random disturbances may cause the calibration to fail. At failure, retry at least once.
        for (uint16_t i = 0; !status && (i <= calibration_retries); i++)
        {
                // Reset sensor before calibration by disabling/enabling it
                acc_hal_integration_sensor_disable(SENSOR_ID);
                acc_hal_integration_sensor_enable(SENSOR_ID);
 
                do
                {
                        status = acc_sensor_calibrate(sensor, &cal_complete, sensor_cal_result, buffer, buffer_size);
 
                        if (status && !cal_complete)
                        {
                                status = acc_hal_integration_wait_for_sensor_interrupt(SENSOR_ID, SENSOR_TIMEOUT_MS);
                        }
                } while (status && !cal_complete);
        }
 
        if (status)
        {
                /* Reset sensor after calibration by disabling/enabling it */
                acc_hal_integration_sensor_disable(SENSOR_ID);
                acc_hal_integration_sensor_enable(SENSOR_ID);
        }
 
        return status;
}
 
static bool do_full_detector_calibration(distance_detector_resources_t *resources, const acc_cal_result_t *sensor_cal_result)
{
        bool done = false;
        bool status;
 
        do
        {
                status = acc_detector_distance_calibrate(resources->sensor,
                                                         resources->handle,
                                                         sensor_cal_result,
                                                         resources->buffer,
                                                         resources->buffer_size,
                                                         resources->detector_cal_result_static,
                                                         resources->detector_cal_result_static_size,
                                                         &resources->detector_cal_result_dynamic,
                                                         &done);
 
                if (status && !done)
                {
                        status = acc_hal_integration_wait_for_sensor_interrupt(SENSOR_ID, SENSOR_TIMEOUT_MS);
                }
        } while (status && !done);
 
        return status;
}
 
static bool do_detector_calibration_update(distance_detector_resources_t *resources, const acc_cal_result_t *sensor_cal_result)
{
        bool done = false;
        bool status;
 
        do
        {
                status = acc_detector_distance_update_calibration(resources->sensor,
                                                                  resources->handle,
                                                                  sensor_cal_result,
                                                                  resources->buffer,
                                                                  resources->buffer_size,
                                                                  &resources->detector_cal_result_dynamic,
                                                                  &done);
 
                if (status && !done)
                {
                        status = acc_hal_integration_wait_for_sensor_interrupt(SENSOR_ID, SENSOR_TIMEOUT_MS);
                }
        } while (status && !done);
 
        return status;
}
 
static bool do_detector_get_next(distance_detector_resources_t  *resources,
                                 const acc_cal_result_t         *sensor_cal_result,
                                 acc_detector_distance_result_t *result)
{
        bool result_available = false;
 
        do
        {
                if (!acc_detector_distance_prepare(resources->handle,
                                                   resources->config,
                                                   resources->sensor,
                                                   sensor_cal_result,
                                                   resources->buffer,
                                                   resources->buffer_size))
                {
                        printf("acc_detector_distance_prepare() failed\n");
                        return false;
                }
 
                if (!acc_sensor_measure(resources->sensor))
                {
                        printf("acc_sensor_measure() failed\n");
                        return false;
                }
 
                if (!acc_hal_integration_wait_for_sensor_interrupt(SENSOR_ID, SENSOR_TIMEOUT_MS))
                {
                        printf("Sensor interrupt timeout\n");
                        return false;
                }
 
                if (!acc_sensor_read(resources->sensor, resources->buffer, resources->buffer_size))
                {
                        printf("acc_sensor_read() failed\n");
                        return false;
                }
 
                if (!acc_detector_distance_process(resources->handle,
                                                   resources->buffer,
                                                   resources->detector_cal_result_static,
                                                   &resources->detector_cal_result_dynamic,
                                                   &result_available,
                                                   result))
                {
                        printf("acc_detector_distance_process() failed\n");
                        return false;
                }
        } while (!result_available);
 
        return true;
}
 
static void print_distance_result(const acc_detector_distance_result_t *result)
{
        printf("%d detected distances", result->num_distances);
        if (result->num_distances > 0)
        {
                printf(": ");
 
                for (uint8_t i = 0; i < result->num_distances; i++)
                {
                        printf("%" PRIfloat " m ", ACC_LOG_FLOAT_TO_INTEGER(result->distances[i]));
                }
        }
 
        printf("\n");
}