example_service_calibration_caching.c

This is an example on how the sensor calibration can be cached
The example executes as follows:

- Retrieve and register HAL stuct
- Create config, processing, and sensor instances
- Calibrate and prepare sensor
- Measure, read and process radar data
- Check 'calibration_needed' indication
- If needed either use cached calibration or perform new calibration and store
- Destroy sensor, processing, and config instances

// Copyright (c) Acconeer AB, 2020-2023
// 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_config.h"
#include "acc_definitions_a121.h"
#include "acc_definitions_common.h"
#include "acc_hal_definitions_a121.h"
#include "acc_hal_integration_a121.h"
#include "acc_integration.h"
#include "acc_processing.h"
#include "acc_rss_a121.h"
#include "acc_sensor.h"
#include "acc_version.h"
/** \example example_service_calibration_caching.c
* @brief This is an example on how the sensor calibration can be cached
* @n
* The example executes as follows:
* - Retrieve and register HAL stuct
* - Create config, processing, and sensor instances
* - Calibrate and prepare sensor
* - Measure, read and process radar data
* - Check 'calibration_needed' indication
* - If needed either use cached calibration or perform new calibration and store
* - Destroy sensor, processing, and config instances
*/
#define SENSOR_ID (1U)
#define SENSOR_TIMEOUT_MS (1000U)
#define MAX_DATA_ENTRY_LEN (15U) // "-32000+-32000i" + zero termination
/**
* A sensor calibration is valid at the temperature it was done +- 15 degrees
*
* If the temperature isn't controlled during caching, which is the case in this example,
* the maximum amount of caches needs to be calculated from a temperature difference of 16.
*
* For example
* - A calibration is done at 25 degrees, which means it is valid between 10 and 40 degrees
* - The temperature changes to 41 degrees
* - A new calibration needs to be done at 41 degrees since it is above the valid range for the previous calibration
* - The new calibration is then valid between 26 and 56 degrees
*
* However, if the temperature is controlled, for example in a factory, the maximum amount
* of caches can be calculated from a temperature difference of 30.
*
* For example
* - A calibration is done at 25 degrees, which means it is valid between 10 and 40 degrees
* - The temperature is manually changed to 55 degrees
* - A new calibration can be done which is valid between 40 and 70 degrees
*
* The maximum temperature variation that the application will operate in is assumed to be
* -40 to 85 degrees in this example.
*/
#define MAX_CAL_TEMP_DIFF (16)
#define MAX_TEMP_VARIATION (125)
#define MAX_CACHE_COUNT ((MAX_TEMP_VARIATION / MAX_CAL_TEMP_DIFF) + 1)
// Note that each 'acc_cal_result_t' struct should be suitably aligned for any built-in type
static acc_cal_result_t cal_results[MAX_CACHE_COUNT];
static int16_t cal_temps[MAX_CACHE_COUNT];
static uint16_t curr_cache_count = 0;
static void set_config(acc_config_t *config);
static bool find_cache_index(int16_t temp, uint16_t *cache_index);
static bool get_next_empty_cache_index(uint16_t *cache_index);
static bool add_cache(uint16_t cache_index, int16_t temp);
static bool calibration_caching_and_prepare(acc_sensor_t *sensor,
acc_config_t *config,
void *buffer,
uint32_t buffer_size,
bool temp_known,
int16_t temp);
static void cleanup(acc_config_t *config, acc_processing_t *processing, acc_sensor_t *sensor, void *buffer);
int acconeer_main(int argc, char *argv[]);
int acconeer_main(int argc, char *argv[])
{
(void)argc;
(void)argv;
acc_config_t *config = NULL;
acc_processing_t *processing = NULL;
acc_sensor_t *sensor = NULL;
void *buffer = NULL;
uint32_t buffer_size = 0;
acc_processing_metadata_t proc_meta;
acc_processing_result_t proc_result;
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;
}
config = acc_config_create();
if (config == NULL)
{
printf("acc_config_create() failed\n");
cleanup(config, processing, sensor, buffer);
return EXIT_FAILURE;
}
set_config(config);
// Print the configuration
acc_config_log(config);
processing = acc_processing_create(config, &proc_meta);
if (processing == NULL)
{
printf("acc_processing_create() failed\n");
cleanup(config, processing, sensor, buffer);
return EXIT_FAILURE;
}
if (!acc_rss_get_buffer_size(config, &buffer_size))
{
printf("acc_rss_get_buffer_size() failed\n");
cleanup(config, processing, sensor, buffer);
return EXIT_FAILURE;
}
buffer = acc_integration_mem_alloc(buffer_size);
if (buffer == NULL)
{
printf("buffer allocation failed\n");
cleanup(config, processing, sensor, buffer);
return EXIT_FAILURE;
}
acc_hal_integration_sensor_supply_on(SENSOR_ID);
acc_hal_integration_sensor_enable(SENSOR_ID);
sensor = acc_sensor_create(SENSOR_ID);
if (sensor == NULL)
{
printf("acc_sensor_create() failed\n");
cleanup(config, processing, sensor, buffer);
return EXIT_FAILURE;
}
if (!calibration_caching_and_prepare(sensor, config, buffer, buffer_size, false, 0))
{
printf("calibration_caching_and_prepare() failed\n");
acc_sensor_status(sensor);
cleanup(config, processing, sensor, buffer);
return EXIT_FAILURE;
}
uint32_t update_count = 5U;
for (uint32_t i = 0U; i < update_count; i++)
{
if (!acc_sensor_measure(sensor))
{
printf("acc_sensor_measure failed\n");
acc_sensor_status(sensor);
cleanup(config, processing, sensor, buffer);
return EXIT_FAILURE;
}
if (!acc_hal_integration_wait_for_sensor_interrupt(SENSOR_ID, SENSOR_TIMEOUT_MS))
{
printf("Sensor interrupt timeout\n");
acc_sensor_status(sensor);
cleanup(config, processing, sensor, buffer);
return EXIT_FAILURE;
}
if (!acc_sensor_read(sensor, buffer, buffer_size))
{
printf("acc_sensor_read failed\n");
acc_sensor_status(sensor);
cleanup(config, processing, sensor, buffer);
return EXIT_FAILURE;
}
acc_processing_execute(processing, buffer, &proc_result);
if (proc_result.calibration_needed)
{
printf("New calibration needed due to temperature change\n");
if (!calibration_caching_and_prepare(sensor, config, buffer, buffer_size, true, proc_result.temperature))
{
printf("calibration_caching_and_prepare() failed\n");
acc_sensor_status(sensor);
cleanup(config, processing, sensor, buffer);
return EXIT_FAILURE;
}
}
else
{
printf("IQ data retrieved\n");
}
}
cleanup(config, processing, sensor, buffer);
printf("Application finished OK\n");
return EXIT_SUCCESS;
}
static void set_config(acc_config_t *config)
{
// Add configuration of the sensor here
acc_config_start_point_set(config, 80);
acc_config_num_points_set(config, 160);
}
static bool find_cache_index(int16_t temp, uint16_t *cache_index)
{
bool cache_found = false;
uint16_t min_temp_diff = UINT16_MAX;
// If caches have overlapping temperature ranges, the cache
// with center temperature closest to 'temp' will be chosen
for (uint16_t index = 0; index < curr_cache_count; index++)
{
uint16_t temp_diff = abs(cal_temps[index] - temp);
if (temp_diff < MAX_CAL_TEMP_DIFF && temp_diff < min_temp_diff)
{
min_temp_diff = temp_diff;
*cache_index = index;
cache_found = true;
}
}
return cache_found;
}
static bool get_next_empty_cache_index(uint16_t *cache_index)
{
*cache_index = curr_cache_count;
return curr_cache_count < MAX_CACHE_COUNT;
}
static bool add_cache(uint16_t cache_index, int16_t temp)
{
bool status = false;
if ((cache_index == curr_cache_count) && (cache_index < MAX_CACHE_COUNT))
{
cal_temps[cache_index] = temp;
curr_cache_count++;
status = true;
}
return status;
}
static bool calibration_caching_and_prepare(acc_sensor_t *sensor,
acc_config_t *config,
void *buffer,
uint32_t buffer_size,
bool temp_known,
int16_t temp)
{
bool status = true;
bool use_cache = false;
uint16_t cache_index = 0;
// If temperature is known, there might be a cached calibration result that can be used
if (temp_known)
{
if (find_cache_index(temp, &cache_index))
{
use_cache = true;
}
}
// If no cached calibration can be used, a new calibration should be made
// and the result stored at an empty cache_index
if (!use_cache)
{
printf("New calibration is performed\n");
if (!get_next_empty_cache_index(&cache_index))
{
printf("No empty cache_index to store calibration result\n");
return false;
}
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, &cal_results[cache_index], 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);
acc_cal_info_t cal_info;
acc_sensor_get_cal_info(&cal_results[cache_index], &cal_info);
add_cache(cache_index, cal_info.temperature);
}
}
else
{
printf("Using cached calibration for %u degrees Celsius\n", cal_temps[cache_index]);
}
if (status)
{
status = acc_sensor_prepare(sensor, config, &cal_results[cache_index], buffer, buffer_size);
}
return status;
}
static void cleanup(acc_config_t *config, acc_processing_t *processing, acc_sensor_t *sensor, void *buffer)
{
acc_hal_integration_sensor_disable(SENSOR_ID);
acc_hal_integration_sensor_supply_off(SENSOR_ID);
if (sensor != NULL)
{
acc_sensor_destroy(sensor);
}
if (processing != NULL)
{
acc_processing_destroy(processing);
}
if (config != NULL)
{
acc_config_destroy(config);
}
if (buffer != NULL)
{
acc_integration_mem_free(buffer);
}
}
acc_config_start_point_set
void acc_config_start_point_set(acc_config_t *config, int32_t start_point)
Set the starting point of the sweep.
acc_hal_integration_sensor_supply_off
void acc_hal_integration_sensor_supply_off(acc_sensor_id_t sensor_id)
Power off sensor supply.
Definition: acc_hal_integration_stm32cube_xm.c:104
acc_rss_a121.h
acc_processing_destroy
void acc_processing_destroy(acc_processing_t *handle)
Destroy a processing instance identified with the provided processing handle.
acc_hal_integration_sensor_supply_on
void acc_hal_integration_sensor_supply_on(acc_sensor_id_t sensor_id)
Power on sensor supply.
Definition: acc_hal_integration_stm32cube_xm.c:99
acc_cal_info_t
Information about calibration.
Definition: acc_definitions_a121.h:38
acc_processing_result_t
Result provided by the processing module.
Definition: acc_processing.h:71
SENSOR_TIMEOUT_MS
#define SENSOR_TIMEOUT_MS
Definition: example_service_calibration_caching.c:38
acc_sensor_read
bool acc_sensor_read(const acc_sensor_t *sensor, void *buffer, uint32_t buffer_size)
Read out radar data.
buffer
void * buffer
Definition: i2c_example_cargo.c:40
acc_version.h
acc_rss_get_buffer_size
bool acc_rss_get_buffer_size(const acc_config_t *config, uint32_t *buffer_size)
Get the buffer size needed for the specified config.
acc_config_destroy
void acc_config_destroy(acc_config_t *config)
Destroy a configuration freeing any resources allocated.
acc_cal_result_t
The result from a completed calibration.
Definition: acc_definitions_a121.h:30
acc_processing_execute
void acc_processing_execute(acc_processing_t *handle, void *buffer, acc_processing_result_t *result)
Process the data according to the configuration used in create.
get_next_empty_cache_index
static bool get_next_empty_cache_index(uint16_t *cache_index)
Definition: example_service_calibration_caching.c:254
acc_config_create
acc_config_t * acc_config_create(void)
Create a configuration.
acc_integration.h
config
cargo_config_t config
Definition: i2c_example_cargo.c:34
acc_hal_rss_integration_get_implementation
const acc_hal_a121_t * acc_hal_rss_integration_get_implementation(void)
Get hal implementation reference.
Definition: acc_hal_integration_stm32cube_xm.c:152
acc_integration_mem_alloc
void * acc_integration_mem_alloc(size_t size)
Allocate dynamic memory.
Definition: acc_integration_stm32.c:592
acc_processing_metadata_t
Metadata that will be populated by the processing module during creation.
Definition: acc_processing.h:36
acc_hal_a121_t
Definition: acc_hal_definitions_a121.h:82
acc_rss_hal_register
bool acc_rss_hal_register(const acc_hal_a121_t *hal)
Register an integration.
acc_sensor.h
buffer_size
uint32_t buffer_size
Definition: i2c_example_cargo.c:41
sensor
acc_sensor_t * sensor
Definition: i2c_example_cargo.c:33
add_cache
static bool add_cache(uint16_t cache_index, int16_t temp)
Definition: example_service_calibration_caching.c:261
acc_hal_integration_wait_for_sensor_interrupt
bool acc_hal_integration_wait_for_sensor_interrupt(acc_sensor_id_t sensor_id, uint32_t timeout_ms)
Wait for a sensor interrupt.
Definition: acc_hal_integration_stm32cube_xm.c:130
acconeer_main
int acconeer_main(int argc, char *argv[])
Assembly test example.
Definition: example_service_calibration_caching.c:92
acc_hal_integration_a121.h
acc_version_get
const char * acc_version_get(void)
Get the version of the Acconeer software.
acc_config_t
struct acc_config acc_config_t
Definition: acc_config.h:24
printf
#define printf
Definition: printf.h:60
MAX_CACHE_COUNT
#define MAX_CACHE_COUNT
Definition: example_service_calibration_caching.c:66
acc_sensor_get_cal_info
bool acc_sensor_get_cal_info(const acc_cal_result_t *cal_result, acc_cal_info_t *cal_info)
Gets calibration information from a calibration result.
acc_hal_integration_sensor_enable
void acc_hal_integration_sensor_enable(acc_sensor_id_t sensor_id)
Enable sensor.
Definition: acc_hal_integration_stm32cube_xm.c:109
acc_config_num_points_set
void acc_config_num_points_set(acc_config_t *config, uint16_t num_points)
Set the number of data points to measure.
acc_hal_definitions_a121.h
find_cache_index
static bool find_cache_index(int16_t temp, uint16_t *cache_index)
Definition: example_service_calibration_caching.c:232
cal_results
static acc_cal_result_t cal_results[(((125)/(16))+1)]
Definition: example_service_calibration_caching.c:69
cleanup
static void cleanup(acc_config_t *config, acc_processing_t *processing, acc_sensor_t *sensor, void *buffer)
Definition: example_service_calibration_caching.c:353
acc_hal_integration_sensor_disable
void acc_hal_integration_sensor_disable(acc_sensor_id_t sensor_id)
Disable sensor.
Definition: acc_hal_integration_stm32cube_xm.c:119
acc_processing_t
struct acc_processing_handle acc_processing_t
Definition: acc_processing.h:30
acc_sensor_status
void acc_sensor_status(const acc_sensor_t *sensor)
Check the status of the sensor.
calibration_caching_and_prepare
static bool calibration_caching_and_prepare(acc_sensor_t *sensor, acc_config_t *config, void *buffer, uint32_t buffer_size, bool temp_known, int16_t temp)
Definition: example_service_calibration_caching.c:275
SENSOR_ID
#define SENSOR_ID
Definition: example_service_calibration_caching.c:37
acc_sensor_prepare
bool acc_sensor_prepare(acc_sensor_t *sensor, const acc_config_t *config, const acc_cal_result_t *cal_result, void *buffer, uint32_t buffer_size)
Prepare a sensor to do a measurement.
acc_integration_mem_free
void acc_integration_mem_free(void *ptr)
Free dynamic memory.
Definition: acc_integration_stm32.c:602
acc_definitions_common.h
acc_processing_result_t::temperature
int16_t temperature
Definition: acc_processing.h:89
acc_config_log
void acc_config_log(const acc_config_t *config)
Print a configuration to the log.
acc_config.h
curr_cache_count
static uint16_t curr_cache_count
Definition: example_service_calibration_caching.c:71
acc_sensor_calibrate
bool acc_sensor_calibrate(acc_sensor_t *sensor, bool *cal_complete, acc_cal_result_t *cal_result, void *buffer, uint32_t buffer_size)
Calibrate a sensor.
cal_temps
static int16_t cal_temps[(((125)/(16))+1)]
Definition: example_service_calibration_caching.c:70
acc_processing_result_t::calibration_needed
bool calibration_needed
Definition: acc_processing.h:84
acc_cal_info_t::temperature
int16_t temperature
Definition: acc_definitions_a121.h:40
acc_sensor_measure
bool acc_sensor_measure(acc_sensor_t *sensor)
Start a radar measurement with previously prepared configuration.
acc_processing_create
acc_processing_t * acc_processing_create(const acc_config_t *config, acc_processing_metadata_t *processing_metadata)
Create a processing instance with the provided configuration.
set_config
static void set_config(acc_config_t *config)
Definition: example_service_calibration_caching.c:224
acc_processing.h
acc_sensor_t
struct acc_sensor acc_sensor_t
Definition: acc_sensor.h:31
acc_sensor_destroy
void acc_sensor_destroy(acc_sensor_t *sensor)
Destroy a sensor instance freeing any resources allocated.
acc_definitions_a121.h
MAX_CAL_TEMP_DIFF
#define MAX_CAL_TEMP_DIFF
Definition: example_service_calibration_caching.c:64
acc_sensor_create
acc_sensor_t * acc_sensor_create(acc_sensor_id_t sensor_id)
Create a sensor instance.