ultrasonic

Data Structures
struct	ultrasonic_sensor_t

Macros
#define	ESP_ERR_ULTRASONIC_PING   0x200
#define	ESP_ERR_ULTRASONIC_PING_TIMEOUT   0x201
#define	ESP_ERR_ULTRASONIC_ECHO_TIMEOUT   0x202

Functions
esp_err_t	ultrasonic_init (const ultrasonic_sensor_t *dev)
	Init ranging module.
esp_err_t	ultrasonic_measure_raw (const ultrasonic_sensor_t *dev, uint32_t max_time_us, uint32_t *time_us)
	Measure time between ping and echo.
esp_err_t	ultrasonic_measure (const ultrasonic_sensor_t *dev, float max_distance, float *distance)
	Measure distance in meters.
esp_err_t	ultrasonic_measure_cm (const ultrasonic_sensor_t *dev, uint32_t max_distance, uint32_t *distance)
	Measure distance in centimeters.
esp_err_t	ultrasonic_measure_temp_compensated (const ultrasonic_sensor_t *dev, float max_distance, float *distance, float temperature_c)
	Measure distance in meters with temperature compensation.
esp_err_t	ultrasonic_measure_cm_temp_compensated (const ultrasonic_sensor_t *dev, uint32_t max_distance, uint32_t *distance, float temperature_c)
	Measure distance in centimeters with temperature compensation.

Detailed Description

ESP-IDF driver for ultrasonic range meters, e.g. HC-SR04, HY-SRF05 and so on

Ported from esp-open-rtos

Copyright (c) 2016 Ruslan V. Uss uncle.nosp@m.rus@.nosp@m.gmail.nosp@m..com

BSD Licensed as described in the file LICENSE

Function Documentation

ultrasonic_init()

esp_err_t ultrasonic_init

(

const ultrasonic_sensor_t *

dev

)

Init ranging module.

Parameters

dev	Pointer to the device descriptor

Returns

ESP_OK on success

ultrasonic_measure()

esp_err_t ultrasonic_measure	(	const ultrasonic_sensor_t *	dev,
		float	max_distance,
		float *	distance )

Measure distance in meters.

Parameters

	dev	Pointer to the device descriptor
	max_distance	Maximal distance to measure, meters
[out]	distance	Distance in meters

Returns

ESP_OK on success, otherwise:

• ESP_ERR_ULTRASONIC_PING - Invalid state (previous ping is not ended)
• ESP_ERR_ULTRASONIC_PING_TIMEOUT - Device is not responding
• ESP_ERR_ULTRASONIC_ECHO_TIMEOUT - Distance is too big or wave is scattered

ultrasonic_measure_cm()

esp_err_t ultrasonic_measure_cm	(	const ultrasonic_sensor_t *	dev,
		uint32_t	max_distance,
		uint32_t *	distance )

Measure distance in centimeters.

Parameters

	dev	Pointer to the device descriptor
	max_distance	Maximal distance to measure, centimeters
[out]	distance	Distance in centimeters

Returns

ESP_OK on success, otherwise:

• ESP_ERR_ULTRASONIC_PING - Invalid state (previous ping is not ended)
• ESP_ERR_ULTRASONIC_PING_TIMEOUT - Device is not responding
• ESP_ERR_ULTRASONIC_ECHO_TIMEOUT - Distance is too big or wave is scattered

ultrasonic_measure_cm_temp_compensated()

esp_err_t ultrasonic_measure_cm_temp_compensated	(	const ultrasonic_sensor_t *	dev,
		uint32_t	max_distance,
		uint32_t *	distance,
		float	temperature_c )

Measure distance in centimeters with temperature compensation.

Similar to ultrasonic_measure_temp_compensated but provides the distance in centimeters. It factors in the temperature of the air for more accurate measurements across a range of environmental conditions.

Parameters

	dev	Pointer to the device descriptor
	max_distance	Maximal distance to measure, centimeters
[out]	distance	Distance in centimeters
	temperature_c	Current air temperature in degrees Celsius

Returns

ESP_OK on success, otherwise:

• ESP_ERR_ULTRASONIC_PING - Invalid state (previous ping is not ended)
• ESP_ERR_ULTRASONIC_PING_TIMEOUT - Device is not responding
• ESP_ERR_ULTRASONIC_ECHO_TIMEOUT - Distance is too big or wave is scattered

ultrasonic_measure_raw()

esp_err_t ultrasonic_measure_raw	(	const ultrasonic_sensor_t *	dev,
		uint32_t	max_time_us,
		uint32_t *	time_us )

Measure time between ping and echo.

Parameters

	dev	Pointer to the device descriptor
	max_time_us	Maximal time to wait for echo
[out]	time_us	Time, us

Returns

ESP_OK on success, otherwise:

• ESP_ERR_ULTRASONIC_PING - Invalid state (previous ping is not ended)
• ESP_ERR_ULTRASONIC_PING_TIMEOUT - Device is not responding
• ESP_ERR_ULTRASONIC_ECHO_TIMEOUT - Distance is too big or wave is scattered

ultrasonic_measure_temp_compensated()

esp_err_t ultrasonic_measure_temp_compensated	(	const ultrasonic_sensor_t *	dev,
		float	max_distance,
		float *	distance,
		float	temperature_c )

Measure distance in meters with temperature compensation.

This function measures the distance by taking into account the temperature of the air, which affects the speed of sound. This method improves the accuracy of measurements in various environmental conditions.

Parameters

	dev	Pointer to the device descriptor
	max_distance	Maximal distance to measure, meters
[out]	distance	Distance in meters
	temperature_c	Current air temperature in degrees Celsius

Returns

ESP_OK on success, otherwise:

• ESP_ERR_ULTRASONIC_PING - Invalid state (previous ping is not ended)
• ESP_ERR_ULTRASONIC_PING_TIMEOUT - Device is not responding
• ESP_ERR_ULTRASONIC_ECHO_TIMEOUT - Distance is too big or wave is scattered