29 lines
1.0 KiB
C
29 lines
1.0 KiB
C
/** library to query measurements from Aosong DHT22 (aka. AM2302) temperature and relative humidity sensor
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* @file
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* @author King Kévin <kingkevin@cuvoodoo.info>
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* @copyright SPDX-License-Identifier: GPL-3.0-or-later
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* @date 2017-2020
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* @note peripherals used: timer channel @ref sensor_dht22_timer (add external pull-up resistor)
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*/
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#pragma once
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/** a measurement response has been received */
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extern volatile bool sensor_dht22_measurement_received;
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/** measurement returned by sensor */
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struct sensor_dht22_measurement_t {
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float humidity; /**< relative humidity in %RH (0-100) */
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float temperature; /**< temperature in °C (-40-80) */
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};
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/** setup peripherals to communicate with sensor */
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void sensor_dht22_setup(void);
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/** request measurement from sensor
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* @return request started successfully
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*/
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bool sensor_dht22_measurement_request(void);
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/** decode received measurement
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* @return decoded measurement (0xff,0xff if invalid)
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*/
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struct sensor_dht22_measurement_t sensor_dht22_measurement_decode(void);
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