-
Notifications
You must be signed in to change notification settings - Fork 2
/
sgp41_i2c.h
134 lines (124 loc) · 5.05 KB
/
sgp41_i2c.h
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
/*
* THIS FILE IS AUTOMATICALLY GENERATED
*
* I2C-Generator: 0.3.0
* Yaml Version: 0.1.0
* Template Version: 0.7.0-62-g3d691f9
*/
/*
* Copyright (c) 2021, Sensirion AG
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* * Redistributions in binary form 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.
*
* * Neither the name of Sensirion AG nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER 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.
*/
#ifndef SGP41_I2C_H
#define SGP41_I2C_H
#ifdef __cplusplus
extern "C" {
#endif
#include "sensirion_config.h"
/**
* sgp41_execute_conditioning() - This command starts the conditioning, i.e.,
* the VOC pixel will be operated at the same temperature as it is by calling
* the sgp41_measure_raw command while the NOx pixel will be operated at a
* different temperature for conditioning. This command returns only the
* measured raw signal of the VOC pixel SRAW_VOC as 2 bytes (+ 1 CRC byte).
*
* WARNING: To avoid damage to the sensing material the conditioning must not
* exceed 10s!
*
* @param default_rh Default conditions for relative humidty.
*
* @param default_t Default conditions for temperature.
*
* @param sraw_voc u16 unsigned integer directly provides the raw signal
* SRAW_VOC in ticks which is proportional to the logarithm of the resistance of
* the sensing element.
*
* @return 0 on success, an error code otherwise
*/
int16_t sgp41_execute_conditioning(uint16_t default_rh, uint16_t default_t,
uint16_t* sraw_voc);
/**
* sgp41_measure_raw_signals() - This command starts/continues the VOC+NOx
* measurement mode
*
* @param relative_humidity Leaves humidity compensation disabled by sending the
* default value 0x8000 (50%RH) or enables humidity compensation when sending
* the relative humidity in ticks (ticks = %RH * 65535 / 100)
*
* @param temperature Leaves humidity compensation disabled by sending the
* default value 0x6666 (25 degC) or enables humidity compensation when sending
* the temperature in ticks (ticks = (degC + 45) * 65535 / 175)
*
* @param sraw_voc u16 unsigned integer directly provides the raw signal
* SRAW_VOC in ticks which is proportional to the logarithm of the resistance of
* the sensing element.
*
* @param sraw_nox u16 unsigned integer directly provides the raw signal
* SRAW_NOX in ticks which is proportional to the logarithm of the resistance of
* the sensing element.
*
* @return 0 on success, an error code otherwise
*/
int16_t sgp41_measure_raw_signals(uint16_t relative_humidity,
uint16_t temperature, uint16_t* sraw_voc,
uint16_t* sraw_nox);
/**
* sgp41_execute_self_test() - This command triggers the built-in self-test
* checking for integrity of both hotplate and MOX material and returns the
* result of this test as 2 bytes
*
* @param test_result 0xXX 0xYY: ignore most significant byte 0xXX. The four
* least significant bits of the least significant byte 0xYY provide information
* if the self-test has or has not passed for each individual pixel. All zero
* mean all tests passed successfully. Check the datasheet for more detailed
* information.
*
* @return 0 on success, an error code otherwise
*/
int16_t sgp41_execute_self_test(uint16_t* test_result);
/**
* sgp41_turn_heater_off() - This command turns the hotplate off and stops the
* measurement. Subsequently, the sensor enters the idle mode.
*
* @return 0 on success, an error code otherwise
*/
int16_t sgp41_turn_heater_off(void);
/**
* sgp41_get_serial_number() - This command provides the decimal serial number
* of the SGP41 chip by returning 3x2 bytes.
*
* @param serial_number 48-bit unique serial number
*
* @return 0 on success, an error code otherwise
*/
int16_t sgp41_get_serial_number(uint16_t* serial_number);
#ifdef __cplusplus
}
#endif
#endif /* SGP41_I2C_H */