Tasmota/sonoff/xsns_14_sht3x.ino

163 lines
5.3 KiB
C++
Executable File

/*
xsns_14_sht3x.ino - SHT3X temperature and humidity sensor support for Tasmota
Copyright (C) 2019 Theo Arends
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifdef USE_I2C
#ifdef USE_SHT3X
/*********************************************************************************************\
* SHT3X and SHTC3 - Temperature and Humidity
*
* I2C Address: 0x44, 0x45 or 0x70 (SHTC3)
\*********************************************************************************************/
#define XSNS_14 14
#define SHT3X_ADDR_GND 0x44 // address pin low (GND)
#define SHT3X_ADDR_VDD 0x45 // address pin high (VDD)
#define SHTC3_ADDR 0x70 // address for shtc3 sensor
#define SHT3X_MAX_SENSORS 3
const char kShtTypes[] PROGMEM = "SHT3X|SHT3X|SHTC3";
uint8_t sht3x_addresses[] = { SHT3X_ADDR_GND, SHT3X_ADDR_VDD, SHTC3_ADDR };
uint8_t sht3x_count = 0;
struct SHT3XSTRUCT {
uint8_t address; // I2C bus address
char types[6]; // Sensor type name and address - "SHT3X-0xXX"
} sht3x_sensors[SHT3X_MAX_SENSORS];
bool Sht3xRead(float &t, float &h, uint8_t sht3x_address)
{
unsigned int data[6];
t = NAN;
h = NAN;
Wire.beginTransmission(sht3x_address);
if (SHTC3_ADDR == sht3x_address) {
Wire.write(0x35); // Wake from
Wire.write(0x17); // sleep
Wire.endTransmission();
Wire.beginTransmission(sht3x_address);
Wire.write(0x78); // Disable clock stretching ( I don't think that wire library support clock stretching )
Wire.write(0x66); // High resolution
} else {
Wire.write(0x2C); // Enable clock stretching
Wire.write(0x06); // High repeatability
}
if (Wire.endTransmission() != 0) { // Stop I2C transmission
return false;
}
delay(30); // Timing verified with logic analyzer (10 is to short)
Wire.requestFrom(sht3x_address, (uint8_t)6); // Request 6 bytes of data
for (uint32_t i = 0; i < 6; i++) {
data[i] = Wire.read(); // cTemp msb, cTemp lsb, cTemp crc, humidity msb, humidity lsb, humidity crc
};
t = ConvertTemp((float)((((data[0] << 8) | data[1]) * 175) / 65535.0) - 45);
h = ConvertHumidity((float)((((data[3] << 8) | data[4]) * 100) / 65535.0)); // Set global humidity
return (!isnan(t) && !isnan(h) && (h != 0));
}
/********************************************************************************************/
void Sht3xDetect(void)
{
if (sht3x_count) return;
float t;
float h;
for (uint32_t i = 0; i < SHT3X_MAX_SENSORS; i++) {
if (Sht3xRead(t, h, sht3x_addresses[i])) {
sht3x_sensors[sht3x_count].address = sht3x_addresses[i];
GetTextIndexed(sht3x_sensors[sht3x_count].types, sizeof(sht3x_sensors[sht3x_count].types), i, kShtTypes);
AddLog_P2(LOG_LEVEL_DEBUG, S_LOG_I2C_FOUND_AT, sht3x_sensors[sht3x_count].types, sht3x_sensors[sht3x_count].address);
sht3x_count++;
}
}
}
void Sht3xShow(bool json)
{
if (sht3x_count) {
float t;
float h;
char types[11];
for (uint32_t i = 0; i < sht3x_count; i++) {
if (Sht3xRead(t, h, sht3x_sensors[i].address)) {
char temperature[33];
dtostrfd(t, Settings.flag2.temperature_resolution, temperature);
char humidity[33];
dtostrfd(h, Settings.flag2.humidity_resolution, humidity);
snprintf_P(types, sizeof(types), PSTR("%s%c0x%02X"), sht3x_sensors[i].types, IndexSeparator(), sht3x_sensors[i].address); // "SHT3X-0xXX"
if (json) {
ResponseAppend_P(JSON_SNS_TEMPHUM, types, temperature, humidity);
#ifdef USE_DOMOTICZ
if ((0 == tele_period) && (0 == i)) { // We want the same first sensor to report to Domoticz in case a read is missed
DomoticzTempHumSensor(temperature, humidity);
}
#endif // USE_DOMOTICZ
#ifdef USE_KNX
if (0 == tele_period) {
KnxSensor(KNX_TEMPERATURE, t);
KnxSensor(KNX_HUMIDITY, h);
}
#endif // USE_KNX
#ifdef USE_WEBSERVER
} else {
WSContentSend_PD(HTTP_SNS_TEMP, types, temperature, TempUnit());
WSContentSend_PD(HTTP_SNS_HUM, types, humidity);
#endif // USE_WEBSERVER
}
}
}
}
}
/*********************************************************************************************\
* Interface
\*********************************************************************************************/
bool Xsns14(uint8_t function)
{
bool result = false;
if (i2c_flg) {
switch (function) {
case FUNC_INIT:
Sht3xDetect();
break;
case FUNC_JSON_APPEND:
Sht3xShow(1);
break;
#ifdef USE_WEBSERVER
case FUNC_WEB_SENSOR:
Sht3xShow(0);
break;
#endif // USE_WEBSERVER
}
}
return result;
}
#endif // USE_SHT3X
#endif // USE_I2C