// ----------------------------------------------------------------------------- // SHT3X Sensor over I2C (Wemos) // Copyright (C) 2017-2019 by Xose PĂ©rez // ----------------------------------------------------------------------------- #if SENSOR_SUPPORT && SHT3X_I2C_SUPPORT #pragma once #undef I2C_SUPPORT #define I2C_SUPPORT 1 // Explicitly request I2C support. #include #include "../utils.h" #include "I2CSensor.h" class SHT3XI2CSensor : public I2CSensor { public: // --------------------------------------------------------------------- // Public // --------------------------------------------------------------------- SHT3XI2CSensor(): I2CSensor() { _sensor_id = SENSOR_SHT3X_I2C_ID; _count = 2; } // --------------------------------------------------------------------- // Sensor API // --------------------------------------------------------------------- // Initialization method, must be idempotent void begin() { if (!_dirty) return; // I2C auto-discover unsigned char addresses[] = {0x45}; _address = _begin_i2c(_address, sizeof(addresses), addresses); if (_address == 0) return; _ready = true; _dirty = false; } // Descriptive name of the sensor String description() { char buffer[25]; snprintf(buffer, sizeof(buffer), "SHT3X @ I2C (0x%02X)", _address); return String(buffer); } // Type for slot # index unsigned char type(unsigned char index) { if (index == 0) return MAGNITUDE_TEMPERATURE; if (index == 1) return MAGNITUDE_HUMIDITY; return MAGNITUDE_NONE; } // Pre-read hook (usually to populate registers with up-to-date data) void pre() { _error = SENSOR_ERROR_OK; unsigned char buffer[6]; i2c_write_uint8(_address, 0x2C, 0x06); nice_delay(500); i2c_read_buffer(_address, buffer, 6); // cTemp msb, cTemp lsb, cTemp crc, humidity msb, humidity lsb, humidity crc _temperature = ((((buffer[0] * 256.0) + buffer[1]) * 175) / 65535.0) - 45; _humidity = ((((buffer[3] * 256.0) + buffer[4]) * 100) / 65535.0); } // Current value for slot # index double value(unsigned char index) { if (index == 0) return _temperature; if (index == 1) return _humidity; return 0; } protected: double _temperature = 0; unsigned char _humidity = 0; }; #endif // SENSOR_SUPPORT && SHT3X_I2C_SUPPORT