// MIT License // // Copyright (c) 2023-2024 Rob Tillaart // // Permission is hereby granted, free of charge, to any person obtaining a copy // of this software and associated documentation files (the "Software"), to deal // in the Software without restriction, including without limitation the rights // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell // copies of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be included in all // copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE // SOFTWARE. #include "am2315c.h" #include "esphome/core/hal.h" #include "esphome/core/helpers.h" #include "esphome/core/log.h" namespace esphome { namespace am2315c { static const char *const TAG = "am2315c"; uint8_t AM2315C::crc8_(uint8_t *data, uint8_t len) { uint8_t crc = 0xFF; while (len--) { crc ^= *data++; for (uint8_t i = 0; i < 8; i++) { if (crc & 0x80) { crc <<= 1; crc ^= 0x31; } else { crc <<= 1; } } } return crc; } bool AM2315C::reset_register_(uint8_t reg) { // code based on demo code sent by www.aosong.com // no further documentation. // 0x1B returned 18, 0, 4 // 0x1C returned 18, 65, 0 // 0x1E returned 18, 8, 0 // 18 seems to be status register // other values unknown. uint8_t data[3]; data[0] = reg; data[1] = 0; data[2] = 0; ESP_LOGD(TAG, "Reset register: 0x%02x", reg); if (this->write(data, 3) != i2c::ERROR_OK) { ESP_LOGE(TAG, "Write failed!"); this->mark_failed(); return false; } delay(5); if (this->read(data, 3) != i2c::ERROR_OK) { ESP_LOGE(TAG, "Read failed!"); this->mark_failed(); return false; } delay(10); data[0] = 0xB0 | reg; if (this->write(data, 3) != i2c::ERROR_OK) { ESP_LOGE(TAG, "Write failed!"); this->mark_failed(); return false; } delay(5); return true; } bool AM2315C::convert_(uint8_t *data, float &humidity, float &temperature) { uint32_t raw; raw = (data[1] << 12) | (data[2] << 4) | (data[3] >> 4); humidity = raw * 9.5367431640625e-5; raw = ((data[3] & 0x0F) << 16) | (data[4] << 8) | data[5]; temperature = raw * 1.9073486328125e-4 - 50; return this->crc8_(data, 6) == data[6]; } void AM2315C::setup() { ESP_LOGCONFIG(TAG, "Setting up AM2315C..."); // get status uint8_t status = 0; if (this->read(&status, 1) != i2c::ERROR_OK) { ESP_LOGE(TAG, "Read failed!"); this->mark_failed(); return; } // reset registers if required, according to the datasheet // this can be required after power on, although this was // never required during testing if ((status & 0x18) != 0x18) { ESP_LOGD(TAG, "Resetting AM2315C registers"); if (!this->reset_register_(0x1B)) { this->mark_failed(); return; } if (!this->reset_register_(0x1C)) { this->mark_failed(); return; } if (!this->reset_register_(0x1E)) { this->mark_failed(); return; } } } void AM2315C::update() { // request measurement uint8_t data[3]; data[0] = 0xAC; data[1] = 0x33; data[2] = 0x00; if (this->write(data, 3) != i2c::ERROR_OK) { ESP_LOGE(TAG, "Write failed!"); this->mark_failed(); return; } // wait for hw to complete measurement set_timeout(160, [this]() { // check status uint8_t status = 0; if (this->read(&status, 1) != i2c::ERROR_OK) { ESP_LOGE(TAG, "Read failed!"); this->mark_failed(); return; } if ((status & 0x80) == 0x80) { ESP_LOGE(TAG, "HW still busy!"); this->mark_failed(); return; } // read uint8_t data[7]; if (this->read(data, 7) != i2c::ERROR_OK) { ESP_LOGE(TAG, "Read failed!"); this->mark_failed(); return; } // check for all zeros bool zeros = true; for (uint8_t i : data) { zeros = zeros && (i == 0); } if (zeros) { ESP_LOGW(TAG, "Data all zeros!"); this->status_set_warning(); return; } // convert float temperature = 0.0; float humidity = 0.0; if (this->convert_(data, humidity, temperature)) { if (this->temperature_sensor_ != nullptr) { this->temperature_sensor_->publish_state(temperature); } if (this->humidity_sensor_ != nullptr) { this->humidity_sensor_->publish_state(humidity); } this->status_clear_warning(); } else { ESP_LOGW(TAG, "CRC failed!"); this->status_set_warning(); } }); } void AM2315C::dump_config() { ESP_LOGCONFIG(TAG, "AM2315C:"); LOG_I2C_DEVICE(this); if (this->is_failed()) { ESP_LOGE(TAG, "Communication with AM2315C failed!"); } LOG_SENSOR(" ", "Temperature", this->temperature_sensor_); LOG_SENSOR(" ", "Humidity", this->humidity_sensor_); } float AM2315C::get_setup_priority() const { return setup_priority::DATA; } } // namespace am2315c } // namespace esphome