sht3xd.cpp

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#include "sht3xd.h"
#include "esphome/core/log.h"
 
namespace esphome {
namespace sht3xd {
 
static const char *const TAG = "sht3xd";
 
// https://sensirion.com/media/documents/E5762713/63D103C2/Sensirion_electronic_identification_code_SHT3x.pdf
// indicates two possible read serial number registers either with clock stretching enabled or disabled.
// Other SHT3XD_COMMAND registers use the clock stretching disabled register.
// To ensure compatibility, reading serial number using the register with clock stretching register enabled
// (used originally in this component) is tried first and if that fails the alternate register address
// with clock stretching disabled is read.
// If both fail (e.g. some clones don't support the command), we continue so temp/humidity still work.
// Second attempt uses 10ms delay for boards that need more time before read (max permitted by ESPHome guidelines).
 
static const uint16_t SHT3XD_COMMAND_READ_SERIAL_NUMBER_CLOCK_STRETCHING = 0x3780;
static const uint16_t SHT3XD_COMMAND_READ_SERIAL_NUMBER = 0x3682;
 
static const uint16_t SHT3XD_COMMAND_READ_STATUS = 0xF32D;
static const uint16_t SHT3XD_COMMAND_CLEAR_STATUS = 0x3041;
static const uint16_t SHT3XD_COMMAND_HEATER_ENABLE = 0x306D;
static const uint16_t SHT3XD_COMMAND_HEATER_DISABLE = 0x3066;
static const uint16_t SHT3XD_COMMAND_SOFT_RESET = 0x30A2;
static const uint16_t SHT3XD_COMMAND_POLLING_H = 0x2400;
static const uint16_t SHT3XD_COMMAND_FETCH_DATA = 0xE000;
 
void SHT3XDComponent::setup() {
  uint16_t raw_serial_number[2]{0};
  if (!this->get_register(SHT3XD_COMMAND_READ_SERIAL_NUMBER_CLOCK_STRETCHING, raw_serial_number, 2)) {
    if (!this->get_register(SHT3XD_COMMAND_READ_SERIAL_NUMBER, raw_serial_number, 2, 10)) {
      ESP_LOGW(TAG, "Serial number read failed, continuing without it (clone or non-standard sensor)");
    }
  }
  this->serial_number_ = (uint32_t(raw_serial_number[0]) << 16) | uint32_t(raw_serial_number[1]);
 
  if (!this->write_command(this->heater_enabled_ ? SHT3XD_COMMAND_HEATER_ENABLE : SHT3XD_COMMAND_HEATER_DISABLE)) {
    this->mark_failed(LOG_STR("Failed to set heater mode"));
    return;
  }
}
 
void SHT3XDComponent::dump_config() {
  ESP_LOGCONFIG(TAG,
                "SHT3xD:\n"
                "  Serial Number: 0x%08" PRIX32 "\n"
                "  Heater Enabled: %s",
                this->serial_number_, TRUEFALSE(this->heater_enabled_));
  LOG_I2C_DEVICE(this);
  LOG_UPDATE_INTERVAL(this);
  LOG_SENSOR("  ", "Temperature", this->temperature_sensor_);
  LOG_SENSOR("  ", "Humidity", this->humidity_sensor_);
}
 
void SHT3XDComponent::update() {
  if (this->status_has_warning()) {
    ESP_LOGD(TAG, "Retrying to reconnect the sensor.");
    this->write_command(SHT3XD_COMMAND_SOFT_RESET);
  }
  if (!this->write_command(SHT3XD_COMMAND_POLLING_H)) {
    this->status_set_warning();
    return;
  }
 
  this->set_timeout(50, [this]() {
    uint16_t raw_data[2];
    if (!this->read_data(raw_data, 2)) {
      this->status_set_warning();
      return;
    }
 
    float temperature = 175.0f * float(raw_data[0]) / 65535.0f - 45.0f;
    float humidity = 100.0f * float(raw_data[1]) / 65535.0f;
 
    ESP_LOGD(TAG, "Got temperature=%.2f°C humidity=%.2f%%", temperature, humidity);
    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();
  });
}
 
}  // namespace sht3xd
}  // namespace esphome