max6675.cpp

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#include "max6675.h"
#include "esphome/core/log.h"
 
namespace esphome {
namespace max6675 {
 
static const char *const TAG = "max6675";
 
void MAX6675Sensor::update() {
  this->enable();
  delay(1);
  // conversion initiated by rising edge
  this->disable();
 
  // Conversion time typ: 170ms, max: 220ms
  auto f = std::bind(&MAX6675Sensor::read_data_, this);
  this->set_timeout("value", 250, f);
}
 
void MAX6675Sensor::setup() { this->spi_setup(); }
void MAX6675Sensor::dump_config() {
  LOG_SENSOR("", "MAX6675", this);
  LOG_PIN("  CS Pin: ", this->cs_);
  LOG_UPDATE_INTERVAL(this);
}
void MAX6675Sensor::read_data_() {
  this->enable();
  delay(1);
  uint8_t data[2];
  this->read_array(data, 2);
  uint16_t val = data[1] | (uint16_t(data[0]) << 8);
  this->disable();
 
  if ((val & 0x04) != 0) {
    // Thermocouple open
    ESP_LOGW(TAG, "Got invalid value from MAX6675Sensor (0x%04X)", val);
    this->status_set_warning();
    return;
  }
 
  float temperature = float(val >> 3) / 4.0f;
  ESP_LOGD(TAG, "'%s': Got temperature=%.1f°C", this->name_.c_str(), temperature);
  this->publish_state(temperature);
  this->status_clear_warning();
}
 
}  // namespace max6675
}  // namespace esphome