i2c_sensirion.h

Go to the documentation of this file.

#pragma once
#include "esphome/components/i2c/i2c.h"
#include "esphome/core/helpers.h"
 
#include <vector>
 
namespace esphome::sensirion_common {
 
static const uint8_t CRC_POLYNOMIAL = 0x31;  // default for Sensirion
 
static constexpr uint8_t SENSIRION_OPTION_READ_MAY_NACK = 1u << 0;
 
class SensirionI2CDevice : public i2c::I2CDevice {
 public:
  enum CommandLen : uint8_t { ADDR_8_BIT = 1, ADDR_16_BIT = 2 };
 
  static inline const char *sensirion_convert_to_string_in_place(uint16_t *array, size_t length) {
    for (size_t i = 0; i < length; i++) {
      array[i] = convert_big_endian(array[i]);
    }
    return reinterpret_cast<const char *>(array);
  }
 
  bool read_data(uint16_t *data, uint8_t len);
 
  bool read_data(uint16_t &data) { return this->read_data(&data, 1); }
 
  bool get_register(uint16_t command, uint16_t *data, uint8_t len, uint8_t delay = 0) {
    return get_register_(command, ADDR_16_BIT, data, len, delay);
  }
  bool get_register(uint16_t i2c_register, uint16_t &data, uint8_t delay = 0) {
    return this->get_register_(i2c_register, ADDR_16_BIT, &data, 1, delay);
  }
 
  bool get_8bit_register(uint8_t i2c_register, uint16_t *data, uint8_t len, uint8_t delay = 0) {
    return get_register_(i2c_register, ADDR_8_BIT, data, len, delay);
  }
 
  bool get_8bit_register(uint8_t i2c_register, uint16_t &data, uint8_t delay = 0) {
    return this->get_register_(i2c_register, ADDR_8_BIT, &data, 1, delay);
  }
 
  template<class T> bool write_command(T i2c_register) { return write_command(i2c_register, nullptr, 0); }
 
  template<class T> bool write_command(T i2c_register, uint16_t data) { return write_command(i2c_register, &data, 1); }
 
  template<class T> bool write_command(T i2c_register, const std::vector<uint16_t> &data) {
    return write_command_(i2c_register, sizeof(T), data.data(), data.size());
  }
 
  template<class T> bool write_command(T i2c_register, const uint16_t *data, uint8_t len) {
    // limit to 8 or 16 bit only
    static_assert(sizeof(i2c_register) == 1 || sizeof(i2c_register) == 2, "Only 8 or 16 bit command types supported");
    return write_command_(i2c_register, CommandLen(sizeof(T)), data, len);
  }
 
 protected:
  bool write_command_(uint16_t command, CommandLen command_len, const uint16_t *data, uint8_t data_len);
 
  bool get_register_(uint16_t reg, CommandLen command_len, uint16_t *data, uint8_t len, uint8_t delay,
                     uint8_t sensirion_options = 0);
 
  i2c::ErrorCode last_error_;
};
 
}  // namespace esphome::sensirion_common