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Bit Operations

Bit-level read/write operations.

These functions allow manipulation of individual bits within device registers without affecting other bits in the same register.

Functions​

wb_i2c_master_bus_read_byte_bit​

Reads a single bit from a byte register.

esp_err_t wb_i2c_master_bus_read_byte_bit(i2c_master_dev_handle_t dev_handle, uint8_t mem_address, uint8_t bit_num, uint8_t *data)

Parameters:

  • dev_handle (i2c_master_dev_handle_t): Handle to the I2C master device
  • mem_address (uint8_t): Memory address to read from
  • bit_num (uint8_t): Bit number to read (0-7, where 0 is LSB)
  • data (uint8_t *): Pointer to store the bit value (0 or 1)

Returns:

ESP_OK if successful, error code otherwise

This function reads a byte and returns the value of the specified bit.

wb_i2c_master_bus_read_byte_bits​

Reads multiple bits from a byte register.

esp_err_t wb_i2c_master_bus_read_byte_bits(i2c_master_dev_handle_t dev_handle, uint8_t mem_address, uint8_t bit_start, uint8_t length, uint8_t *data)

Parameters:

  • dev_handle (i2c_master_dev_handle_t): Handle to the I2C device
  • mem_address (uint8_t): Memory address to read from
  • bit_start (uint8_t): Starting bit position (MSB of the range, 0-7)
  • length (uint8_t): Number of bits to read (1-8)
  • data (uint8_t *): Pointer to store the extracted bits

Returns:

ESP_OK if successful, error code otherwise

This function reads a byte and extracts a range of bits.

wb_i2c_master_bus_write_byte_bit​

Write a single bit to a byte register.

esp_err_t wb_i2c_master_bus_write_byte_bit(i2c_master_dev_handle_t dev_handle, uint8_t mem_address, uint8_t bit_num, uint8_t data)

Parameters:

  • dev_handle (i2c_master_dev_handle_t): Handle to the I2C master device
  • mem_address (uint8_t): Memory address to write to
  • bit_num (uint8_t): Bit position to write (0-7, where 0 is LSB)
  • data (uint8_t): Bit value to write (0 or 1)

Returns:

ESP_OK if successful, otherwise an error code

This function reads the current byte value, modifies the specified bit, and writes it back to the device.

wb_i2c_master_bus_write_byte_bits​

Write multiple bits to a byte register.

esp_err_t wb_i2c_master_bus_write_byte_bits(i2c_master_dev_handle_t dev_handle, uint8_t mem_address, uint8_t bit_start, uint8_t length, uint8_t data)

Parameters:

  • dev_handle (i2c_master_dev_handle_t): Handle to the I2C master device
  • mem_address (uint8_t): Memory address to write to
  • bit_start (uint8_t): Starting bit position (MSB of the range, 0-7)
  • length (uint8_t): Number of bits to write (1-8)
  • data (uint8_t): Bit values to write

Returns:

ESP_OK if successful, otherwise an error code

This function reads the current byte, modifies the specified bit range, and writes it back to the device.