proto_sizes.h File Reference

Fundamental IO-Homecontrol frame and crypto size constants. More...

#include <cstdint>

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Namespaces
namespace	esphome
namespace	esphome::home_io_control

Variables
static constexpr uint8_t	esphome::home_io_control::NODE_ID_SIZE = 3
	Device/node addresses are 3 bytes (e.g., "123ABC").
static constexpr uint8_t	esphome::home_io_control::NODE_ID_STRING_SIZE = (NODE_ID_SIZE * 2) + 1
	Uppercase hex node ID plus null terminator.
static constexpr uint8_t	esphome::home_io_control::HMAC_SIZE = 6
	Authentication HMAC is 6 bytes (truncated AES output).
static constexpr uint8_t	esphome::home_io_control::AES_KEY_SIZE = 16
	AES-128 key size.
static constexpr uint8_t	esphome::home_io_control::AES_BLOCK_SIZE = 16
	AES block size.
static constexpr uint8_t	esphome::home_io_control::IV_SIZE = 16
	Initialization vector size for AES.
static constexpr uint8_t	esphome::home_io_control::IV_PADDING = 0x55
	Padding byte used in IV construction.
static constexpr uint8_t	esphome::home_io_control::BITS_PER_BYTE = 8
	Number of bits in one protocol byte.
static constexpr uint8_t	esphome::home_io_control::FRAME_MIN_SIZE = 9
	Minimum frame: CTRL0+CTRL1+DST(3)+SRC(3)+CMD(1).
static constexpr uint8_t	esphome::home_io_control::FRAME_MAX_SIZE = 32
	Maximum frame size (9 header + 23 data).
static constexpr uint8_t	esphome::home_io_control::FRAME_MAX_DATA_SIZE = 23
	Maximum data bytes after command ID.
static constexpr uint8_t	esphome::home_io_control::FRAME_CMD_OFFSET = 8
	Byte offset of the command ID in a raw wire buffer.
static constexpr uint8_t	esphome::home_io_control::FRAME_CRC_SIZE = 2
	CRC-CCITT trailer appended after the frame body.

Detailed Description

Fundamental IO-Homecontrol frame and crypto size constants.

These sizes are the lowest layer of the protocol model: node-ID widths, AES/HMAC sizes and frame bounds. They live in their own header so the other protocol headers can depend on them without pulling in the full frame API.

Definition in file proto_sizes.h.