vallox-rs485-protocol

The wire protocol of Vallox ventilation units that speak RS485, as a package of its own. It builds and reads the six-byte telegrams, converts the NTC temperature table, encodes fan levels and validates setpoints. It opens no serial port and imports no Home Assistant, so it can be read, audited and tested without either.

from vallox_rs485_protocol import create_read_request, ValloxTelegram, REG_FAN_SPEED

request = create_read_request(REG_FAN_SPEED)
request.to_bytes()  # b'\x01\x22\x11\x00\x29\x5d'

reply = ValloxTelegram.from_bytes(b"\x01\x11\x22\x29\x0f\x6b")
reply.register, reply.value

A telegram is SYSTEM, SENDER, RECIPIENT, VARIABLE, DATA, CHECKSUM. A read request carries VARIABLE = 0x00 and puts the register it asks about in DATA — the reply comes back with the register in VARIABLE.

How each register and each byte offset was established is recorded in docs/PROTOCOL.md of the integration repository. Change one, change the other.

Installation

pip install vallox-rs485-protocol

The Home Assistant integration pins this package with ==, and release-please raises the pin and the version here in one commit.

License

MIT