Description: The device's firmware version, consisting of a major version, minor version, release stage, and revision number, packed into 4 octets. The first octet contains the major version encoded as two packed binary coded decimal (bcd) digits. The second octet contains the minor version encoded as two packed bcd digits. The third byte contains the release stage, consisting of two packed bcd digits, the first of which is always zero and the second of which is either D (development), A (alpha), B (beta), E (experimental), or F (final). The fourth byte contains the revision number encoded as two packed bcd digits.

Thus, the firmware version '1.2 final' would be encoded as the octet string 01 02 0F 00.