pub const MESSAGE_ID_MAX: u32 = 2u32.pow;
pub const ATTR_MESSAGE_ID: &str = "message_id";
pub const ATTR_CRC_EXTRA: &str = "crc_extra";
pub const ATTR_EXTENSION: &str = "extension";
pub const ATTR_BITMASK: &str = "bitmask";
pub const ATTR_BASE_TYPE: &str = "base_type";
pub const ATTR_REPR_TYPE: &str = "repr_type";
pub const ATTR_REPR: &str = "repr";