Enum GroupPayload 

pub enum GroupPayload {
    None,
    Optimized(u8),
    Octets(Vec<u8>),
}

The transmitted form of a group telegram’s data.

The A_GroupValue services carry their data in one of two forms, and the form is part of the frame, not a property of the byte values: data of six bits or less rides inside the service octet itself (the optimized form), and anything wider follows the service octets. Preserving the form here keeps the choice with the caller that knows the datapoint’s declared width - this layer places and extracts the bits, and never guesses the form from a value.

Variants

None

No data: the read service.

Optimized(u8)

The optimized form: the data bits carried inside the service octet, low-aligned. At most six bits, so at most 0x3F.

Octets(Vec<u8>)

The general form: the data octets following the service octets, most significant octet first.

Implementations

impl GroupPayload

pub const MAX_OCTETS: usize = 253

The widest data-octet count a group telegram can carry.

The extended frame’s length field carries 0 to 254 - the value 255 is the standard’s reserved escape, never a length - and the count starts after the transport-control octet, so the service octet takes 1 count and the data may take the other 253 (KNX TP1 medium clause on the extended length field; the Data Link Layer general clause on octet_count states the same rule).

pub const MAX_OPTIMIZED: u8 = 0x3F

The widest value the optimized form can carry: six bits.

pub fn optimized(value: u8) -> Result<Self>

Builds the optimized form, refusing a value the 6-bit carrier cannot state.

The sanctioned build route for a value arriving from runtime data; the refusal is byte-identical to the telegram mint’s own, so a value this accepts is one a telegram accepts.

pub fn octets(data: impl Into<Vec<u8>>) -> Result<Self>

Builds the general form, refusing empty data - no group service carries an empty octet sequence - and data beyond GroupPayload::MAX_OCTETS.

The sanctioned build route for octets arriving from runtime data; both refusals are byte-identical to the telegram mint’s own, so a payload this accepts is one a telegram accepts.

Trait Implementations

impl Clone for GroupPayload

fn clone(&self) -> GroupPayload

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for GroupPayload

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for GroupPayload

impl PartialEq for GroupPayload

fn eq(&self, other: &GroupPayload) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for GroupPayload