Telemetry-Packet-Set-Specifiers.adoc

Telemetry Packet Set Specifiers

A telemetry packet set specifier arranges the telemetry channels of a topology into a set of telemetry packets. A telemetry packet set specifier is part of a topology definition.

Syntax

telemetry packets identifier { telemetry-packet-group-member-sequence } [ omit { telemetry-channel-identifier-sequence } ]

telemetry-packet-group-member-sequence is an element sequence in which each element is a telemetry packet group member, and the terminating punctuation is a comma. A telemetry packet group member is one of the following:

• An include specifier.

• A telemetry packet specifier.

telemetry-channel-identifier-sequence is an element sequence in which each element is a telemetry channel identifier, and the terminating punctuation is a comma.

Semantics

FPP recursively resolves any include specifiers in telemetry-packet-group-member-sequence. This action converts telemetry-packet-group-member-sequence to a list L of telemetry packet specifiers, each of which is a list of telemetry channel identifiers. FPP then checks the following:

1. Each telemetry packet specifier in L is valid,

2. Each telemetry packet specifier in L has a distinct name and a distinct identifier.

3. For every component instance I available in the enclosing topology, either through direct specification or through import, for every telemetry channel T that is a member of I, exactly one of the following is true:

   1. T appears in at least one of the telemetry packet specifiers of L.

   2. telemetry-channel-identifier-sequence is present, and T appears in telemetry-channel-identifier-sequence.

Example

telemetry packets Packets {

  packet CDH id 0 group 0 {
    commandDispatcher.commandsDispatched
    rateGroup1Hz.rgMaxTime
    fileUplink.filesReceived
  }

  packet ADCS id 1 group 2 {
    adcs.mode
    adcs.attitude
  }

  include "PowerTelemetryPackets.fppi"

} omit {
  adcs.extraTelemetry
}