Crate aprs 

APRS (Automatic Packet Reporting System) protocol stack.

This crate provides a std-only, sans-io implementation of the APRS protocol over AX.25, including the core stateful algorithms used by real APRS clients: digipeater path handling, SmartBeaconing, messaging ack/rej tracking, and heard-station lists.

Scope

• APRS 1.0.1 / 1.2 info-field parsing: position (compressed and uncompressed), Mic-E, messages, status, weather, telemetry, items, objects, queries.
• Builders for constructing outgoing info fields.
• Stateful algorithms: DigipeaterConfig (with 30s dup cache and viscous delay), SmartBeaconing (HamHUD formula), AprsMessenger (ack/rej + retry), StationList (heard-station DB with expiry).

Time handling

This crate is sans-io and never calls std::time::Instant::now(). Every stateful method accepts a now: Instant parameter; callers in the tokio shell layer (e.g. kenwood-thd75::aprs::AprsClient) read the wall clock once per iteration and thread it down.

References

• APRS 1.0.1: http://www.aprs.org/doc/APRS101.PDF
• APRS 1.2: http://www.aprs.org/aprs12.html

Structs

AprsDataExtension

Parsed APRS data extensions from the position comment field.

AprsItem

An APRS item report (data type ) ).

AprsMessage

An APRS message (data type :) addressed to a specific station or group.

AprsMessenger

Manages APRS message send/receive with automatic ack/retry.

AprsObject

An APRS object report (data type ;).

AprsPacket

A parsed APRS packet. Currently just a thin wrapper over AprsData; future extensions may add envelope-level fields (source callsign, digipeater path) if the APRS layer ever owns the AX.25 context.

AprsPosition

A parsed APRS position report.

AprsStatus

An APRS status report (data type >).

AprsSymbol

A full APRS symbol (table selector + 1-byte code).

AprsTelemetry

Parsed APRS telemetry report.

AprsWeather

An APRS weather report.

Course

A course-over-ground value, validated to 0..=360 degrees.

DigipeaterAlias

A typed digipeater alias.

DigipeaterConfig

Digipeater configuration.

Fahrenheit

Temperature in degrees Fahrenheit as used by APRS weather reports.

Latitude

Geographic latitude in decimal degrees, validated to [-90.0, 90.0].

Longitude

Geographic longitude in decimal degrees, validated to [-180.0, 180.0].

MessageId

An APRS message identifier: 1 to 5 alphanumeric characters.

MessengerConfig

Configuration knobs for the APRS messenger.

ParseContext

Diagnostic context for a parse failure.

Phg

Power-Height-Gain-Directivity data (APRS101 Chapter 7).

SmartBeaconing

SmartBeaconing algorithm for adaptive APRS position beacon timing.

SmartBeaconingConfig

Configuration for the SmartBeaconing algorithm.

StationEntry

A single station’s latest state.

StationList

Tracks APRS stations heard on the network.

TelemetryParameters

5 analog + 8 digital channel labels used by both PARM. and UNIT..

Tocall

An APRS “tocall” — the destination callsign used to identify the originating software or device.

Enums

AprsData

A parsed APRS data frame, covering all major APRS data types.

AprsError

Errors produced by APRS parsing, building, and stateful algorithms.

AprsQuery

Parsed APRS query.

AprsTimestamp

An APRS timestamp as used by object and position-with-timestamp reports (APRS 1.0.1 §6.1).

BeaconReason

Reason a SmartBeacon was triggered at a given moment.

BeaconState

SmartBeaconing runtime state.

DigiAction

Result of digipeater processing.

MessageKind

APRS message kind (per APRS 1.0.1 §14 and bulletin sections).

MiceMessage

Mic-E standard message code.

PositionAmbiguity

APRS position ambiguity level (APRS 1.0.1 §8.1.6).

Speed

A ground-speed measurement with explicit units.

SymbolTable

An APRS symbol table selector.

TelemetryDefinition

Telemetry parameter definitions sent as APRS messages.

Constants

DEFAULT_DEDUP_TTL

Default rolling dedup window for digipeater retransmission suppression.

DEFAULT_VISCOUS_DELAY

Default viscous delay for fill-in digipeaters.

INCOMING_DEDUP_WINDOW

How long an incoming message’s (source, msgno) stays in the dedup cache before being purged.

MAX_APRS_MESSAGE_TEXT_LEN

Maximum APRS message text length in bytes (APRS 1.0.1 §14).

MAX_RETRIES

Maximum number of transmission attempts per message before giving up (the default used when MessengerConfig::default is in play).

RETRY_INTERVAL

Default interval between retry attempts.

Functions

build_aprs_item

Build a KISS-encoded APRS item report.

build_aprs_item_packet

Like build_aprs_item but returns the unencoded [Ax25Packet].

build_aprs_message

Build a KISS-encoded APRS message packet.

build_aprs_message_checked

Like build_aprs_message but returns an error when the text exceeds the APRS 1.0.1 67-byte limit instead of silently truncating.

build_aprs_message_packet

Like build_aprs_message but returns the unencoded [Ax25Packet].

build_aprs_mice

Build a Mic-E encoded APRS position report for KISS transmission.

build_aprs_mice_with_message

Build a Mic-E encoded APRS position report with a specific MiceMessage status code.

build_aprs_mice_with_message_packet

Like build_aprs_mice_with_message but returns the unencoded [Ax25Packet] for callers that want to inspect or route it.

build_aprs_object

Build a KISS-encoded APRS object report.

build_aprs_object_with_timestamp

Build a KISS-encoded APRS object report with a caller-supplied timestamp.

build_aprs_object_with_timestamp_packet

Like build_aprs_object_with_timestamp but returns the unencoded [Ax25Packet] for callers that want to inspect or route it.

build_aprs_position_compressed

Build a KISS-encoded APRS compressed position report.

build_aprs_position_compressed_packet

Like build_aprs_position_compressed but returns the unencoded [Ax25Packet].

build_aprs_position_report

Build a KISS-encoded APRS uncompressed position report.

build_aprs_position_report_packet

Like build_aprs_position_report but returns the unencoded [Ax25Packet] so callers can inspect, log, or route it before wrapping it in KISS framing.

build_aprs_position_weather

Build a combined APRS position + weather report as a single KISS frame, per APRS 1.0.1 §12.1.

build_aprs_position_weather_packet

Like build_aprs_position_weather but returns the unencoded [Ax25Packet].

build_aprs_status

Build a KISS-encoded APRS status report.

build_aprs_status_packet

Like build_aprs_status but returns the unencoded [Ax25Packet].

build_aprs_weather

Build a KISS-encoded positionless APRS weather report.

build_aprs_weather_packet

Like build_aprs_weather but returns the unencoded [Ax25Packet].

build_query_response_position

Build a position query response as a KISS-encoded APRS position report.

classify_ack_rej

Classify a message text as an APRS ack or rej control frame.

decode_base91_4

Decode a 4-byte base-91 value.

extract_position_weather

Try to extract weather data embedded in a position report’s comment.

mice_message_bits

Map a Mic-E standard message code to its 3-bit (A, B, C) encoding.

parse_aprs_data

Parse any APRS data frame from an AX.25 information field.

parse_aprs_data_full

Parse any APRS data frame, including Mic-E types that require the AX.25 destination address.

parse_aprs_extensions

Parse data extensions from an APRS position comment string.

parse_aprs_item

Parse an APRS item report ()name!pos... or )name_pos...).

parse_aprs_message

Parse an APRS message (:ADDRESSEE:text{id).

parse_aprs_object

Parse an APRS object report (;name_____*DDHHMMzpos...).

parse_aprs_position

Parse an APRS position report from an AX.25 information field.

parse_aprs_query

Parse an APRS query (?APRSx or ?text).

parse_aprs_status

Parse an APRS status report (>text).

parse_aprs_telemetry

Parse an APRS telemetry report (T#seq,v1,v2,v3,v4,v5,dddddddd).

parse_aprs_weather_positionless

Parse a positionless APRS weather report (_MMDDHHMMdata).

parse_compressed_body

Parse compressed APRS position body (APRS101.PDF Chapter 9).

parse_mice_position

Parse a Mic-E encoded APRS position (APRS101.PDF Chapter 10).

parse_uncompressed_body

Parse uncompressed APRS position body.