pyarinc429

pyarinc429 is a separate ARINC 429 library derived from the original implementation by Jason Hodge.
It expands the original project with additional ARINC 429 utilities, ICD metadata handling, ICD‑driven code generation, ARINC 615 framing, Williamsburg block‑transfer, and a full ARINC 429 simulation engine.

Original repository:
https://github.com/aeroneous/PyARINC429

---

Installation

git clone https://github.com/JaskRendix/pyarinc429
cd pyarinc429
pip install .

Run tests:

pip install .[test]
pytest

---

Package layout

arinc429/
    word.py
    bitfields.py
    decoding.py
    errors.py
    builder.py
    definitions.py
    labelinfo.py
    labels.py
    datatypes/
        base.py
        bcd.py
        bnr.py
        discrete.py
    loader.py
    williamsburg.py
    icd.py
    sim.py
    drivers.py
    cli.py
examples/
    README.md
    flight_sim.py
    multi_fault_sim.py
    high_rate_stress_test.py
    datatypes_integration.py
    record_and_replay.py

---

Word

Word represents a 32‑bit ARINC 429 word with full bit‑field access and parity handling.

Fields:

• label
• sdi
• data
• ssm
• parity
• parity_type
• parity_ok
• raw

Methods:

• get_bit_field(lsb, msb)
• set_bit_field(lsb, msb, value)
• from_int(value, parity_type)
• to_int()
• copy()
• with_fields(...)
• as_dict()
• to_json()
• validate()

---

WordBuilder

Fluent builder for constructing valid ARINC 429 words.

from arinc429.builder import WordBuilder

w = (
    WordBuilder()
    .label(0o123)
    .sdi(1)
    .data(0x55AA)
    .ssm(2)
    .parity_type(Word.EVEN_PARITY)
    .strict_parity(True)
    .build()
)

---

Datatypes

Typed helpers for decoding ARINC 429 numeric formats:

• BCD
• BNR
• Discrete

Each datatype supports:

• encoded / decoded values
• resolution
• numeric conversion
• JSON serialization

---

Label metadata

Metadata for ARINC 429 labels:

LabelInfo(label, name, system, category, direction=None, description=None)
LABEL_INFO
get_label_info()
require_label_info()

---

Definitions

Structures for ICD‑driven decoding:

FieldDefinition(name, lsb, msb, type, resolution=None, unit=None)
LabelDefinition(name, fields, info=None)

Equipment sets:

• EQUIP_ADC
• EQUIP_IRS
• EQUIP_ALL

Combine sets:

from arinc429.api import combine_definitions
custom = combine_definitions(EQUIP_ADC, EQUIP_IRS)

---

ARINC 615 packetizer

from arinc429.loader import Arinc615Packetizer

p = Arinc615Packetizer(b"HELLO")
words = p.to_words()
decoded = Arinc615Packetizer.decode(words)

---

Williamsburg protocol engine

Implements the ARINC 429 Williamsburg block‑transfer state machine with CRC‑16‑CCITT, padding, and control‑word sequencing.

---

ICD loader

from arinc429.icd import load_icd_json
labels = load_icd_json("icd.json")

---

ICD code generator

Generate Python dataclasses and decoders from an ICD JSON file:

pyarinc generate icd.json
pyarinc generate icd.json --output custom_icd.py

The generated module contains:

• one dataclass per label
• a from_word() decoder for each dataclass
• an ICD_REGISTRY mapping label → dataclass
• a decode_icd_word() helper

BNR fields are sign‑extended from their defined width.
BCD fields derive their sign from SSM bits.

---

Simulation engine (arinc429.sim)

Provides a virtual ARINC 429 databus.

Components:

• ArincBus
• VirtualNode
• BusMonitor
• FaultConfig
• FaultyVirtualNode
• BusRecorder
• ReplayNode
• stop_all()

Example:

from arinc429.sim import ArincBus, VirtualNode, BusMonitor, BusRecorder, ReplayNode, stop_all
from arinc429.builder import WordBuilder
import time
from pathlib import Path

bus = ArincBus()
monitor = BusMonitor("MON", bus)

adc = VirtualNode("ADC", bus)
adc.register_periodic_transmission(
    lambda: WordBuilder().label(0o203).data(0x1234).build(),
    rate_hz=20.0,
)
adc.start()

time.sleep(1.0)
stop_all([adc])

log_file = Path("record.jsonl")
BusRecorder.export_to_jsonl(monitor.captured_words, log_file)

replay_bus = ArincBus()
replay_monitor = BusMonitor("REPLAY_MON", replay_bus)
ReplayNode(log_file, replay_bus, speed_multiplier=2.0).play()

---

Hardware drivers (arinc429.drivers)

Transport layer:

• ArincTransport
• SerialTransport
• SocketTransport

Driver layer:

• BaseArincDriver
• AsyncBusTransportDriver

Drivers bridge physical ARINC 429 hardware (serial adapters, UDP/TCP gateways) with the virtual bus.

---

CLI (pyarinc)

Command‑line interface for decoding, packetizing, Williamsburg simulation, ICD loading, ICD code generation, and bus simulation.

Decode a raw word

pyarinc decode 0x9c000c26
pyarinc decode 0x9c000c26 --json
pyarinc decode 0x9c000c26 --profile adc --parity even

ARINC 615 packetization

pyarinc arinc615-encode "HELLO"
pyarinc arinc615-encode --file payload.bin

Williamsburg simulation

pyarinc williamsburg-simulate "HELLO"

Load ICD metadata

pyarinc load-icd icd.json

Generate ICD module

pyarinc generate icd.json
pyarinc generate icd.json --output custom_icd.py

Bus simulation

pyarinc simulate --duration 2.0
pyarinc simulate --duration 2.0 --faulty

Replay recorded traffic

pyarinc replay flight_recording.jsonl --speed 1.0

---

Examples

See:

examples/README.md

for descriptions of:

• flight_sim.py
• multi_fault_sim.py
• high_rate_stress_test.py
• datatypes_integration.py
• record_and_replay.py