pya2ldb

Readme

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pyA2L is an ASAM MCD-2MC <https://www.asam.net/standards/detail/mcd-2-mc/>__ processing library written in Python.

If you work with ECUs, ASAP2/A2L is the contract that describes what and how to measure or calibrate. pyA2L helps you parse once, inspect and validate programmatically, automate checks, and export back when needed — all from Python.

Contents

• About ASAM MCD-2 MC (ASAP2)
• What pyA2L offers
• Installation
• Getting Started (Quickstart)
• Command-line usage
• Tips
• Examples
• Compatibility
• Project links
• Contributing
• Code of Conduct
• License
• Changelog / Release notes
• Acknowledgements

About ASAM MCD-2 MC (ASAP2)

ASAM MCD-2 MC (ASAP2) is the ASAM standard that defines the A2L description format for ECU measurement signals and calibration parameters. In practice, the A2L acts as a contract between ECU software and tools so different vendors can consistently locate data in memory and convert raw values into physical engineering units. Runtime transport (e.g., CCP/XCP) is out of scope of the standard.

For an authoritative overview of the standard, see the ASAM page: https://www.asam.net/standards/detail/mcd-2-mc/

What pyA2L offers

• Parse .a2l files and persist them as compact, queryable SQLite databases (.a2ldb) to avoid repeated parse costs.
• Programmatic access to ASAP2 entities via SQLAlchemy ORM models (MODULE, MEASUREMENT, CHARACTERISTIC, AXIS_DESCR, RECORD_LAYOUT, COMPU_METHOD/COMPU_TAB, UNIT, FUNCTION, GROUP, VARIANT_CODING, etc.).
• Rich inspection helpers in pya2l.api.inspect (e.g., Characteristic, Measurement, AxisDescr, ModPar, ModCommon) to compute shapes, axis info, allocated memory, conversions, and more.
• Validation utilities (pya2l.api.validate) to check common ASAP2 rules and project-specific consistency.
• Export .a2ldb content back to A2L text when needed.
• Building blocks for automation: reporting, quality gates, CI checks, and integration with CCP/XCP workflows.

Supported ASAP2 version: 1.6.

Why pyA2L?

• Parse once, query fast: Avoid repeated parser runs by working from SQLite.
• Powerful model: Use SQLAlchemy ORM to navigate ASAP2 entities naturally.
• Beyond parsing: Inspect derived properties, validate consistency, and export back to A2L.
• Automate: Integrate with CI to enforce quality gates on A2L content.

Design highlights

• SQLite-backed storage (.a2ldb) with SQLAlchemy models
• High-level inspection helpers in pya2l.api.inspect
• Validator framework in pya2l.api.validate yielding structured diagnostics
• Optional CLI for import/export tasks

Learn more about the standard at the ASAM website: https://www.asam.net/standards/detail/mcd-2-mc/wiki/

Installation

• Via pip: shell $ pip install pya2ldb IMPORTANT: Package-name is pya2ldb NOT pya2l!!!

• From Github:

  • Clone / fork / download pyA2Ldb repository <https://github.com/christoph2/pya2l>__.

Getting Started (Quickstart)

Parse once, work from SQLite thereafter.

Import a .a2l file and persist it as .a2ldb (SQLite):

.. code:: python

from pya2l import DB

db = DB() session = db.import_a2l( "ASAP2_Demo_V161.a2l", # Optional: # encoding="utf-8", # default is latin-1 # progress_bar=False, # silence the progress meter # loglevel="ERROR", # also suppresses progress )

Creates ASAP2_Demo_V161.a2ldb in the working directory

• Open an existing .a2ldb without re-parsing:

.. code:: python

from pya2l import DB

db = DB() session = db.open_existing("ASAP2_Demo_V161") # extension .a2ldb is implied

Query with SQLAlchemy ORM - List all measurements ordered by name with address and data type:

.. code:: python

from pya2l import DB import pya2l.model as model

db = DB() session = db.open_existing("ASAP2_Demo_V161") measurements = ( session.query(model.Measurement) .order_by(model.Measurement.name) .all() ) for m in measurements: print(f"{m.name:48} {m.datatype:12} 0x{m.ecu_address.address:08x}")

High-level inspection helpers - Use convenience wrappers from pya2l.api.inspect to access derived info:

.. code:: python

from pya2l import DB from pya2l.api.inspect import Characteristic, Measurement, AxisDescr

db = DB() session = db.open_existing("ASAP2_Demo_V161") ch = Characteristic(session, "ASAM.C.MAP.UBYTE.IDENTICAL") print("shape:", ch.dim().shape) print("element size:", ch.fnc_element_size(), "bytes") print("num axes:", ch.num_axes())

me = Measurement(session, "ASAM.M.SCALAR.UBYTE.IDENTICAL") print("is virtual:", me.is_virtual())

axis = ch.axisDescription("X") print("axis info:", axis.axisDescription("X"))

Validate your database

.. code:: python

from pya2l import DB from pya2l.api.validate import Validator

db = DB() session = db.open_existing("ASAP2_Demo_V161") vd = Validator(session) for msg in vd(): # iterate diagnostics # msg has fields: type (Level), category (Category), diag_code (Diagnostics), text (str) print(msg.type.name, msg.category.name, msg.diag_code.name, "-", msg.text)

Export back to A2L (optional)

.. code:: python

from pya2l import export_a2l

export_a2l("ASAP2_Demo_V161", "exported.a2l")

Tips

• Default import encoding is latin-1; override encoding= if your file differs.
• Silence the progress meter via progress_bar=False or loglevel="ERROR".
• Python package name is pya2ldb (not pya2l).
• See howto <./howto.rst>__ for Excel export and other short recipes.

Examples

• See pya2l/examples for sample A2L files and scripts.
• The Sphinx docs contain a fuller tutorial and HOWTO guides.

Create API and coverage parity

pyA2L offers a Creator API in pya2l.api.create to programmatically build or augment A2L content. The project’s goal is coverage parity: everything you can query via pya2l.api.inspect is intended to be creatable via pya2l.api.create.

Example: creating common entities

.. code:: python

from pya2l import DB from pya2l.api.create import ModuleCreator from pya2l.api.inspect import Module

Open or create a database

session = DB().open_create("MyProject.a2l") # or .a2ldb

mc = ModuleCreator(session)

Create a module

mod = mc.create_module("DEMO", "Demo ECU module")

Units and conversions

temp_unit = mc.add_unit(mod, name="degC", long_identifier="Celsius", display="°C", type_str="TEMPERATURE") ct = mc.add_compu_tab(mod, name="TAB_NOINTP_DEMO", long_identifier="Demo Tab", conversion_type="TAB_NOINTP", pairs=[(0, 0.0), (100, 1.0)], default_numeric=0.0)

Frames and transformers

fr = mc.add_frame(mod, name="FRAME1", long_identifier="Demo frame", scaling_unit=1, rate=10, measurements=["ENGINE_SPEED"]) tr = mc.add_transformer(mod, name="TR1", version="1.0", dllname32="tr32.dll", dllname64="tr64.dll", timeout=1000, trigger="ON_CHANGE", reverse="NONE", in_objects=["ENGINE_SPEED"], out_objects=["SPEED_PHYS"])

Typedefs and instances

ts = mc.add_typedef_structure(mod, name="TSig", long_identifier="Signal", size=8) mc.add_structure_component(ts, name="raw", type_ref="UWORD", offset=0) inst = mc.add_instance(mod, name="S1", long_identifier="Inst of TSig", type_name="TSig", address=0x1000)

Verify with inspect helpers

mi = Module(session) print("#frames:", len(list(mi.frame.query()))) print("#compu tabs:", len(list(mi.compu_tab.query())))

See pya2l/examples/create_quickstart.py for a more complete example.

Command-line usage

A small CLI is provided as a console script named a2ldb-imex:

.. code:: bash

Show version

$ a2ldb-imex -V

Import an A2L (creates .a2ldb next to the input or in CWD with -L)

$ a2ldb-imex -i path/to/file.a2l

Import with explicit encoding and create DB in current directory

$ a2ldb-imex -i path/to/file.a2l -E latin-1 -L

Export an .a2ldb back to A2L text (stdout by default or -o file)

$ a2ldb-imex -e path/to/file.a2ldb -o exported.a2l

Compatibility

• Python: 3.10 – 3.14
• Platforms: Prebuilt wheels are published for selected platforms. From source, Windows/macOS are supported; Linux may require building native extensions.

Project links

• Source code: https://github.com/christoph2/pyA2L
• Issue tracker: https://github.com/christoph2/pyA2L/issues
• PyPI: https://pypi.org/project/pya2ldb/
• Documentation <index.rst>__

Contributing

Contributions are welcome! Please open an issue to discuss significant changes before submitting a PR. See the existing tests under pya2l/tests and examples under pya2l/examples to get started. Contributors should use pre-commit to run formatting and lint checks before committing; see https://pre-commit.com/ for installation and usage.

Code of Conduct

This project follows a Code of Conduct to foster an open and welcoming community. Please read and abide by it when interacting in issues, discussions, and pull requests.

See CODE_OF_CONDUCT <../CODE_OF_CONDUCT.md>__ for full details.

Changelog / Release notes

See GitHub Releases: https://github.com/christoph2/pyA2L/releases

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