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MF4_CREATE_READER

Create a file reader for the MF4 format. Read CAN data from an ASAM Measurement Data File v4 (.mf4) as specified by the ASAM MDF standard (see https://www.asam.net/standards/detail/mdf/). Params: file : File The file to write from. Returns: out : Stateful A stateful object that contains can a list of message.
Python Code
from flojoy import flojoy, File, Stateful, DataContainer
import can
from typing import Optional


@flojoy(deps={"python-can": "4.3.1", "asammdf": "7.4.1"})
def MF4_CREATE_READER(
    file: File,
    default: Optional[DataContainer] = None,
) -> Stateful:
    """Create a file reader for the MF4 format.

    Read CAN data from an ASAM Measurement Data File v4 (.mf4) as specified by the ASAM MDF standard (see https://www.asam.net/standards/detail/mdf/).

    Parameters
    ----------
    file : File
        The file to write from.

    Returns
    -------
    Stateful
        A stateful object that contains can a list of message.
    """

    reader = can.io.MF4Reader(file.unwrap())

    messages = []
    for message in reader:
        messages.append(message)

    return Stateful(messages)

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Example

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React Flow mini map

This application demonstrates how to use multiple CAN blocks to connect to a PEAK-USB device and read messages from it. The PEAK-USB device is a USB-to-CAN interface that enables you to connect a computer to a CAN network. This device is used in this case to capture the messages of a particular sensor by filtering them directly at the kernel level, thus reducing the load on the CPU, and save those messages to a log file locally.

Once the app is done, the generated logs are exported to an S3 bucket to keep a record of the sensor’s data for further analysis.

To replicate this application, you must connect the PEAK-USB to your computer and install the required driver (refer to the PEAK_CONNECT blocks for more information on the necessary driver for your platform). Then, simply specify the PEAK-USB channel in the required blocks, and this Flojoy application will log the messages received by the device!

Detecting channels A valuable block is the PEAK_DETECT_AVAILABLE_DEVICE. This block allows you to display the devices using the PCAN interface that are connected to your computer.