The tool used to generate the appropriate MACE MAVLINK definition files was a custom ported python script based on a development tool from the Ardupilot code base. The port was migrated to the MACE framework and is housed in the mavlink_cpp/MACE subdirectory of this code base.

The only prerequisites are that python is installed (see HERE for appropriate OS download and installation steps) and check that you can execute python scripts from the command line, within a shell, or as a executable file. Current checking has been done with Python 2.0.

Additionally, you need to install the pymavlink-mace package from this repository. It is located in (see HERE. This can be installed from the command line by navigating to the source directory and

python setup.py install

Once installation is complete, ensure that python can see the installed package.

Everything within the MAVLINK definitions is contained to individualized xml files governed by a schema. All subsequent definition files should be linked appropriately as contained at the top of the mace_common.xml file. An example is shown below modifying the original mace_common.xml and linking to an additional xml definition file called your_custom_defition_file.xml

<?xml version="1.0"?>
<mavlink>
  <include>common.xml</include>
  <include>mission.xml</include>
  <include>boundary.xml</include>
  <include>your_custom_defition_file.xml</include>

It is the responsibility of the developer to be diligent about code reuse and already existing definitions. If there are modifications necessary to any of the previous definitions, please update the appropriate definition rather than creating a new definition. As listed above, each included file in the definition is built in order. It should be recognized that there are a limited number of msg ID slots available per the MAVLINK definition. Each subsequent file added should allow room in this ID definition per the previous file before starting their ID definitions. Example being mission.xml contains definitions for messsage IDS 100->120. Leaving some room for potential follow on development, boundary.xmlbegins its definition at 130 and progresses. A developer should create a new xml file to encompass the communications they are trying to carry between MACE instances.

To define a custom enumeration, a developer may do so by simply performing the following in their XML file

To define a custom enumeration, a developer may do so by simply performing the following in their XML file

    <enum name="MAV_MISSION_TYPE">
      <description>Type of mission items being requested/sent in mission protocol.</description>
      <entry value="0" name="MAV_MISSION_TYPE_AUTO">
        <description>Items are mission commands for main auto mission.</description>
      </entry>
      ....
    </enum>

To define a custom message, a developer may do so by simply performing the following in their XML file

<message id="MSG_ID_NUM" name="MSG_NAME">
  <description>Custom description of the message</description>
  <field type="uint8_t" name="target_system">COMPONENT_DESCRIPTION</field>
</message>

Available Parameter Datatypes Include: Specifies the datatype of a MAVLink parameter.

1. 8,16,32,64 bit unsigned integers
2. 8,16,32,64 bit signed integers
3. 32,64 bit floating **It is important that the user minimize the parameter definition wherever possible to only encapsulate the expected data to be sent. This enables the transmission when serialized to have higher bandwidth and greater throughput from the modules **

mavgenerate.py is GUI code generator for MAVLink, written in Python.

Note Mavgenerate provides a GUI front end to the mavgen command line code generator, and supports the same options.

The GUI can be launched from anywhere using Python's -m argument:

python -m mavgenerate

Generator Steps:

1. Choose the target XML file (typically in mace_mavlink_generator/mavlink/mace_definitions).

   Note If using a custom dialect, first copy it into the above directory (if the dialect is dependent on common.xml it must be located in the same directory).

2. Choose an output directory (e.g. mavlink/include).

3. Select the target output programming language.

4. Select the target MAVLink protocol version (ideally 2.0)

   Caution Generation will fail if the protocol is not supported by the selected programming language.

5. Optionally check Validate and/or Validate Units (if checked validates XML specifications).

6. Click Generate to create the source files.

mavgen.py is a command-line tool for generating MAVLink libraries for different programming languages. After the mavlink directory has been added to the PYTHONPATH, it can be run by executing from the command line.

Tip This is the backend used by mavgenerate. The documentation below explains all the options for both tools.

For example, to generate MAVLink 2 C libraries for a dialect named your_custom_dialect.xml.

python -m pymavlink.tools.mavgen --lang=C --wire-protocol=2.0 --output=generated/include/mavlink/v2.0 message_definitions/v1.0/your_custom_dialect.xml

Note The syntax for for generating Python modules is the same, except that the --output specifies a filename rather than a directory.

The full syntax and options can be output by running mavgen with the -h flag (reproduced below):

usage: mavgen.py [-h] [-o OUTPUT]
                 [--lang {C,CS,JavaScript,Python,WLua,ObjC,Swift,Java,C++11}]
                 [--wire-protocol {0.9,1.0,2.0}] [--no-validate]
                 [--error-limit ERROR_LIMIT] [--strict-units]
                 XML [XML ...]

This tool generate implementations from MAVLink message definitions

positional arguments:
  XML                   MAVLink definitions

optional arguments:
  -h, --help            show this help message and exit
  -o OUTPUT, --output OUTPUT
                        output directory.
  --lang {C,CS,JavaScript,Python,WLua,ObjC,Swift,Java,C++11}
                        language of generated code [default: Python]
  --wire-protocol {0.9,1.0,2.0}
                        MAVLink protocol version. [default: 1.0]
  --no-validate         Do not perform XML validation. Can speed up code
                        generation if XML files are known to be correct.
  --error-limit ERROR_LIMIT
                        maximum number of validation errors to display
  --strict-units        Perform validation of units attributes.