MicroPython Serial Protocol Generator

Generate your message exchange protocol layer. Make your life easier and don't repeat yourself. Define your messages and have code generated.

Generator is useful in case of communication between Raspberry Pi Pico (sensor) plugged into USB port of PC (host). Generator properly handles corner cases such as keyboard interrupt character (0x03) and new line character (\n). In first case interrupt handling have to be disabled. In second case new line causes read interrupt, so reading operation have to be resumed.

Main motivation of creating the project reluctance to do repetitive activities (copy-paste of code fragments to implement new messages) and error-prone defining of data frames.

Raspberry Pi Pico example

In examples directory is simple use case of the generator. It consists of steering onboard LED and reading inner temperature sensor. More details here.

Example consists of following JSON config:

{
    "_description_": "Host side config",
    "device_a": {
        "class_name": "HostConnector",
        "class_template": "protocol_lookup_dict.py.tmpl",
        "enum_name": "HostMessage",
        "enum_template": "message.py.tmpl"
    },

    "_description_": "Sensor side config",
    "device_b": {
        "class_name": "SensorConnector",
        "class_template": "protocol_lookup_dict.py.tmpl",
        "enum_name": "SensorMessage",
        "enum_template": "message.py.tmpl"
    },

	"_description_": "Package name to place code into",
    "package_name": "picoserial",

    "_description_": "type of message identifier, allowed: str, int or hex",
    "message_id_type": "hex",

    "_description_": [
    	"definition of messages",
		"allowed field types: bool, byte, int16, bytearray, str",
        "allowed message direction:",
        "  <empty>   both directions",
        "  BOTH      both directions",
        "  TO_A      from MCU (RPi Pico) to Host (PC)",
        "  TO_B      from Host to MCU",
        "  DISABLED  skip item"
    ],
    "messages": [
        { "id": "SET_KBD_INTR_RQST",        "direction": "TO_B", "fields": [ {"id": "new_state", "type": "bool"} ] },
        { "id": "SET_INTERNAL_LED_RQST",    "direction": "TO_B", "fields": [ {"id": "new_state", "type": "bool"} ] },
        { "id": "INTERNAL_TEMP_RQST",       "direction": "TO_B", "fields": [] },
        { "id": "TEST_BYTES_RQST",          "direction": "TO_B", "fields": [ {"id": "data_bytes", "type": "bytearray"}, {"id": "transfer_num", "type": "int16"} ] },
        { "id": "TEST_TEXT_RQST",           "direction": "TO_B", "fields": [ {"id": "content", "type": "str"}, {"id": "transfer_num", "type": "int16"} ] },

        { "id": "UNKNOWN_REQUEST_RSPNS",    "direction": "TO_A", "fields": [ {"id": "message", "type": "byte"} ] },
        { "id": "INTERNAL_TEMP_RSPNS",      "direction": "TO_A", "fields": [ {"id": "temperature", "type": "int16"} ] },
        { "id": "TEST_BYTES_RSPNS",         "direction": "TO_A", "fields": [ {"id": "data_bytes", "type": "bytearray"} ] },
        { "id": "TEST_TEXT_RSPNS",          "direction": "TO_A", "fields": [ {"id": "content", "type": "str"} ] }
    ]
}

Generating protocol

To generate protocol codes do following steps:

define configuration .json file (example: examples/pico-simple/pico-protocol.json)
execute generator python3 -m mpyserialprotogen with config file passed as argument

Type python3 -m mpyserialprotogen --help for supported input arguemnts or open help page.

Installation

Installation of package can be done by:

to install package from downloaded ZIP file execute: pip3 install --user -I file:mpython-serial-protogen-master.zip#subdirectory=src
to install package directly from GitHub execute: pip3 install --user -I git+https://github.com/anetczuk/mpython-serial-protogen.git#subdirectory=src
uninstall: pip3 uninstall mpyserialprotogen

Installation For development:

src/install-deps.sh to install package dependencies only (requirements.txt)
src/install-package.sh to install package in standard way through pip (with dependencies)
src/install-package-dev.sh to install package in developer mode using pip (with dependencies)

MicroPython limitations

no support for enum classes
no support for abc module

References

License

BSD 3-Clause License

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.