Since 2020 I have been using MicroPython on a number of embedded devices. My journey with MicroPython started with PyCom devices in 2020. The PyCom device I worked with was the FiPy. The was built around the Espressif 32-bit dual core LX6 processor, with 4 MB of memory and 8 MB of FLASH. It had many other features, notably LoRa, Sigfox, WiFi, Bluetooth Low Energy (BLE), and cellular LTE–CAT M1/NB1.
Pycom shipped the FiPy with their forked version of MicroPython 1.11. They added drivers for LoRa, Sigfox, and LTE, as well as MicroPython support for those devices.
Using the FiPy and the PyTracker, I created a LoRa-based mesh networked portable system written in MicroPython. The system was meant to track the position of people and vehicles, and to relay that information back to a central computer that then displayed all those positions on a map in near-real-time.
Unfortunately the money that initially provided impetus for this project wasn't renewed, and it eventually landed in my lap. If you're curious about the software, it's in the folder TeamTrack2.
I wasn't particularly happy with Pycom's version of MicroPython. My biggest issue with Pycom's version was how it would randomly core dump, causing the device to restart. I tried to determine the cause and a fix, but support was not very good.
In 2021 I began to notice that Espressif was releasing development boards using the ESP32-S3. The ESP32-S3 had WiFi and BLE, and was based on the LX7 core. The boards were sold with various mixes of RAM and FLASH amounts; I eventually settled on N8R8 (8 MB FLASH, 8 MB RAM) and N32R8 (32 MB of FLASH, 8 MB of RAM). I also downloaded and installed Espressif's ESP-IDF framework and started to program the boards in C and C++. It was with release 4.x that I started using the ESP-IDF.
I also forked the MicroPython source repo. It was from my fork that I would clone down to my development system (Linx Mint) and build my own MicroPython firmware, which I then flashed onto the boards. I did this primarily to create a firewall between developers checking into the MicroPython project and work I was doing at the time. One of the side benefits of having my own copy is that I could see all the changes that occured on the main project branch before syncing my copy, and then syncing my github copy with my system copy.
I also had the benefit of having firmware with up-to-date fixes and being built with Espressif's latest tools. It concerned me that the MicroPython project had fallen behind its using up-to-date Espressif tooling.
The fundamental issue at the time was that MicroPython did not support a number of advanced Espressif boards. I had to configure my copy to support the type and amount of RAM and FLASH in order for MicroPython to work on the ESP32-S3 boards in my possession.
As of MicroPython 1.24.0, that is no longer an issue. You can download firmware from the MicroPython website and it will boot and run properly.
All of my devices use a naming nomencature that is synthesized from the board's system name and the last four digits of the board's unique ID. The following code works for regular MicroPython.
import binascii
import machine as ma
import os
UNAME = os.uname().sysname.upper()
UNIQUE_ID = binascii.hexlify(ma.unique_id()).decode('ascii').upper()
SSID = UNAME + '-' + UNIQUE_ID[-4:]I call the final result SSID because a number of the Espressif boards are programmed to act as stand-alone WiFi access points. Whether the SSID is used for that or not, it makes for a unique identifier for all the boards.
Because of the limited resources on the micro:bit devices, the following code is used to determine the naming nomenclature.
import machine as ma
import os
UNAME = os.uname().sysname.upper()
UNIQUE_ID = ''.join("{:02X}".format(b) for b in ma.unique_id())
SSID = UNAME + "-" + UNIQUE_ID[-4:]The primary limitation being that MicroPython for the micro:bit doesn't have the binascii library. Instead a list comprehension is used to properly format the binary machine.unique_id() into text.
There's a lot of duplicated code across all the devices. It all works, but there are some devices with more 'correct' code than others.
Please check the Espressif README for specific information.
| Board | Version | ID / Folder Name | Feature | AD |
|---|---|---|---|---|
| Raspberry Pi Pico | 1.24.0 | RP2-3238 | ||
| Raspberry Pi Pico W | 1.24.0 | RP2-4535 | ||
| Raspberry Pi Pico | 1.24.0 | RP2-5936 | ||
| Raspberry Pi Pico 2 W | 1.25.0P | RP2-6F97 | ||
| Raspberry Pi Pico | 1.24.0 | RP2-8721 | ||
| Raspberry Pi Pico W | 1.24.0 | RP2-9633 | ||
| Raspberry Pi Pico 2 | 1.24.0 | RP2-EC93 | Running RISC V Cores | Yes |
The Version column is the MicroPython version in use. The letter P next to a version stands for Preview.
The AD column means under active development at the moment.
Please check the micro:bit README for specific information.
Copyright 2024 William H. Beebe, Jr.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
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