Review on 🔧 ESP32 Basic Core M5Stack Development Kit: Extensible Micro Control WiFi BLE IoT Prototype Board for Arduino by Reginald Truitt

The M5stack is a fantastic little product, but it has some serious flaws. several posts about this on the support forum, but setting DAC to 0 didn't solve the problem. I had to cut the speaker wire to get rid of the unbearable noise. The second big problem was that the battery arrived almost empty. When I tried to use the device on battery mode, it turned off after 3 minutes. I've tracked charging with a USB meter and the actual battery capacity is 3mAh, just a fraction of the 150mAh it should be. The unit I received appears to be older, only has 4MB of flash instead of 16MB and arrived with the battery attached. It looks like the battery has been over discharged and damaged during storage. I would return the device because of this, except that I had already severed the speaker cable and I needed a more powerful battery for my application (GPS logger with display). The next problem I encountered was when trying to use the I2C port with the Sparkfun GPS. I've used GPS with Openlog Artemis and Adafruit Clue with no problems, but Openlog has no display and Clue has no SD card. The M5stack has both, which is why it struck me as the best logging device with live data display. However, when using Python, I2C communication was extremely unreliable, with frequent errors and data loss. Trying to track down the causes has been a disappointment as the Python documentation on setting UIFlow for M5stack is vague at best. It appears to implement only a subset of Micropython, with many features missing from the full distribution. The only "documentation" showing what features are available is the C source code on GitHub. Considering that the Basic Core does not have a real-time clock and limited flash memory, buying a newer M5stack model like the Core 2 or M5Go is the best choice for many applications.