ESP32: integrated the YL-69 for moisture-metering, also fried my first BME280

Written by  on March 12, 2019

Acquired a Bosch BME280 for improved humidity, air pressure and temperature-measurement (DHT22 can’t read barometric pressure) and tried to attach it via I2C.
Let’s keep it short: the sensor got very hot after several tries to find the correct wiring. Even using the i2c-scanner testprogram did not yield any results. But I learned how to use the breadboard more effectively. The burnt IC will be sold as ‘Lehrgeld’ 😉 (Oh, the days when I fried my AMD Duron, because I thought that a CPU won’t heat up so fast at boot. Boy was I wrong.)
Integrated then at least via analog reading the YL-69 moisture sensor. Worked well and on first try. Guess I just need to read much, much .. more about I2C, wiring and the sensors.
Another lesson learned: if you want to see really badly structured, basic coding: check tutorials for microcontrollers :/ (especially mine ;))
Code is committed and pushed to github.
Output is something like:

breadboard-setting featuring a Haworthia and WerNO!:

ESP32: first hands on MAX7219 and WiFi

Written by  on May 29, 2018

For an investment of 80-90 minutes time I am quite happy about the result and amazed what sohisticated capabilites are offered at some really easily accessible level.
What has been achieved so far?
* setting up a working Arduino Studio 1.8.5-environment with ESP32-toolchain on a Win7-laptop (not my favorite, but Linux-PC was blocked)
* setting proper options to the IDE to make the examples compile and upload via serial to the board; learn how to use the integrated serial-monitor
* finding the proper PIN-setup for the MAX7219-LED-display (just one module – for now) and setting up the library
* playing around with the WiFi-functionality (scanning for networks)
* putting both tasks (network scan and led-output) together and running into the first “I need threads”-pit

[Video was taken at an early stage: a static string is displayed.]

Of course, THIS is nothing, just the very first tiny baby-step. Everyone is able to achieve this, because almost no creativity needs to be invested.
But: configuring all the necessary tools was already a pain in the ass. Of course, just read the manual(s) [..]
But this is not a “unwrap and press start”-toy, so the learning-curve was steeper than expected.
But I did it. And I look forward. Especially to put some threaded application on the MCU, because – why just run one thread, when you can have two? 😉

[The MAX7219 and the ESP32-dev-board from MakerHawk hours before the first test run. Battery pack not included.]