Aug 14 2020
Anticipating a lot of spare time and with rare good foresight, I bought an electric bicycle at the beginning of the COVID19 lockdown. I wanted a folding model so that it could be put into the car trunk and big wheels because the small-wheel folding bikes look strange to me. The Ancheer 26-inch folding mountain …
Permanent link to this article: https://w4krl.com/e-bike-energy-consumption/
Aug 10 2020
Soon after I got my Ancheer 26-inch folding electric bicycle, I built a data logger that directly measures battery voltage and current, and calculates wattage. It also records calculated energy consumption in terms of ampere-hours and watt-hours. It records this data on a microSD card every second. The datafile can be opened in a spreadsheet …
Permanent link to this article: https://w4krl.com/e-bike-logger/
Jun 02 2020
The ESP32 is a powerful microcontroller with many input/output ports. Specifically, it contains two 12-bit multiplexed analog to digital converters (ADCs) for a total of 18 channels. ADC1 is attached to eight GPIOs from 32 to 39. ADC2 is attached to 10 GPIOs (0, 2, 4, 12 to 15 and 25 to 27). There are …
Permanent link to this article: https://w4krl.com/esp32-analog-to-digital-conversion-accuracy/
Apr 02 2017
The ESP8266 using the Arduino Core reports Wi-Fi status with the WiFi.status() function. The D1M-WX1 Weather Station attempts to connect to Wi-Fi every 250 milliseconds until the “Connect” status is found. If this does not happen after 15 attempts, it prints the status to the Serial Monitor. Normally, the LED on the ESP8266 flashes five or six …
Permanent link to this article: https://w4krl.com/di-mini-esp8266-wi-fi-status-codes/
Dec 11 2016
The key to using solar power in an Internet of Things project is to put the microcontroller unit into sleep modeafter the sensors are read and the data posted to your IoT server. The NodeMCU and the Wemos D1 WiFi, a larger profile that mimics the Arduino UNO form, reliably woke from deep sleep. So …
Permanent link to this article: https://w4krl.com/sleep-mode-for-the-wemos-d1-mini/
Dec 06 2016
Recently the local Institute of Electrical and Electronic Engineers (IEEE) held two “hands-on” sessions to build an Internet of Things (IoT) weather station. We built it on a breadboard so that the attendees would not have to solder wires. Several of the participants have kept their stations on-line and two have placed the unit outdoors. …
Permanent link to this article: https://w4krl.com/external-sensors-for-weather-station/
Nov 24 2016
A solar power supply would be a really neat addition to any Internet of Things project. The ultimate goal would be to have a self-sufficient IoT device that could be remotely reprogrammed with the Over The Air (OTA) feature. A key to using solar power is to reduce the average power requirement of the IoT device. …
Permanent link to this article: https://w4krl.com/solar-power-supply/