The things I do
The ESP32 can be set to wake up from sleep due to one of several pins going high. Which pin caused it to wake up? This has been causing me a few headaches with my combined mailbox and driveway monitor because sometimes multiple pins can be high at once. While researching this I also discovered... Continue Reading →
The mailbox and driveway monitor that I built has a 12X2 LCD screen. I know these are not as fancy as many newer displays, but I like their simplicity. The screen in this project runs all the time, usually displaying the time. When mail is delivered, I wanted a coloured visual alert as well as... Continue Reading →
My main Arduino project for the last few months is trying to design and build a monitor that wirelessly sends an alert to the house when mail has been delivered in the mailbox or a vehicle goes through the front gate. I wanted the sender unit to be solar powered and use an ESP32. Reed... Continue Reading →
Update 14 April 2024: I've discovered that it is not necessary to calculate bitmask values for the ext1 external wakeup with the ESP32. There are predefined definitions that you can use. If you are interested check out my post ESP32: Wakeup from multiple GPIO sources and using predefined pin definitions instead of bitmask I'm currently... Continue Reading →
So you have a sensor connected to your microcontroller. How do you calibrate it, particularly if the values from the sensor are not linear? That's a problem I have thought about before and it came up again yesterday when I wanted a project to monitor a battery voltage level. The current project that I am... Continue Reading →
Most of my projects are fairly simple, low powered and run off 5V. Until recently I've used a cheap USB hub plugged into an old iPad charger. This actually worked fairly well, other than the hub connections being a bit dodgy. However, I wanted to be able to switch individual items on and off. You... Continue Reading →
A reader alerted me to the Tone function for Arduino. When I was making my WordPress hit counter I wanted to add in an audio alert. I preferred something other than a constant tone but thought I would have a go using the tone function. It turns out that the tone function is not implemented... Continue Reading →
One thing that I've noticed since the pandemic started is that there are far more online meetings in general and also interviews on TV where the guest joins remotely via the web. I like both of these. While not having guests travel to studios is usually fine, sometimes I feel it could easily improved if... Continue Reading →
When working with a project on a breadboard I've been caught with the supply voltage on the breadboard not being what I expected which resulted in the project not working as expected. To help prevent this I've bought some cheap mini 2 and 3 wire voltmeters. These sell for a couple of (AU) dollars. The... Continue Reading →
I remember seeing an ESP8266 project years ago that displayed a Youtubers subscriber count on an LED display. I was really impressed by that project. Recently I wondered if a similar thing could be done with wordpress.com stats, in this case not showing subscribers, but daily views. I did come across this response to a... Continue Reading →
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