ESP32 (more precisely: Heltec WiFi Kit 32 with onboard OLED display) WiFi WalkBy Signal Strength Plotter

Expanding on the previous post showing a restored out-of-the-box functionality, and inspired by the capabilities of the excellent u8g2 graphics library (all be it restricted by my limited imagination and capabilities), I have the pleasure to present Version 2 of the WiFi Scanner displayed onboard the ESP32.

This one only plots the top 3 WiFi Signals found (identified by router MAC address, not by name as you wouldn't believe the number of duplicate network names you'll find just walking around....) But, it stores "recent" signal strengths and uses that to plot a sort-of bar chart under the network of strength. I don't know how useful it is, but it's fairly nifty and I'm more proud than I ought to be about it.

Here's it running in a Generic Semi Public Location:

(image processed to disguise the terrible job I did of soldering on the pins)

Updated 2019-01-08 12:46: Changed the "replace with new network" code to zero-out stored and now invalid history for the old SSID.

HELLO (esp32) WORLD - a re-creation of the code running on my ESP32 Board when I got it

Wasted a number of hours this evening in re-creating the WiFi scanning code that was running on the board when it arrived (and which I immediately blew away with my first upload). Mostly this was a learning experience in the U8g2 driver but there's a bit of Arduino IDE learning involved too....

Here's it running:

(It's not identical to the original, in particular the font I've used is almost certainly different. And it doesn't display the logo on boot, mainly because I've got no idea where that logo is defined and I've got no inclination to find or create a new one).

Note that I'm explicitly not claiming ownership of the code, I've noted where I've heavily borrowed from. Mostly this is for my own later use if I have to build another dev environment, if I'm honest.

The original WiFi scanner is a built-in sample of the ESP32 board samples (File -> Examples -> (ESP32) WiFi -> WiFi Scan). This version started from the example written by Robot Zero One available here, but I modified it to use the page-buffer because I wanted to have control over font sizes. I'm still not 100% sure I'm Doing It Right because pushing stuff to the display seems to be over-complicated, but it does have the virtue of, you know, working.....