Ok, so I’ve got a bit too excited about what I’m about to describe, but to be honest its quite cool (in a IoT nerd sort of way!).
For a while, when I was first cutting my teeth on Internet of Things stuff, I had an Arduino happily chatting to a nice 2 line LCD display. Nothing too fancy (except you could change the background colour!).
When I moved onto playing with a NodeMCU board, I realised that since the board is getting really small, then so does the display (for neat and tidy IoT devices anyway). After a bit of a trawl of eBay and various forums I came across some unbelievably cheap (£2.49!) 128×64 pixel OLED displays which it was claimed worked straight out the box.
The first order I made on eBay (which came from Malaysia, tracked for 29p!) didn’t make it past Heathrow. Now to be honest, its really rare that stuff goes missing in the post these days, and most orders only take about 12 days to arrive. But it’s gone, somewhere, so I decided on a UK order costing £5.98, so twice as much!
But it arrived today, first class, and after work, I sat down to get it plugged into a breadboard and onto the NodeMCU. After a entering a bit of code I found into ESPlorer, and uploading it, the code ran… …and the screen was blank. It was then I realised I’d put in my usual 5 second pause (see here why) and then the screen sprang to life!
The code itself sets up the NodeMCU to scan for all visible access points and their power levels, then display them. To my surprise (because generally these things are never THIS straight forward) it worked brilliantly.
“So why so excited?” you ask. Well the principle of getting a small display to work means I can now progress with the creation of some really small devices each of which can carry out monitoring tasks, but also display a nice local status of what its up to. I’d previously used a couple of LED’s flashing in certain sequences when the device was unplugged from the PC to give me an idea of its status. I can give up on my learning morse code and move to normal text!
Finally, why the 2p in the photo/video – well it’s just to convey how small but capable this stuff is!