ESP8266 Mesh Experiment

MeshIn case anyone else (like me) has been sitting on the shelf over this one – and would like to have a go at an ESP8266 mesh… we’ve been having a play.

Regular readers may recall I wasted the better part of a year with those AWFUL NRG24L01 boards trying to make a mesh and ultimately getting no-where – indeed I think it is the mere existence of that board that drove me to the ESP8266.

Fast forward to December 2017 - take 3 ESP8266 modules, run the same code on each of the three, attach a LED+resistor to GPIO12… take ESP8266 modules for a walk. One is in the house, one in the office out of range, the other in the middle sitting on my car in the freezing cold.   When all 3 are talking to each other you’ll see 3 flashes in quick succession…

Continue reading ESP8266 Mesh Experiment


Christmas RGB Animation

Cloe admiring my Christmas lights

My ESP8266 home control code contains not only RGB code for serial LEDs but also a complete programming setup to generate and loop sequences… and so with merely one wire and VERY  little work, we end up with some fancy animation.

Here we see an old, gutted plastic Christmas window decoration which WAS filled with old fashioned white lights but now has a string of 69 serial LEDs running animation around the inside.

I made one of these last year but when it came to trying out my animated LED Christmas lighting this year – nothing happened – dead. After wasting hours I remembered I’d changed the code earlier this year so for anyone using my ESP8266 software and wanting to knock up a quick Christmas animation – here it is…

Continue reading Christmas RGB Animation


Odrvm 4K Action Camera

Slightly out of the normal, I’ll grant you but I thought this was worth doing a short piece on because of an alternative use for this camera. So what we have here is the Odrvm 4K Action Camera, which comes as a complete kit, in my case from Amazon.

ODVRM Action Camera as WebcamHere’s the story. I’ve been looking for one of these for ages for Spain, I have a decent camera, an SLR which would be wonderful were it not for the weight. Despite a lifetime dabbling in photography, I’ve never gotten used to carrying around a large camera in the hot summers of Spain which is where I plan to be this summer.

I can’t tell you how many hours I spend trawling through videos on YouTube for an “action camera” capable of at least 2k video and preferably with a gyro to minimise shaking.

Simba on OdrvmWell I was just down to the last couple of cameras when I received an email from a company who wanted to know if I would check out their action camera! Next thing I knew I was off ordering a camera and spare batteries on Amazon PRIME for next day delivery and this morning, my parcel arrived – well, part of it. Not unusually for Amazon, there was a last minute hitch and the batteries won’t be here until next week.

However as it turns out the camera package comes with all sorts of mounts (I mean LOTS of mounts), the camera itself contains a battery and.. there’s a spare one in the box! The manufacturers claim 80 minute battery life but if we assume that means somewhat under an hour of video’ing, it makes sense to have a spare or two.

Odrvm 4K Action Camera

As you can see from the above, action is limited to no closer than maybe 6-9” – but beyond that is extremely sharp – this is shown in the video.

So, as requested I opened the box, described what was inside then went off into the freezing cold Bellingham winter air to take a video.

And that’s fine, no-one is suggesting using this as a top end video camera but with anti-shake it is pretty good for the money – however – that’s not all because it ALSO makes a very good webcam – better I may add than Logitech upmarket models I’ve tested.  So – when you’re not out taking mountain photos – this doubles up as a webcam while it is sitting charging – sounds like a good idea to me.

I did enquire and the sound level is fixed in the unit. Right now it is not possible to add an external microphone, this will likely change in future (if I were to do any serious filming I think I would record audio on a phone with proper external mic – I’ve yet to come across a camera built-in mic that is very good.







SI5351 Clock Generator

SI5351 Clock Generator

A short while ago I put together a little poor-person’s signal generator (or signal generator for people who only use them once a year). It is currently waiting for me to drill a tiny box to put it in. Meanwhile of course I’ve taken possession of a FeelTech function generator which does the same and more (albeit at a higher price).

All of that is very nice but the frequencies coming out of these things are no good for experimenting with microprocessors which might need 16MHz or much higher.

And so it was that a kind blog reader pointed me to the SI5351 clock generator board on AliExpress. This little beast claims to have 3 separate outputs able to handle 8KHz to 160MHz.

So, yesterday the board turned up. It comes unsoldered and requires that you solder a 7 way connector and 3 output connectors.  The former was easy, but as you can see by the mess of soldering, the output connectors are not trivial to solder on a tiny iron made for SMT work due to their bulk efficiently taking the heat away – I simply could not get enough heat in there to do a visually great job.

However, functionally the soldering was just fine so I went off in search of a test library for Arduino (always a good starting point) – of course there’s an Adafruit library but after taking a quick glance I decided you had to be a ham radio fan to get your head around the setup – and so instead went for this library.

Of the 7 connections you need only 4 i.e. ground, power, SDA and SCL (I2c). I hooked these up onto a board (with 2k2 pull-up resistors) – all running on 5v.  I ran the library and, well, it just works.

If you study the library there are a number of options – I chose to ignore them and go with the easy option.

#include "si5351.h"
#include "Wire.h"
Si5351 si5351;

void setup()
// Initialize the Si5351

si5351.init(SI5351_CRYSTAL_LOAD_8PF, 0, 0);

si5351.set_freq(810000ULL, SI5351_CLK0);
si5351.set_freq(820000ULL, SI5351_CLK1);
si5351.set_freq(830000ULL, SI5351_CLK2);

si5351.output_enable(SI5351_CLK2, 0); // turn off output 2

In the above example – output 0 is set to 81KHz, 1 is set to 82KHz and 2 is set to 83KHz – and output 2 is turned off.

It really is that simple – I found contrary to the advert that I could go down to 4KHz and as far as I can tell everything was working just fine at 160MHz – but my scope coughed up it’s lungs at anything over 120MHz.

The frequency values are shown to a resolution of 0.01Hz. If you want to use Hz just divide by 100.

Here’s the output when set to 1MHz.

If you look at my function generator code where I put the settings onto an SSD1306 display and had setting buttons and memories – it would take no time at all to modify that code to make this into a neat little clock generator unit.

1Mhz signal from clock generator

Now I just need some nuts and plugs for those small connectors… ideas anyone – I need nuts for them (front panel) and male connectors ???


IoD-09 Display from 4D Systems

tmpEEA6You may recall some time ago I reviewed some displays from 4D Systems – using an ESP8266 together with a touch display – and very nice too.

Well, the company just sent me one of the new IOD-09 displays and it is the cutest thing you’ve ever seen.

You will possibly be familiar with the little OLED displays I use a lot from the likes of AliExpress and Banggood (or Ebay for that matter) – the SSD1306 based units. They are amazingly small – but if course you then need a Nano or ESP8266 to drive them – boards invariably larger than the display by some way.

Continue reading IoD-09 Display from 4D Systems


FeelTech FY6600 Waveform Generator

Regular readers will know we just looked at a DIY signal generator able to generate sine, triangle and square waves. Breadboard, wires, you name it…  Well, this is NOTHING like that. 

If the simple DIY generator of a previous blog is not to your liking you might want to consider something like this Feeltech FY6600—50M Dual Channel Function/Arbitrary Waveform Generator supplied in this case by Banggood.

Feeltech Waveform Generator

Read on…

Continue reading FeelTech FY6600 Waveform Generator


VL53LOX Distance Measurement

tmpAE48The VL53LOX usually comes as a tiny board complete with regulator and is an I2c device capable of measuring short distances.  I thought I’d put it to the test.

The proper description which sounds very impressive is “Time of Flight (ToF) Laser ranging Sensor” – really?   Well, let’s see what it can do. AliExpress sell these for around £5.30 ($7.23) with free postage.

Attached to +5v, ground, SDA and SCL on an Arduino UNO (which means I don’t have to worry about pullup pins for I2c and it just happened to be sitting on my desk at the time) you could start by grabbing the Adafruit library and adding that to an Arduino setup. Read on…

Continue reading VL53LOX Distance Measurement


Boxes Galore

Boxes from Banggood

Nothing special - just boxes. Those with working 3D printers please ignore me. For the rest… I just took delivery of 20 boxes at less than 50p each and I think this is the best box purchase I’ve ever made – got them from Banggood though I’m sure you can get them elsewhere. The link is above.

Inside size is 50mmx70mmx 25-26mm deep. There is a keyhole in the back for mounting and vents top and bottom.

I have to tell you I have a million uses for these – you could easily get an ESP12 plus whatever sensor in there and having the vents at top and bottom is great. There are mounting posts in the bottom, 2mm x 62mm and you'd need holes 5mm dia.

Continue reading Boxes Galore


ZeroPlus Logic Cube

tmpE089I recently took a look at the ZeroPlus Arduino Starter Kit – well, this logic analyser is not a starter version! This particular model, the Lap-C 322000 has 32 channels  and a bandwidth of 75Mhz. It has 64Mb memory, 2Mbit per-channel depth and is the top of the line in the LAP-C range.  The unit comes complete with manual, probes and hard case and works on USB 1.1 and USB 2.0 – Read on…

Continue reading ZeroPlus Logic Cube


Arduino for Beginners

ZeroPlusWe rarely cover projects for beginners in the blog and I guess that’s because most of the people I know who are into technology have been there for a while.  But as I found out when I first started getting into Linux a couple of years ago, it is awfully useful if you have a helping hand!

Only this morning we discussed a power supply which required some soldering – and that, when you think about it is not something a beginner is likely to have.  In this blog entry we’ll assume a brain, a computer and a little money to buy this kit – looks like a great Christmas present to me!  Read on…

Continue reading Arduino for Beginners


ESP8266 and ATMEGA2560 Mega Board

ESP8266 and Atmega 2560You may recall my blog entry about my “universal peripheral” – using the little Arduino Nano or similar clones with an ESP8266 – with the former providing GPIO via an I2c connection.

Well, that led me to getting this little number from Banggood – the Wemos Atmega + WiFi R2 Atmega2560+ESP8266 32Mb Memory board.

It’s not 32 MEG of course – it is 4MB – but that’s the same as a normal ESP12. but with the GPIO power of an Atmega 2560 – all in one neat board.

Initial impressions – it looks well put together.  According to the underside, it takes DC 7-16v in – and has DC out at 5v 1.6A and 3.3v at 1 amp – so it actually is a little more than just the two boards – looks like there’s lots of power there for peripherals.

Continue reading ESP8266 and ATMEGA2560 Mega Board