Monthly Archives: December 2015


Just a little sidetrack while I wait for some stuff to arrive in the post to test my Pi Zero…. I’m using BLYNK (with issues) for controlling my heating – but as you may know, switching between 2 installations of Blynk is a pain involving logging out and back in. So this morning I thought I’d take a look at EMONCMS purely from a monitoring perspective.  It’s all free – you simply get an account – and in my case grab the EMONCMS NODE for Node-Red and start firing data at it.

So, this morning I know nothing – here’s my current dashboard.


As you can see monitoring 3 separate locations (my litttle ESP-12 boards – incidentally the Hollyberry one is now running on Espressif SDK 1.5 no problem) – and on the bottom right is a nice voltmeter checking my Pergola battery voltage.

Essentially given the address of the EMONCMS server (which can be theirs or you can have your own on a Raspberry Pi) and an API key, you just fire things like “is_temp:18” at the server and the values end up in a FEED which you then attach to one of the widgets – all very simple once you get into it.

Now – does anyone know of better/more flexible free IOT dashboards…


Wio Link

tmp4550You may recall I did a write-up on some neat little easy to use ESP8266 modules a while ago:

  • Visual Configuration
  • OTA (Over-The-Air) Firmware Updates
  • Plug and Play Groves
  • IFTTT Application
  • Android & iOS APPs
  • RESTful APIs

Lots of units that simply plug together. Well they’ve just been in touch to say they’ve changed the name and are on Kickstarter. They sent me a set of plug-in modules and while this will never be the cheapest option it is awfully handy if you’re not a dab hand with a soldering iron.  Here’s the link.

Oh, yes, it stands for “Wireless input and output to link everything” -  well, there you are.


Pi Zero Suicide

Ok, maybe it’s not THAT bad. I hooked up my Pi Zero to a Wi-Pi controller by taking the WIPI out of it’s shell and hardwiring power to the end power connector – and signals to the second usb connector as here.

I then grabbed Berryboot (original, not the Pi2 version) and altered the files as here. 

I made sure that the files were in Linux format (I used Notepad++ which can save in the right format). Popped in the MicroSD…. plugged in USB power to the end connector and… nothing – not even a flashing light.

That’s it. Not a clue what I did wrong and guess what – I only managed to get ONE Pi Zero!

So here’s an update. With the Berryboot code for the original Pi, nothing happens. With the Berryboot code for the Pi2, the little green light comes on – so it is reading the SD… but nothing else happens. As yet I’m not seeing anyone else having managed to get the Pi Zero working with Berryboot.


Espressif ESP8266 New SDK Update

You may be aware that ESPRESSIF have released a new update to their SDK which now stands at version 1.5

I’ll be interested to hear what experience other folks have of this..  On compiling my normal home control code which has worked without modification since version 1.0 I got this..

LD build/app.out
c:/Espressif/ESP8266_SDK/lib\libwpa.a(wpa_auth.o): In function `wpa_receive':
(.irom0.text+0x9a0): undefined reference to `aes_wrap'
c:/Espressif/ESP8266_SDK/lib\libwpa.a(wpa_auth.o): In function `__wpa_send_eapol':
(.irom0.text+0xd73): undefined reference to `aes_wrap'
collect2.exe: error: ld returned 1 exit status
mingw32-make.exe: *** [build/app.out] Error 1

and in the update info from Espressif they say ….

User application needs to add "-lcrypto" in '" area of Makefile.

Well I don’t have one of those in my Make file.

Not a good start, what? But there is a simple solution (not quite what it said on the Espressif forum)  - see the comments!