July 07, 2021

MySQL and NodeRed

Updated 2021-07-07 !

Sometimes the syntax for the Javascript in Node-Red is a little hard to get, despite some Googling. This was evident when i tried the run the "
node-red-node-mysql" node inserting data in a MySQL database.

Also timestamps in different environments are a little complicated.

So this post will cover both areas with some code examples done on a Raspberry Pi.

July 01, 2021

Raspberry fan control, Node-Red


Updated 2021-07-01 !

Do You want to have control over the Raspberry Pi(RPi) ? 

Functions
  • CPU Temperature
  • CPU Load %
  • Free RAM %
  • Disk Usage %
  • Shutdown and Reboot buttons
  • Fan PWM control via GPIO
Other NR posts on this site

June 15, 2021

Volvo Penta NMEA 2000 Gateway

Updated 2021-06-15

It's always nice to have ALL information at the same place, navigator/plotter, when You are out with the boat. 

What could be missing is the engine information/data. If You have a Volvo Penta from 2006 or later it could be pretty easy.

There are some "standard" NMEA 2000 gateways to choose from, for example; 
  • Volvo Penta has it's own 22813366, 3889758
  • Raymarine ECI-100
  • Maretron J2K100
  • .....

May 21, 2021

HomeKit bridge with Z-Wave


Updated 2021-05-21 !

These devices are available for Apples HomeKit. The devices are Bluetooth, BLE, or WiFi connected so it could be a limited range in Your house.

The Z-Wave solution have a smarter setup running on a type of network called a "mesh network". One Z-Wave product will pass the signal along to another (“hop”) until the final destination is reached. Every device, not battery charged, acts as a messenger; the more devices you have, the more powerful and strong your network is.

Raspberry USB SSD boot made simple ? Check link 

April 25, 2021

IKEA Bäve dimmer hack II

Updated 2021-04-25 !

Dimming not dimmable LED, IKEA Bäve, produced before 2019-11 













In former post I used a Fibaro Z-Wave RGBW controller but in this post I will use an IKEA original !

April 15, 2021

Homekit, temperature with DS18B20

Updated 2021-04-15 !

A cheap and simple way to measure temperature, and have it displayed in the Home app, is to connect one wire (1W) DS18B20 (DS)temperature sensors direct to the Raspberry Pi(RPi) and install a DS plugin.


This assumes that You have Homebridge up and running on a Raspberry Pi 

Check this post !!  "ANY" temp source can be HomeKit enabled.

March 22, 2021

Wordpress with PHP Everywhere

Sometimes you have to handle things in Wordpress that you can't find any plugin for.

In our case I had to visualize a list from a MySQL database and in another case I had to fetch data from another website.

In both cases I solved it with inserted PHP code which is executing and getting the info.

March 13, 2021

SignalK switch with NodeRed and WilhelmSK

Updated 2021-03-13 !

Here I'm trying to do the "ultimate" SignalK switch blog post including(no N2K)
  • Shelly 1 as the hardware switch
  • NodeRed as the function engine
  • NodeRed dashboard as input/output interface
  • WilhelmSK as input/output, check picture
  • A http endpoint as state sensing
The post is ment to be a template where you can pick the parts which are right for your setup.

February 15, 2021

Raspberry Pi measuring Voltage

I'm always a little confused that as soon as someone wants to get an analog measure to a Raspberry Pi(RPi) they are often taking a detour via an Arduino/ESP or some other microcontroller. 

Why not just take an Arduino peripheral and use it together with a RPi ? 

In my case I needed to measure the voltage across a fresh water tank level sensor in our boat, but i could be any DC voltage. Hints for sending the data to a Signal K(SK) server is found below. 

In this post I will use an ADS 1115(AD), or ADS 1015, as AD converter.

January 01, 2021

Scanner GUI with NodeRed

In a former post I installed CUPS printer software for a Cannon printer. The scanning functionality is supported by the package SANE. But there is no nice GUI for the scanning function so I made one, with NodeRed(NR), which I really think is "wife" enabled.



December 27, 2020

Homebridge, retrieve accessories information & status

Having Homebridge(HB) up and running it's simple to retrieve and visualize status or measurements from accessories.

For example I'm using the Aeotec MultiSensor 6,(AM6), via the z-way plugin, where I'm sensing the light level. Since Im living in northern Europe it's not very accurate to switch the indoor lightning by sun-rise/set. So instead I'm using the AM6 together with the EVE app to switch the lightning. 

To visualize the measured values over time I'm using NodeRed(NR) and a HomeBridge plugin

December 15, 2020

Free Gmail mail merge with Sheets

There are several mail merges applications where you can merge information from Google:s "Sheets"(GS), but not so may free ones that are good.

The point using mail merge is that you can personalize your outgoing mails and you will fore sure get a better response rate.  

There should also be said that if you are having a free Gmail account you are limited to 100 outgoing mails per 24 hours.

The first application, free !, handles the merge via a GS with a built in JavaScript macro and in the second application, 25 free mails per 24 hours(limit in app), the merge is done via an installed GS add-on with many nice functions.

November 15, 2020

Eniro charts using SignalK & Freeboard

Do you know about the SignalK workspace at Slack ? It's a really nice space where you could meet the developers and also get support.

If you don't are active there you can get an invite filling in your e-mail adress at

I'm following the dialog on Slack and for some weeks ago I stumbled over a post from @chris saying that you could get, with internet connection, the online charts from Eniro displayed in Freeboard. As you see in the picture it's just for the Nordic countries.

Another post installing offline charts.

October 15, 2020

WeatherLink weather template

Updated 2022-02-21 !

If You are interested in building Your own weathersite with information from Davis Weatherlink(DWL), and don't are a skilled programmer I can really recommend Node-Red(NR). In this post I give an example how to start with the NR dashboard GUI and DWL V1 API.


!! Please note new version with the latest v2 API !!

If You want a more advanced weather site/template this is a very nice one coded in PHP.


October 10, 2020

Raspberry and external storage/disk

There is a post, link will follow below, from the Raspberry Org site which is very informativ and handles how to connect your external hard disk, SSD, or USB stick to any of the USB ports on the Raspberry Pi(RPi), and "mount" the file system to access the data stored on it. 

So there is no need for a rewrite and this post will therefore continue with how to connect to a Windows server, (Other SMB or Samba servers will also work), both temporary and automagically at boot. 


Check this post RPi booting from an USB drive !


September 12, 2020

Kamado gasket glue

The gasket on our Kamado Joe was falling off after a very hot pizza cooking project. After some Googling, search link here, I found several post where people, to my surprise, used 3M™ Super 77™ Multipurpose Spray Adhesive.

I'm surprised due to it's just specified to handle up to 65 °C, 150 °Fahrenheit. 

It was also not available in the nearest shops so searching a bit further I found ...

August 30, 2020

Speedtest vs ISP and at home

Updated 2020-11-30 !

Sometimes you are doubtful about the performance of your home network, or versus the ISP, and wonder, where is the bottleneck ?

After some Googling I found some favorite applications, implemented on a cable connected Raspberry PI(RPi), which do the job so You can start measure and stop guessing.

A speedtest, 
  • checking Your ISP, with just a bash script
  • for Your home network

August 09, 2020

SignalK, stream data changes

Are You searching for a solution where You want to create graphs and gauges from SignalK(SK) data ?

Use NodeRed(NR), installed as a SK plugin, with the standard dashboard and it's easy to create info as seen in the picture. And this is without a database as InfluxDB and tools like Grafana.

You use the WebSocket interface and subscribe to any change of data from the SK server. 

July 10, 2020

Homebridge, autostart with systemd

Updated 2020-07-10 !

systemd is service manger which autostart jobs and it will even 
restart the Homebridge(HB) job if it fails !  

Keep it simple !! New post with a script which handles the setup automagically !! or use the latest HB install where this is included.

Other HomeKit posts on this Blogg

VHF antenna splitter, receive

During my AIS project with SDR:s as receivers I built my own antenna for use at home, a standard DIY dipol antenna

I connected the dipol, to SDR antenna input, with an a female SMA extension cable which I cut it in two pieces and soldered to the dipol. 

For the boat I didn't want an extra VHF antenna so....

July 07, 2020

SignalK, measuring temperature II

An introduction to the SignalK(SK), Marine application, is given here.

A very easy way to measure temperatures with SK is to use one wire (1W) DS18B20 (DS)temperature sensors. 

In a former post the DS:s where connected direkt to the RPi GPIO:s, but in this post they are WiFi enabled via the Shelly 1(S1). Alarms are also sent when the temperature exceeds a set value.

If humidity is of interest You can use a  DHT22 sensor instead of a DS sensor.

June 10, 2020

HomeKit, Z-Wave, Telldus Live, and...


Updated 2023-10-10 !

You can use one  Raspberry Pi to
  • Make Your home automation devices appear in the Apple Home App
  • Being the Z-Wave controller
  • HomeKit enable Your Z-Wave devices
  • HomeKit enable Your devices registered at Telldus Live
  • HomeKit enable IKEA Trådfri devices 
  • Homekit enable temperature with sensor  DS18B20
  • HomeKit enable Broadband speed
If You have other products there are more than 4200 plugins available

A new simple install  !! is found here so skip the below info if you aren't interested of the old way!


May 09, 2020

HomeKit showing Humidity & Internetspeed

From AppleWatch
Strange mixture ? Humidity & Internetspeed ? 

With HomeKit You can't show Your measured Internet speed in a proper way,  X Mbit/s. So why not show it in % ? the measured speed compared to the one You purchased from Your ISP(Internet Service Provider) ? 

So now You see the point..... Humidity is also in % and can be displayed in the Home app. The only "if" is that the speed is displayed along with a "water drop"..... but maybe You can live with that ? 

May 03, 2020

HomeKit with "ANY" temperature source

From AppleWatch
As long as it's possible to retrieve information, in some way, from a sensor OR a website/webserver, with temperature information, it's possible to show it in HomeKit with HomeBridge(HB).

In this post NodeRed(NR) is retrieving the temperature from Your selected source and is also acting as the WEB endpoint for the HB  "homebridge-http-temperature" plugin.

In my case I wanted an outside temperature so used the measurements from our Davis Weather station and their JSON REST API but it could for example be Your Raspberry CPU temp or showing the speed of Your Internet connection.

April 02, 2020

Underfloor heating hack

I have tried to find some basics how a standard underfloor control system is regulating the heating, but haven't, so started with checking up our own temperature control system from LK(TCS).

I used Node-Red, with Raspberry Pi(RPi), sensing when the TCS applied voltage to the actuator. Since the actuator is running on 24 VAC and the input on a GPIO PIN is maximum 3,3 VDC I used a optocoupler to level shift. Schematics below

Please find another post here where I realized, using Shelly 1 and NodeRed, the regulating of the underfloor !!