Voltlog #275 – CO2 Concentration Measurement System With MH-Z19B & CCS811

Welcome to a new Voltlog, you might remember these two sensors from a previous mailbag, this is the MH-Z19B and this is the CCS811 both of these report CO2 levels but they measure this differently and I’ll explain this in a moment. I got these two sensors in order to monitor CO2 levels in my home, to determine if the levels rise too much at night, especially during the winter time when we tend to keep the windows closed most of the time. I live in an old apartment building where there isn’t much provision for ventilation and so I suspect the air I breath during sleep is high in CO2 levels as it builds up over night.

In this video I’m gonna show you how I built the monitoring system using an ESP32 board that reads the sensor data and then sends it over the network to an MQTT server running on my raspberry pi. I then use node-red to insert the data into InfluxDB and then finally Grafana to monitor all of this data in a nice graphical user interface. The beauty of this setup is that all of this software is free to use and open-source.

Voltlog #274 – Installing Traccar GPS Tracking Server On A Raspberry Pi

Welcome to a new Voltlog, today I’m gonna show you how to setup your own GPS tracking server on a raspberry pi. It doesn’t have to be a Raspberry pi, because the software that we’re going to be using for the tracking server is available for Windows and Linux as well, so you could host this on your windows machine or in a virtual machine on a cloud service, it’s up to you, but in this video I’m going to do it on a Raspberry pi 4.

The idea started a couple of videos back, in Voltlog #272 when I got this GPS tracker disguised into a general purpose automotive relay. In theory this should come with free online tracking service on some Chinese hosted server but I wasn’t able to connect to that server and so I thought why not setup my own server and try to pair it with this tracker. So if you want to learn more about this tracker, checkout Voltlog #272 linked on screen right now and then come back to watch this video.

First step is to setup a fresh install of Raspbian, latest version from the source. Next step is to setup the tracking server, the name of the software is Traccar and here is their website. We’re going to be using the Linux arm release, because the raspberry pi runs on an arm processor. Next, your raspberry pi is likely sitting behind a router or firewall so you will need to forward a port so an external device like a GPS tracker can connect to our newly created server.

Next we can add our GPS tracker in the web interface of Traccar, on the left side I click add, choose a name for your device and fill in the 10 digit identifier which is this label on the side of your trackers case.The newly created device will be shown as offline until the server starts receiving data.

The final step is to configure the GPS tracker and these particular commands apply to the tracker that I am using, you might have to use different commands for a different tracker but the idea is to reset the tracker, set your admin number, configure the APN settings for your network operator, set the external ip address we saved earlier, the port is 5013. Set the upload frequency in seconds and enable the GPRS connection. Going back to the Traccar web interface, status should switch to online and we should start seeing data about our device.

Voltlog #272 – Car Relay GPS Tracker Setup CJ720

In this video we’ll take a look at the CJ720 car relay gps tracker, I’ll show you how to setup the tracker and how to get position information. I will show you what kind of commands this tracker accepts and I will also do a teardown towards the end.

For information on how to setup your own GPS Tracking server, running on a raspberry pi, using open source software, checkout Voltlog #274.

Voltlog #265 – FT232H USB to JTAG/I2C/SPI Interface With Python & PyFtdi

Welcome to a new voltlog, today we’re going to be talking about this little board which I designed and assembled myself, it’s a breakout module for the FTDI FT232H which is a usb to serial converter but with a nice twist. This particular chip from FTDI has the built-in Multi-Protocol Synchronous Serial Engine (MPSSE short) which allows you to run a variety of synchronous serial protocols like JTAG, I2C, SPI or simple bit-banging of IOs. You can imagine it can be really useful to be able to interface with a sensor over I2C or SPI straight from your computer over USB through this interface. You wouldn’t need an arduino or other controller in the middle if you plan to do some data acquisition for example.