@tomasmcguinness

  • Record RTT logs from an nRF52840 with an RPi

    As I continue development of my Zigbee Flow and Return temperature sensor, I’m worried about the stability of my code. Once I’d finished the code, I deployed it to a nRF52840DK, connected to the mains i.e. on all the time. After the first few days, Home Assistant reported it as… Read ⇢

  • Detecting a 433MHz Kinetic Push Switch with an ESP32 – Part 1

    I recently published a video to my YouTube channel about Kinetic Switches. Kinetic switches are ones that don’t have a battery. Rather they use the energy generated during the push to send radio signals. Before December, 2024, I didn’t know they were even a thing. In my video, I look… Read ⇢

  • Zigbee F.A.R.T. PCB v0.2

    Learning from the few mistakes I made with v0.1, I’ve just send another revision to manufacture with aisler.net! This board includes several small tweaks. Changed terminal connectors I originally used simple screw terminals for the temperature probes. As I’ve figured out JST connectors and how to crimp them, I changed… Read ⇢

    Zigbee F.A.R.T. PCB v0.2

  • Battery terminals. Are you positive that’s the right way?

    When designing the PCB for my F.A.R.T. sensor, I had to decide which way the +/- terminals went. I had some wired connectors, which looked like this: I designed my PCB with this orientation of positive and negative and thought no more of it. However, when I tried to connect… Read ⇢

  • Zigbee F.A.R.T. Sensor code now available!

    It’s taken a long time to get here, but my Zigbee Flow and Return Temperature sensor code is on Github! https://github.com/tomasmcguinness/zigbee-nrf-flow-and-return-temperature-sensor Next Steps There is a small design flaw in my PCB, which needs to be resolved. I also need to confirm the sensor’s reliability i.e. it stays connected for… Read ⇢

  • F.A.R.T. Sensor PCB mistake

    After all the excitement of getting the PCBs for my F.A.R.T. Sensor delivered, I discovered that I had made a mistake! Let me show you what went wrong. If you look at the top right, you’ll see SW1. These pads are for a small push switch, which will act as… Read ⇢

  • Added Battery measurement to my Zigbee F.A.R.T. Sensor

    Whilst I waited for the arrival of my new PCBs from Aisler.net, I continued to work on the code for my Zigbee Sensor. Next item on my list was the addition of battery reporting. When running a device on battery, giving the user some idea of remaining battery life is… Read ⇢

  • My F.A.R.T. Sensor PCBs arrived today!

    A quick look at v0.1 of my F.A.R.T. Sensor boards! Read ⇢

    My F.A.R.T. Sensor PCBs arrived today!

  • nRF52840 ADC Pin Mappings

    I find myself struggling to remember the Analog to Digital converter PIN mappings on the nRF52840. To help, I created this simple table. This is for the aQFN73 variant, which comes on the Seeed XIAO nRF52840 I use the most. ADC PIN Name AIN0 A12 P0.02 AIN1 B13 P0.03 AIN2… Read ⇢

    nRF52840 ADC Pin Mappings