Installing a rooftop solar panel system at our house was not a simple decision. In Bulgaria, household consumers have access to some of the lowest electricity prices in the EU, making it challenging to financially justify the cost of a…
The PS Thermo is a smart thermostat project developed by me, consisting of a control hub (that also acts as a gateway) and various sub-GHz RF wireless sensors/actuators. In essence, it is a much more advanced version of the BBoilRF…
I recently spoke with a friend of mine, who is now a software development team manager in a Fortune 500 listed company. He shared with me that his managed teams work using agile methodologies and consist only of software developers.…
While delivering on the promise of streamlined efficiencies and operational insights, smart IoT devices also present a new and more widespread threat to users and personal data. No one really needs reminding of the security implications of IoT. Think of…
My front gate has joined the Internet of Things and is now controllable from my phone. The sliding door opener is a Beninca BULL 5M. The project is DIY, based on ESP8266 + MQTT and I can now open/close/read the…
Modern HMIs are built as graphical user interfaces (GUI) with touch-based user interaction. Complex HMI development is always challenging because of the dynamic nature of the required behavior, underlying functions, and graphical design. Building a PoC prototype through code is time-consuming,…
I decided to test a 3.5″ TFT version of the TFT32 project as the original version’s 2.4″ 320×240 TFT is a bit small-ish. The TFT I chose is an ILI9488 480×320 3.5″ with resistive touch. The upgrade was pretty straightforward,…
As an IT team manager, I am responsible for forming highly engaged and efficient teams. Building an agile team requires a fine balance of skilled and motivated people, fine-tuned processes and proper tool selection.Put too much focus on people and…
I did a tech talk about my ESP32 based IoT control hub project on Feb 5th, 2019 at Work & Share Coworking Space Sofia. Over 100 people signed up for the event organized by DEV.BG, it was a pleasant surprise…
Performing Over-The-Air firmware update over a slow/unreliable internet connection may be challenging. I have had many cases, where the edge nodes to be updated are in a remote rural area with a 2G modem internet connection, and pushing a let’s…
My recent IoT projects are capable of performing OTA firmware updates, I have previously blogged about the importance of this capability. I normally use MQTT over SSL as a means of communication between the edge nodes and the cloud backend,…
Accurate time/date information is crucial for the correct operation of IoT nodes. From a security perspective, time/date information is necessary to perform SSL certificate validations. If your embedded device’s clock isn’t accurate, you can’t ensure the presented server certificate hasn’t…
I am working on a thermostat control project using the TFT32 hardware, let me share a video of the Wi-Fi configuration GUI (still work in progress). The Wi-Fi provisioning via GUI addresses one of the significant challenges when setting up…
Those of you that follow me on Twitter might already know that I’ve been working on an ESP32 based IoT control hub/gateway project with touch TFT lately. Let me describe what problems I am trying to address with this project.…
We have a 4.88m x 2.74m x 1.22m (13m³) Bestway swimming pool in the backyard. We only use the pool when the pool water temperature is > 25°C, but it only happens if there are intensive sunshine and high ambient…