People-Tools-Processes

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 tools development, disregarding processes, and you get a disorganized team. The lack of proper tools…

DEV.BG tech talk #3

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 to see so many IoT enthusiasts show up – thank you! Unfortunately, I wasn’t allowed…

ESP32 OTA firmware update using MQTT over SSL

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, and the devices are subscribed to a dedicated ‘firmware notifications’ topic that alerts them of…

Thoughts on time/date management on IoT nodes

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 expired, or is not yet usable, leading to connection rejection. In that case, your device…

TFT32 Wi-Fi configuration GUI

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 an IoT product – the initial setup. I have already blogged on this subject a…

Enhancing my ordinary IP security cameras with AI

Artificial Intelligence is quickly becoming an important ingredient for IoT projects’ success, a requirement for unlocking its full potential and providing a competitive edge to those that embrace it. AI naturally integrates into existing connected sensor/actuator networks and immediately adds measurable value. It was hard to imagine until recently, that AI will be so easily…

DEV.BG tech talk

I will be doing a tech talk on topic “Hardware and firmware considerations when designing low power battery operated wireless edge nodes for Internet of Things applications” at an event organized by DEV.BG. Join me on April 18th, starting 19:15 @ IT Step Academy. If you are in Sofia, you are invited to join. Page…

Where are the IT jobs in Sofia located?

I had a chat with a colleague the other day, discussing his property purchasing plans. He shared that the proximity to workplace is important for him. Planning in the long term, he asked me what districts of Sofia would be a good fit in my opinion, and I could only guess. Driven by curiosity, I…

Upgrading my fan coil thermostats

We use a DIY air-to-water heat pump for climate control (heating/cooling) of our house with a combination of water underfloor heating and fan coils in the rooms. The fan coils are equipped with basic thermostats that allow for heat/cool mode setting, desired temperature and fan speed. We never use fan speed setting other than lowest, as…

Internet connected fire/smoke alarm project

This project is an upgrade to a previous project of mine – the DIY IoT smoke alarm. It is a more advanced version that uses dedicated hardware rather than the generic “Funky” project + external components. In essence, the module integrates into cheap smoke detectors and provides wireless event transmission plus periodic battery measurements to…

High security key fob project

This project is about creating a high-security keyfob using Atmel’s ATSHA204 hardware authentication device. It was inspired by this post about security and signing. Many modern key fobs use various security techniques to prevent replay attacks, yet it turns out it is possible to hack even rolling codes. To solve this problem and have a key fob…

BBoilRF

This blog post is about a project I have been working on lately, the BBoilRF. It is a general purpose internet-connected relay actuator/gateway with support for low power, battery operated remote wireless sensor nodes. It was designed primarily for use as a thermostat with an option for wireless temperature sensors capability, but is highly configurable…