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…
DIY swimming pool solar heater
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…
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…
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…
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,…
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…
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…
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…
proSmart
I have been busy starting up an exciting new project the last few months, a joint effort with a team of highly enthusiastic, hands-on, broadly skilled contributors with the goal to design and develop IoT home/industrial automation solutions. Together, we established…
Auto DST adjustment
We are close to that time of the year when Daylight Saving Time (DST) starts. It is intended to save on energy use, however, studies have found this to be questionable, even contrary – energy use increases in some cases. The change itself…
FOTA update without external flash for Atmega32U4 + RFM69
I’ve blogged before why firmware-over-the-air (FOTA) updates are a must-have nowadays, however, my old AVR+RFM based projects were incapable of that due to the lack of external flash to temporary store the new firmware before it is flashed on the chip.…
ESP32
I’m one of the lucky 200 that got their hands on the early beta of Espressif’s new ESP32 chip evaluation board. It is the “big brother” to the popular ESP8266, Espressif has though noted that it should not be treated…
Spectrum analysis with RFM12B
The comments to my last blog post got me thinking if I had chosen the right RFM channel at home, obviously if the channel is noisy that directly affects reception and increases the error rates. I use the default 868Mhz setting…
RFM69 to MQTT gateway using ESP8266
I’ve mentioned my plans for this project during the IoT hangout session few months ago, it has finally materialized as working prototype. The blocker so far was the lack of ESP8266 RFM69 driver and free time on my end, so I’ve…
Local hostname for connected devices
Now that we have connected our project to the local network, we are immediately faced with another challenge: how can we reach it? Using WPS/SmartConfig means we force the unit into DHCP settings mode, IP address is auto assigned by the router in…