Using a cheap digital thermometer’s LCD display

I have one of the cheap DX digital thermometers laying around with the thermistor removed and used in another project. So I got an idea to try: use the LCD screen for visualizing data. The unit is driven by a thermistor: a variable resistor that changes its resistance in relation to the temperature. So, I thought the…

Flashing Arduino from SD card

Remote sketch uploading has been something I have long wanted for my projects. I can outline two major cases: 1) Remote flashing over TFTP – useful for remote locations where it won’t be convenient to go physically 2) Flashing from SD card – useful when you can provide firmware (compiled to .bin sketch) for downloading by end…

Single sided ATtiny84 temperature sensor PCB

Following the fiasco with the first version of the PCB, I have decided to create a single sided PCB so that the DIP socket that was causing me trouble is on the top. Here are the results, the PCB works great and the temperature is being sent every 60 seconds using the DS18B20 sketch. Page…

Arduino shield for energy monitoring

Few weeks ago I decided to teach myself Eagle PCB so I can put my current spaghetti-style solution for heat pump monitoring to some order. That’s just an excuse of course, I was curious how laying out a new PCB works to begin with. Since my current solution is based on the EmonTX, I decided to continue…