I was one of those geeks that had their alarm clocks set on February 29th this year to become quickly disappointed understanding that the initial batch or Raspberry Pis was sold out in seconds. Later on when things settled a…
Measuring the solar yield
As I already mentioned before, I have an non pressurized evacuated tube solar water heater on my roof. In that same post I outline the possibility to calculate the solar energy that will fall on a flat surface (panel) with…
Thoughts on the Solar Energy Calculator
In my previous post, I outlined how to calculate the solar energy that reaches a solar panel in any orientation at any time. In the mean time, I created an emoncms input processor that calculates the momentary yield based on…
Calculating the available solar energy and logging it to emoncms
I have been experimenting these days with the possibilities to calculate Sun’s position and the light intensity in kW/h that will be available for my 2.088m2 evacuated tube solar heater. I wanted to log this in emoncms and visualize as a baseline to compare…
TinySensor’s SD card power consumption worries (and solution)
One of the things that has been bugging me recently is the power consumption of the SD card that I now have in the Tiny Sensor v1.2 design. I intend to power the sensor either via an external source (2xAA…
Toying with ATTiny84 and SD card in Arduino IDE
As I mentioned in my previous post, I tossed in a SD card port for the TinySensor v1.1. I wanted to give it a live test and see if/how it works prior to submitting the PCB to the fab house. So I…
The Tiny Sensor gets a SD card port
I had some space left on the TinySensor v1.0 PCB, plus I left myself few days to think before ordering the first batch, so I decided to throw in a SD card port. I didn’t want it to be anything…
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…
Tiny Sensor plans
I have been working this weekend on improved version of the ATTiny84 remote sensor, this time I will use a PCB fab house to make at least 15 pcs of the PCB. The improvements over the old hand-made PCB are:…
Downloading an Arduino sketch from Internet to SD card for flashing via the SD card bootloader
With the SD card bootloader ready, I thought I need a mechanism to be able to download firmware from the Internet and save it to the SD card, so that upon the next reset, the Arduino is re-flashed with the…
Using the Sensing Shield for logging solar hot water tank temperatures to Pachube
A local forum guy asked me to help him setup a system that logs his solar hot water tank and few other temperatures. The thing is he wasn’t sure how many temperature sensors he’d use and wanted to expand as…
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…
Store opened
I have decided to open a symbolic store on this site, where I will be selling some of my more or less matured projects. As a start I am offering the Sensing Shield PCB and will expand the products as they…
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…
Remote sensor’s PCB is a failure :(
Apart from the pathetic etching job on the PCB I described yesterday, I found out this morning that I also managed to etch the kitchen sink and made wife unhappy. It have been warned not to pour ferric tri-chloride in…