Arduino, Netduino, Rasperry Pi!

I changed the code a bit, added an LCD, and increased the antenna size of my old EMF detector. It's sensitive enough to detect the different speed settings in my ceiling fan. The numbers are unitless, thus are are only relative to themselves. I hope one of these days I can get my hands on a good digital EMF detector so I can calibrate mine and make something more useful.  I'll be posting more code and such for the project later this week.

This RFID reader can read key fobs Tags and credit card size Tags also.

I recently bought a Rigol DS1052E and have been playing around with the different functionality it has. Eventually I came to the point that I’d like to see what frequency does to various components and wanted to build a voltage controller oscillator (VCO).

Interested in adding some NFC fun and excitement to your Raspberry Pi? You're in luck! 

One of the big advantages of Linux is that it includes a large number of stacks that have been developed by the open source community, and you get to take advantage of all that hard work simply by using or installing the right library. 

NFC is no exception here, with libnfc having been around for a quite some time -- in fact, it's the original reason the NFC Breakout was developed!

Here is a tutorial from Maxim describing how to protect your 1-wire slave devices from overvoltage. If an application requires writing to EPROM devices after deployment, 5V devices need to be protected from overvoltage exposure.

When we step into the world of small and resource-limited single-chip microprocessors, fixed-point math operation can be an extremely useful concept, and in many instances it is the only way to avoid the dreaded limited precision floating-point...

Control, monitor and receive email alerts from home alarm system using a Raspberry Pi.

Sometimes you have to do something just because you can. Today was no exception. Take one Raspberry Pi board (Linux) and give it a dose of .NET loving…

I can hear people screaming NO! but it’s too late, I’ve done it.

To be honest, I’m not the first person to use .NET on the Raspberry Pi. In fact I used this installation guide to install Mono on the Raspberry Pi.

Raj writes that he's just finished a new PC-based heart rate monitor using Arduino and Easy Pulse sensor (see previous Easy Pulse post).

This Instructable describes an station to measure Indoor Environmental Quality (IEQ). This is a measure of comfort that is impacted by several factors...

This question came from figuring out how to drive an SPI chip over a few meters distance. Normally, you’re not supposed to do that: I2C and SPI in particular are designed for use on a PCB, i.e. distances in the order of dozens of centimeters at best. Fortunately, in this case speed was not an issue, so what if we simply take the clock signal way down, to say 10 KHz (50 µs on + 50 µs off). Can we create a solid SPI setup across a few meters of wiring?

Congratulation !, you've got your new rasperry pi camera ! Isn't-it cute ? But after first try, you discover that it's not an usb-webcam. :-( Thus, OpenCV doesn't work natively. (forget cvCaptureFr...

 I've also been spending a lot of time shipping out QR clocks to my customers and handling customer service requests.  I've been really eager to post a final summary of the whole QR clock experiment, but I had to wait for the experiment to end first.

Now that all of my clocks are happily in the hands of their new owners, I can.

The Raspberry Pi is an amazing little board, with an amazing amount of power and functionality at an incredible price – it’s probably fair to say that our technology geek’s world will never be the same again, now that we have the RPi.

But it’s no speed monster…

Sometimes during development, it really gets in the way – especially when you’re used to working on a modern fast laptop, which is some 20 times faster (and that’s per-core).

So I decided to overclock one of my RPi’s, and see what it does. Overclocking in Raspbian is trivial with the standard raspi-config utility:

I have a Netduino plus at home and I love it. Not only can you use C# to write for it, but you get full visual studio integration including live breakpoints! I got the Netduino plus over the Netduino because the Netduino plus has a built in ethernet jack and ethernet stack support. This way I could access my microcontroller over the web if I wanted to (and who wouldn’t?).

For a little side-project I’m involved in (more on that in a future post), I wanted to try adding a little LCD screen with touch sensor to a Linux setup. Found this one at iTead.  There’s a little ribbon cable and adapter (just re-wiring) available for it, which allows plugging this thing into a Raspberry Pi. The nice thing about this screen, apart from being 320×240 pixels and 16-bit color TFT, is its physical size – just right for a stacked setup

If you're anything like me, you've wondered what happens in your garden while you're not watching. I wanted to know when birds are most active – are they busier in the evening or early morning? Thanks to the latest technology, now with a couple of taps of my smartphone I can monitor the bird activity in my garden from anywhere in the world.