I contrast to the very timing-sensitive one-wire protocol of the WS2812, the APA102 uses a standard two wire SPI protocol – one clock line and one data line. Each LED has two inputs and two outputs which can be daisy chained. At the first sight this may seem wasteful, but it has the advantage of being supported by standard microcontroller periphery and it is insensitive to timing variations. Due to the critical timing requirement it is not possible to control the WS2812 from SOCs with multitasking operating systems, such as the Raspberry Pi. This should not be an issue with the APA102. Furthermore, the data can be transferred at an almost arbitrary clock rate. I was able to control the LEDs with 4 MHz SPI clock without any hitch. It appears that the maximum speed is mainly limited by the parasitics of the wiring.
APA102 aka “Superled” - [Link]
An instructables on motor controllers for cheap robots by JayWeeks
Almost every robot needs to power a motor of some sort or another. Problem is that motors take quite a lot of power, compared to what most microcontrollers operate with. To solve this problem, robots use what is called a motor controller, which usually amounts to some form of electronic switch that can turn on a very high voltage, using a very low one. That’s what we’ll be making today!
Motor controllers for cheap robots - [Link]
by newtonn2 @ instructables.com:
This is a small bench power supply that I made some time ago, and because I was very busy I couldn’t do the instructable for it. I do apologise for taking so long, I hope it was worth the wait :).
After making my Mini Adjustable Power Supply I was very happy with it, but I was missing a more accurate control of the voltage and current. So I decided to make this slightly bigger (but still small) bench power supply.
DIY Small Bench Power Supply - [Link]
xristost blogged about the frequency counter module he made:
First of all I wanted a PIC microcontroller to do the whole job without any additional ICs. Also I wanted to use the the familiar 16F628A, but because one of the portA pins (RA5) can be used only as input I was short of outputs to do the job. Driving 6 digit 7-segment multiplexed display requires 7 + 6 = 13 outputs. The 16F628A has 16 IO pins, two of which are used for the crystal oscillator, one is for the signal input and other one can be used only for input, that leaves us with only 12 useful IO pins. The solution was to drive one of the common cathodes with a transistor, which opens when all other digits are switched off.
Frequency counter with PIC16F628A - [Link]
by Colin Jeffrey @ gizmag.com
Researchers working at the University of Missouri (MU) claim to have produced a prototype of a nuclear-powered, water-based battery that is said to be both longer-lasting and more efficient than current battery technologies and may eventually be used as a dependable power supply in vehicles, spacecraft, and other applications where longevity, reliability, and efficiency are paramount.
“Betavoltaics, a battery technology that generates power from radiation, has been studied as an energy source since the 1950s,” said associate professor Jae W. Kwon, of the College of Engineering at MU. “Controlled nuclear technologies are not inherently dangerous. We already have many commercial uses of nuclear technologies in our lives including fire detectors in bedrooms and emergency exit signs in buildings.”
Long-lasting, water-based nuclear battery developed - [Link]
by Kenneth Wyatt @ edn.com:
As you’re aware, I’m an avid fan of Thurlby Thandar Instruments (TTi) line of handheld spectrum analyzers, having purchased nearly every model as they are released. One of my long-term wishes is that TTi produce an analyzer with an upper range of 6 GHz. Well, my wishes have been met in their newly released model PSA6005! As I travel a lot in my job, I like to take the minimum amount of test equipment possible.
6 GHz spectrum analysis in your hand! - [Link]
by Martin Rowe @ edn.com:
Teledyne LeCroy has added a touchscreen to its WaveJet oscilloscopes. The WaveJet Touch, with a 7.5-in. touchscreen display, is based on the company’s WaveJet 300 series. The WaveJet Touch comes in two 4-channel models: 350 MHz (WaveJet 334T, $4200) and 500 MHz (WaveJet 354T, $5000). Both models have up to 5 Msamples of waveform memory, sampling at up to 2 Gsamples/s.
500 MHz Oscilloscope for $5000 and a touch screen, too - [Link]
Kerry D. Wong writes:
I just got myself a couple of Arduino Due boards. While they were released almost two years ago, I have not really got a chance to look at these until quite recently. Arduino Due is based on Atmel’s ATSAM3x8E 32-bit ARM Cortext-M3 processor. The processor core runs at 84 MHz, which is significantly faster than its 8-bit AVR counterpart ATmega328p which runs at 16 MHz. For an ATmega328p, the highest achievable PWM frequency is 8Mhz (square wave), so we should be able to generate much higher frequency signals on an Arduino Due. But how high can we go? Let’s find out.
On Arduino due PWM frequency - [Link]
The Wireless Inventors Kit for the Raspberry Pi (RasWIK) is an exciting and affordable addition to the Raspberry Pi. RasWIK demonstrates that with our leading edge technology anyone (and we mean anyone) can build wireless sensors and actuators , you do not need huge experience, a degree or even any tools. We show you even how to connect the devices you build to “the Internet of Things” (IoT) service providers such as Xively.
Getting started is just 5 simple steps:
1. Insert the preconfigured SD card to your Pi
2. Plug in the Slice of Radio to the GPIO connector
3. Turn on the Pi
4. Power the XinoRF development board
5. Lauch the Python based example application on your Pi
Thats it!……..you are now past step one of your journey to wireless nirvana
RasWIK – Raspberry Pi Wireless Inventors Kit - [Link]