Veronica @ blondihacks, we are loving her site! – [via]
Now for something a little different. I was first exposed to computers back in the late 1970s and early 1980s. Suffice it to say, placing my hands on the keyboard of an Apple //+ was a watershed moment which pretty much set the course of my life from that point on. The heart of the Apple // was the 6502 microprocessor. I learned to program on that chip, along with millions of other people. It was the chip that brought computers and video games to hundreds of millions of homes and schools, and I think it’s safe to say that it sparked a revolution. The world was ready for personal computers, but all the contemporary CPU offerings (notably from Intel, AMD, and TI) were very expensive. The 6502 offered all the power of the others, for 1/10th of the price. You could find 6502s in the entire Apple // line (except the GS), the Commodore 64, the Vic-20, the Atari computers (except the ST), the BBC Micro & Acorn, the Atari 2600, the Nintendo Entertainment System, and many others. If you used a personal computer or played a videogame in the 1970s, 1980s, or early 1990s, there’s a very good chance it had a 6502 in it. It was arguably the first RISC chip, and the first to do pipelining. It has a clean, elegant instruction set and gets much more done with a clock cycle than anything else of the era.
Veronica @ blondihacks - [Link]
When building AVR DDS2 signal generator there were lots of discussions about signal conditioning in analog part of device. First argument was that LM358 wasn’t the best choice for this purpose. Another one pointed to sine wave that weren’t smooth enough.
As you can see there are some dents on it. Other waveforms also are distorted especially when higher voltages are selected. This definitely asks for better analog part. Some people suggested to replace LM358 with OPA2134, but it seems to be quite expensive choice. In my opinion low noise general purpose op-amp can be great too. I’m gonna give a try to Texas Instruments TL074 low noise op-amp. It is low power, high slew rate (13V/us) IC – almost five times faster than LM358 and for same reasonable price.
Modeling of analog part for DDS3 signal generator - [Link]
CdS (Cadmium Sulfide) photo-resistors are commonly used for detecting light levels. They are common, fairly cheap and easy to use. So whatʼs the problem? They are becoming hard to find. The reason is because of the RoHS directive. Since CdS cells contain cadmium, a toxic heavy metal, this important component is no longer stocked by major electronics distributors. The good news is that not only is there an excellent alternative, but it is more versatile and vastly cheaper.
If you guessed photo-diode you are close, but even better is the humble LED. The LED is even cheaper, more readily available and more versatile.
This tutorial shows how using only one digital pin. It also shows how an analog pin can be used to improve low light measurements.
Cheap Alternative for Hard to Find CDS Light Sensor - [Link]
XMOS, developers of the industry’s first even-driven embedded processor, are running a special holiday promotion for a select few hacker and electronics communites.
They are giving away free developer kits to anyone who can come up with an awesome project idea that uses one.
The XC-1A developer board features XMOS’s most powerful processor; a quad-core XS1-G4 and is a great platform to start any project, big or small.
Head over the www.xcore.com/promotion now to submit your idea and win a kit!
XMOS is giving away XC-1A developer kits - [Link]
The honor of having your own Google Doodle is bestowed upon only a few very special individuals like Gregor Mendel, Alexander Calder and Lucille Ball. Today’s entrant celebrates the 82nd birthday of the late Robert “Bob” Noyce, co-inventor of the microchip. After co-founding Fairchild Semiconductor and Intel, he mentored younger engineers to earn the nickname “the Mayor of Silicon Valley.” Surf on over to the Google homepage and you’ll see its logo imprinted over a microprocessor, which Bob helped to birth.
Google doodle celebrates Robert Noyce; Intel co-founder and ‘Mayor of Silicon Valley’ - [Link]
The design is based around the MCP1640 IC. It is a 350mA 500Khz boost converter with an integrated switch. Due to it’s design the device requires very few external components to function. One Inductor, two capacitors, and two resistors are all that is needed.
The efficiency ranges from 60% to 90% depending on the load and input voltage.
Single battery boost converter - [Link]
After my Masochist’s Video Card project won 2nd place in the 7400 contest, I got to choose one of many prizes being given away by Dangerous Prototypes. The prize I chose was the DE0 Nano FPGA development board, which, it turns out, is a pretty beefy little thing, despite its tiny size.
This article will look at how to build the same functionality that the Masochist’s Video Card (built only with 7400 logic IC’s) had, however this time we will use the DE0 Nano development board to complete the task, instead of wrist-breaking, pain-staking, masochist-loving wire-wrapping.
DE0 Nano VGA Output - [Link]
I had been reading on chaos generators in the past, and this e-mail got me interested again. Their design is somewhat complicated, with a total of 13 stages of 7 different circuit blocks. You can read all about it in the PDF they published
A much simpler chaos generator that can be built with a lot less components is called Chua’s circuit. The downside with this simple circuit is that you need an inductor which you might have to wind up yourself. Also there should be much less variety than in the waveforms of the Elektor circuit. It has so many stages that can saturate to give different waveforms.
Still, Chua’s circuit is very interesting to fiddle with. I haven’t built the circuit yet, but I did some simulations with LTSpice IV and here’s what I found out.
LTSpice simulation of Chua’s circuit - [Link]
Stephen Evanczuk writes:
Micro-harvesting, or energy scavenging, relies on extracting power from minute but pervasive sources of ambient energy such as light, heat, RF, or vibration. With piezoelectric devices, energy from vibration can supply low-power applications, such as wireless sensors that are difficult to reach and maintain, for equipment or structural monitoring. By following a few key design considerations, engineers can build applications powered by piezoelectric transducers from Parallax, Measurement Specialties/Schaevitz, and Mide Technology and power management devices from Linear Technology.
Compared to other micro-harvesting energy sources, vibration and motion are relatively robust sources of ambient power (Figure 1). Placed on motors, for example, vibration-powered sensors can harvest power precisely when it is needed during motor operation. In a practical application, the piezoelectric transducer would likely be used to charge a high efficiency storage device rather than provide power directly to application circuits.
Energy Scavenging with Piezoelectric Transducers - [Link]
Atmel launches digital audio development system – [via]
Atmel Corporation has announced a complete hardware and firmware digital audio solution aimed at simplifying the design of digital audio equipment for consumer, automotive and industrial applications. Based on the Atmel’s AVR UC3 microcontrollers, the Digital Audio Platform is specifically tailored for audio applications such as USB docking stations for smartphones and media players.
The platform comprises dedicated microcontrollers, evaluation kits and firmware IP. The firmware IP includes control and streaming interfaces for popular smartphones and portable media players as well as MP3, WMA and AAC decoders, USB protocol stacks, and a complete file system to allow designers to utilize mass storage devices such as USB flash disks and SD cards. The Digital Audio Platform is ideal for applications including docking stations, USB mass storage, SD card playback, car stereos, USB speakers, microphones, and various voice and music equipment.
Atmel launches digital audio development system - [Link]