This is good looking and practical device that may be useful in many areas where count down timer is needed (no bombs please). Its time can be adjusted in range from 1 minute to 99 minutes. It displays time sequence on BCD decoded 7 segment LED display. When count down finishes – timer sends a control signal to relay.
Complete design is made on wiring technique, so no PCB is available. Project is very well described with circuit operation animations what is really helpful for circuit beginners. Source code is also documented well with flow charts. Assembly code and hex file may be downloaded here. [via]
Adjustable count-down timer with PIC16F84A microcontroller - [Link]
USB-LED-Fader can control up to 8 LEDs with individual brightness waveforms. Its command line tool can easily be integrated into scripts to implement a status display for computer load, mailbox status, network load, video recording software or similar background tasks.
USB-LED-Fader - [Link]
Turns out that a Ping Pong ball makes a reasonable LED diffuser. Just drill a hole and insert the LED. Easy micro Locnar! With an RBG LED this could make a nice system indicator. Maybe build a strip of these indicators to make several status indicators. Each server gets a mini orb to show it’s online status, maybe each email account. How about a ball of balls, each with an RGB LED… [via]
Ping Pong Ball LED Diffuser - [Link]
Josh writes -
I’m making a Knight Rider (KITT) Light Bar to celebrate the premier of the new Knight Rider Made-For-TV Movie. I’m using an Arduino Diecimila board and 18 LEDs.
Materials (so far): FedEx box (temporary; looking for a suitable plastic container) with black construction paper for the housing. Arduino, 18 LEDs (wired to 9 output pins on the arduino – two LEDs in parallel per pin), 9 75 ohm resistors (note, 75 is not the right value, but they were the closest I had). The faceplate is made of cardboard, tissue paper (light diffusion) and some cheap car-window-sun-shade-material I found at Target. [via]
Make a Knight Rider bar - [Link]
In this article Juan Mateos creates a PIC version of the Tengu companion. Tengu was originally developed by Crispin Jones as a USB controlled LED matrix that made faces and lip synced to music or other sounds it hears with a built in microphone. Juan created a PIC microchip version as an exercise to learn more about microcontrollers. He provides schematics, PCB designs and source code for his version of the Tengu in this article. There is also a detailed video showing his Tengu in operation with descriptions of the parts and function.
PIC Based Tengu - [Link]
Evil Mad Scientist Laboratories gets up close to some LEDs, and takes a peek beyond the light:
I took some close-up pictures of LEDs to get a look at what’s inside. These are just standard T-1 3/4 (5 mm) package superbright LEDs with clear lenses, one of the most common types, and I took the photos by placing my lens of my camera (Canon S3 IS) right up to them. [via]
Peeking inside some LEDs - [Link]
Latest Gadget Freak from Design News, a special Vday one! -
Looking for cool way of wowing that special someone on Valentines Day/birthday/whatever? Build her a flashing heart made from LEDs driven by a programmable microcontroller. Les’ gadget is simple to build and made from easily-obtainable parts. The unique thing about this design is the LEDs are in an X-Y matrix so each LED is addressable. This allows an unlimited combination of displayed patterns for the heart — not like some other designs out there! Source code and schematics are all available here and if you’re not into hand wiring, even the PCB can be had for a small fee. Diamonds may be a girl’s best friend but gadgets are forever. [via]
HOW TO – Build a flashing heart - [Link]
Rob sent in the latest gadget freak, he writes -
Seeing great potential in a normal, off-the-shelf product, Pete Griffiths designed a circuit he popped into the lamp to give it a new lease of life. His design combines a PIC and three constant current buck converters to create the RGB LED controller. This controller drives the high power 350mA LEDs using PWM to control the LED brightness. By driving the red, green and blue LEDs with varying pulse widths the controller can generate up to 16 million colours using fades, strobe and static effects. Who says you can’t give the humble lamp a nip and tuck? [via]
RGB LED PWM Driver for High Power 350mA LEDs - [Link]