XC9572XL CPLD development board are back in stock at Seeed Studio. CPLDs are programmable logic gate arrays which allow you to build custom logic devices simply by programing them. Get the XC9572XL dev-board for $15 and CoolRunner-II development board for $15.
Author Archives: DP
#FreePCB via Twitter to 2 random RTs
Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week: Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch […]
SIM900 breakout board
jechavarria writes: Hi! I want to share with you my last design. It’s a breakout board for the SIM900 GSM module. Fits in a 50×50 mm board, and has an IO connector with many of the signals you need to control it. Also, as the board is designed to work with a battery, it also […]
Nibbler 7400 4-bit custom CPU demos
Steve at Big Mess o’ Wires writes: I finished building my 7400 computer, and posted some demo videos here Via the forum.
mbedR3uino: mbed adapter for Arduino shields
Dave VW shared his project mbedR3uino in the forum: The mbedR3uino is a vertical shield adapter for the mbed prototyping platform. It provides compatibility with standard Arduino shields including the pins added to Arduino Uno R3 to make shields more independent between main boards. SPI, UART, I2C, Analog, Digital, and PWM pins are wired to appropriate […]
FriedCircuits now live!
Edouard informs us of FriedCircuits.us grand opening and by using the coupon code “OPENTEN” you’ll have 10% off : Over the past few months, we have diligently worked toward creating a one-stop-shop that offers tools & parts for sale as well as detailed documentation. There we hope to provide new products, tutorials and share FriedCircuits related projects. […]
USB random number generator
Dilshan Jayakody has written an article detailing his open hardware project the USB random number generator: This project is about USB port base true hardware random number generator and it is design around the avalanche noise which occurred in reversed biased P-N junction. This random number generator is design using commonly available electronic components. The core component […]
PCB Sunday: Pick your PCB
We go through a lot of prototype PCBs, and end up with lots of extras that we’ll never use. Every Sunday we give away a few PCBs from one of our past or future projects, or a related prototype. Our PCBs are made through Seeed Studio’s Fusion board service. This week two random commenters will […]
App note: Low-power design guide
An application note from Microchip: Lowering power consumption on PIC microcontrollers Low-power applications represent a significant portion of the future market for embedded systems. Every year, more designers are required to make designs portable, wireless and energy efficient. This document seeks to simplify the transition to low-power applications by providing a single location for the […]
Free PCB coupon via Facebook to 2 random commenters
Every Friday we give away some extra PCBs via Facebook. This post was announced on Facebook, and on Monday we’ll send coupon codes to two random commenters. More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three times every week: Free PCB Sunday. The classic. Every week, get […]
DIY digital wristwatch
Zak Kemble wrote a post on his blog detailing his digital wristwatch with a 1.3″ 128×64 OLED display, AVR ATmega328P microcontroller: The main incentive behind this project was to see how much I could cram, in terms of both hardware and software, into a wristwatch-like device that is no larger than the display itself. An OLED […]
M-Stack open source USB stack for PIC microcontrollers
Here is an open source USB stack for PIC microcontrollers and DSPs. It features a dual LGPL and Apache licenses making it suitable for commercial open source projects. So far it only supports the HID device class. A USB device stack is the software necessary to drive the USB device peripheral hardware on a microcontroller […]
DTMF decoder test circuit
Kenneth Finnegan writes: As part of a few projects I’m working on, I want circuits to be able to decode DTMF tones played over an amateur radio link for remote control. This can be done with a moderately powerful processor in DSP, but I opted to buy a handful of MT8870D dedicated DTMF decoder chips […]
Encoder library testing
Paul over at Dorkbotpdx writes: In a recent forum conversation, it was suggested my Encoder library has only been tested with rotary knobs and “lab” signals, not a high-res encoder turned by a motor, implying it might not work “in the real world”. So I build this little test board and made a quick YouTube […]
Arduino-controlled RGB LED infinity mirror
Ben Finio wrote this Instructable detailing his RGB LED Infinity Mirror: It’s an RGB LED infinity mirror that lets you toggle between an adjustable-speed color-fade mode and a direct-control mode where you individually set the red, green, and blue LED brightness levels. The primary inspiration for this particular project comes from this infinity mirror Instructable and Adafruit’s […]
A homebrew Tayloe SWR indicator
TJ Campie wrote a post on his blog detailing his DIY SWR indicator/bridge build: Dan Tayloe, N7VE, developed a really neat resistive SWR bridge that uses a simple LED to identify the dip in SWR on an antenna. QRPkits.com sells a nice kit of the bridge for just $15 and I recommend that if you don’t already have […]
#FreePCB via Twitter to 2 random RTs
Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week: Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch […]
Simple 50+ kHz logic analysis with ATtiny2313 and FTDI friend
Joonas Pihlajamaa over at Code and Life writes: While banging my head against the wall with debugging my PS/2 keyboard thingy, I really wished I had a dedicated logic analyzer (preferably with PS/2 decoder, but even raw binary data would’ve been fine). So I decided to try out a long hatched idea – combine an […]
400VA AC light dimmer
Mike over at Electronics-Lab shared his simple light dimmer project: This is a simple TRIAC AC load dimmer used to control the power of a resistive load such as incandescent lamp or heater element. The max load it can handle is 400VA. Such a circuit is often found on cheap commercial light dimmers and is proven to […]
PICkit3 external dual power supply (3v3-5V) circuit
Giorgos from PCBheaven wrote a post detailing the build of his PICKIT 3 external dual power supply: First of all, why… Why use such a circuit since the PICkit 3 has a built-in power supply software controlled. There are basically two reasons to build this circuit: First of all, it may happen – The internal PSU […]