Zoltán Gömöri writes: I started the development of the counter. First of all I should proof if I can create a display/button matrix which can handle the two display digit and the two pushbuttons. I picked the double multiplex display a fist of diodes and pushbuttons and a launchpad. Here is the result. I’ve topped the […]
Author Archives: DP
Emulating the Apple HD20
Steve at Big Mess o’ Wires writes: So how does it work? First off, we can assume that raw data bytes are sent and received in serial fashion using NRZI encoding on the ReadData and WriteData lines of the floppy connector. While the DCD documents don’t specifically mention this anywhere, it’s a safe assumption because […]
Pick and Place USB control software
Brian Dorey posted an update on his DIY Pick and Place machine USB controller board, we wrote about it previously: After completing our DIY Pick and Place machine USB Controller Board we needed to rewrite the controller software to drive the pick and place machine. The new Pick and Place software is written in C# and we […]
Sick of Beige basic case v1 (DP8049) back in stock
Sick Of Beige basic case v1 (DP8049) is back in stock at Seeed Studio. A clear laser-cut acrylic project case kit that fits DP8049 golden-rectangle PCBs (80mmx49mm). Sick of Beige v1 DP8049 project case is available at Seeed for $3.
Mailbox wireless alert project
If you are waiting for some electronic parts to be delivered the wait can be agony. It is especially painful when you learn your parts which you desperately need have been sitting in your mailbox for most of the day because the mailman came early… This problem is solved by this Mailbox Wireless Alert Project. Re-purposing […]
High altitude balloon electronics
Erdabyz writes: I’m part of a students association and we’ve had a helium tank in our place since 2003 which is still almost full. None of the current members knew where it came from until recently (turned out that we had a RC blimp of some sort back in those days…). So some time ago a […]
Free 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: using external memory with PIC24F/24H/dsPIC33F devices
Here’s an app note from Microchip on Interfacing external memories using Parallel Master Port (PMP) module. This application note describes the methodology to use the Parallel Master Port (PMP) module to interface with external data memory; either external Flash or external RAM. This application note also lists the APIs and describes how to implement different […]
App note: microcontrollers and triacs easily connected
Here’s an application note from NXP on how to easily connect main triacs and microcontrollers. This application note describes the easy connection of NXP LPC microcontrollers and three – quadrant (Hi-Com) triacs to control any resistive or inductive load at mains voltage. A one-for-all control method is presented that uses an innovative, patented, current zero-crossing […]
OctoPROBER rev0 board update
Parker Dillmann posted an update on his OctoPROBER board an 8 channel K-type thermocouple temperature logger, we wrote about it previously: I was having an issue with the FT230X being active while the 3.3V rails being turned off. The FT230X would backfeed voltage down the TXRX lines into the propeller which would power the 3.3V rail to ~2.7V causing […]
ATX Breakout Board V1.1 Acrylic case back in stock
The ATX Breakout Board v1.1 Sick of Beige case is back in stock at Seeed Studio. This case is designed to be simple, cheap, and easy to assemble. The ATX Breakout Board is sandwiched between two laser-cut acrylic sheets, and the whole assembly is held together with aluminum screws and standoffs. This is a minor […]
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 […]
Week in (p)review February 07, 2014
Here’s a summary of major developments over the last week. Free PCB Friday is coming up soon. Shenzhen workshop April 3-5, 2014 Free PCB Store restock: Prototype Bus Pirate probe cables N1KSN Iambic Keyer free PCB build Latest ‘New Year’ release of AnalysIR with full support for USB IR Toy Check out Tom’s 1-3 I2C […]
Temperature Shield for BBA3, part II
Kevin Rye posted an update on his Temperature Shield project we covered previously: It’s amazing how close I came to matching my 3D model! It’s just like I imagined it. I had already loaded my sketch before assembling it, so it was just a matter of crossing my fingers and plugging it in. Boom! It works like a […]
Fluke 196B Handheld ScopeMeter repair
Teardown and repair of a Fluke 196B Handheld ScopeMeter: In this episode Shahriar goes through the teardown and repair process of a Fluke 196B Handheld ScopeMeter. This unit, which has been purchased as a “dead” unit from eBay, is examined for faults. During the teardown, various PCB components, architecture and design is presented. The performance […]
Si4707 weather radio
Charles has been working on a Si4707 weather band radio project: Right now on the bench the PIC powers up, resets and powers up the radio, then tunes the radio via I2C to 162.55MHz. It finishes up by reading back the status and then dumps the Tuned Frequency and RSSI ( Received Signal Strength Indicator ) […]
N1KSN Iambic Keyer free PCB build
Marcello posted picture of his free Iambic Keyer PCB build, a guest PCB from Andy Palm/N1KSN If you build a free PCB we’ll send you another one! Blog about it, post a picture on Flicker, whatever – we’ll send you a coupon code for the free PCB drawer.
SSD1306 and Python with the BeagleBone Black
Ethan Zonca of Protofusion writes: The SSD1306 is an OLED display made with SPI and I2C interfaces. With a simple Python library I adapted (a modified version of py-gaugette), it is easy to render text, images (from bitmaps of pretty much any format), progress bars, etc. This guide is a bit on the long side, […]
Strobe guitar tuner r2
Neil has been working on a strobe guitar tuner project: I’ve learned a bunch about making circuit boards at work recently, so I decided to re-do the ol’ strobe guitar tuner project from 3 or 4 years ago. The original still works… sort of. I have to power it from a 3x AA battery holder that’s clipped […]
GPS for graphing calculators
Kerm Martian from Cemetech has documented a GPS for graphing calculators project build: Graphing calculators are nothing less than powerful pocket computers, capable of doing many of the same things as smartphones, desktops, and laptops. Given that they have reasonably fast processors, a display, memory, and ports to interface with the outside world, I set out […]