Command line LCD Arduino interface

Joseph Swanson from swantron likes working with the command line. He also likes working with the Arduino. So he came up with this simple project which takes the results of his command line entries and directs them over the Linux box’s USB output to the Arduino. The Arduino then displays the data on an attached parallel LCD. The sketch code is included for this easily implemented and useful technique.

(The wonky character wrapping he notes is probably due to the way the HD44780 based 4×20 LCDs pair the display lines, which should be correctable with a code mod.)

App Note: Analog switch multiplexes SFP modules

rsdio writes: There is probably a way to implement this circuit with any analog mux instead of the Maxim part…

Analog Switch Multiplexes SFP Modules

To avoid multiple I²C bus masters in a telecom or data-communications system with SFP modules, add an analog multiplexer (MAX4572) that directs the data line to the appropriate SFP module.

App Note: Isolated power using capacitors

rsdio tipped us to an app note on isolated power-supply circuits:

Wow! It’s quite interesting to see how to substitute capacitors for a transformer. Without digging deeper, though, it’s not clear whether voltage boost can be achieved.

An integrated H-bridge driver for isolated power-supply circuits (MAX256) usually drives the primary of a transformer, but it can also drive a pair of capacitors that substitute for the transformer in providing isolation and power transfer.

Thanks rsdio!

Free VideoOverlayShield v.10.02 PCB via Facebook comments

Every Friday we give away some extra PCBs via Facebook. The first few people who comment on this at Facebook get a free PCB. More PCBs via Twitter on Tuesday and the blog every Sunday.

This week we have a guest free PCB, two VideoOverlayShield v.10.02 boards from Low Voltage Labs.  The Arduino compatible shield board overlays text on analog video, using the Maxim MAX7456 on-screen display chip. This board allows easy overlay of text onto an analog video signal, NTSC or PAL. Connect this board to your favorite Arduino processor board to get started. Eric gave us a couple of these boards at Maker Faire, and now you can grab one from the free PCB drawer. Also available for 9 bucks from the Low Voltage Labs store.

Don’t forget there’s free PCBs three times a every week:

  • Free PCB Sunday. The classic. Every week, right here on the blog
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs while you wait for the weekend

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Purdue senior design roundup 2011

Each year the Purdue seniors in electrical and computer engineering design and construct projects as part of their coursework. For your reading and viewing pleasure, here’s a descriptive summary of the projects produced by the 15 teams participating in the this spring’s ECE477 design roundup.

A summary of the rules which governed these design projects can be found on pages 3 and 4 of the course description document.

Via George and the other Purdue alums at NBitWonder.

Week in (p)review: May 27, 2011

Eric Pan (Seeed Studio) and Ian (me).

Facebook free PCB Friday is on the way. Don’t forget to share your current project in the comments or the forum.

Here’s a summary of major developments over the last week:

Coming this week:

  • An interview with Microchip’s PR driods about the new chipKIT Arduino-like board
  • Bus Blaster v2 restock is coming, more CoolRunner-II dev-boards too
  • Bus Pirate v3.5, a minor update, should be stocked soon
  • We’ll look as some new boards, and new revisions of existing projects
  • Debug IR Toy IR transmit problems
  • Hopefully a video blog
  • More updated release packages
  • Free PCB Sunday
  • Free PCBs via Twitter on Tuesday
  • Free PCBs via Facebook on Friday
  • Weekly roundup and preview every Friday

What are you hacking this week?

Practical MC13224 firmware extraction

Travis Goodspeed wrote this article on his blog detailing his extraction of firmware from the MC13224 that had been read protected. This is the same MCU used in the Defcon 18 badge and the Redwire Econotag.

He presents two methods. In one he decaps the SPI flash memory chip using nitric acid, then removes and repackages it. The second method involves accessing Pin 133 of the memory chip, when can be used to initiate a reset and process to provide access to the contents.

Single-sided, through-hole USB IR Toy v2

LisandroP made a  single-sided PCB version of the USB IR Toy v2:

I’ve recently built a single-sided, through-hole version of the USB IR Toy v2, using the schematic posted on the wiki for it without the pin breakout area…

Mine is 40x50mm using an USB-A connector and includes a USB pin header, VCC/GND/RX/TX header for serial communications and ICSP – had to dispense with the pin breakout area though.

gSchem and PCB formatted design files are posted.

Via the forum.

Saleae Logic 16 update

We went a bit overboard speculating about the new Saleae 16bit logic analyzer. After taking to designer Joe Garrison at Maker Faire though, it seems we weren’t that far from the mark.

The new Saleae does in fact have a Spartan FPGA to help get a flexible sample rate as high as 100MHz for 2 channels and complex triggering. Future updates may include RLE compression for even faster/more reliable logic capture.

Foosball table uses Arduino to put scores on web

The gang at SinnerSchrader have combined their love of foosball and their passion for digital solutions to make the world’s first digital foosball game. The project uses optical sensors to detect the scoring of goals. These sensors are read with the Arduino which sends it over WiFi to the server which then makes it available over the internet via mobile Webapp and on their agency foosball league’s webpage.

They promise that the source code will be published on their site very soon.

Via CrunchGear.

Atmel AVR Xplained dev boards


Atmel has announced their AVR Xplained series of dev boards.

Atmel AVR Xplained is a series small-sized and easy-to-use evaluation kits for 8- and 32-bit AVR microcontrollers. It consists of a series of low cost MCU boards for evaluation and demonstration of feature and capabilities of different AVR familie. Example projects and code drivers are provided in AVR Studio 5. Code functionality is easily added by pulling in additional drivers and libraries from the AVR Software Framework.

The AVR Xplained series also consists of a range of add-on boards that can be stacked on the MCU boards to create platforms for specific application development. A wide range of add-on boards is available, including, intertial pressure and temperature sensors, ZigBee RF, and Cryptographic authentication.

List price for MCU boards is around $30, with sensor modules between $25-54.

Details on features and availability are available from Atmel.

Arduino to Android IO on the cheap (aka Poor Man’s NFC)

Joe Desbonnet was looking for a cheap and easy way to transfer data from an Arduino to an Android device. The hack he devised requires only a 1-meter length of wire wound into a coil, a resistor and diode. He writes:

This is a little hack that allows very low bandwidth communications in one direction for practically no cost. It’s not practical for most applications, but I thought the idea was sufficiently interesting to explore. This article describes how to implement a very low bandwidth one way communication channel between an Arduino (or any other microcontroller) and an Android device using nothing more than about a meter of magnet wire, a resistor and diode. Links to a software sketch for the Arduino and the Android source code is included.

Cool and imaginative!

Thanks Joe! Via the contact form.

Microchip chipKIT giveaway and free shipping

Octal posted a free shipping coupon for Microchip’s new chipKIT 32bit Arduino-compatible platform. This is Microchip’s grab for some of the Arduino crowd action. They released an Arduino processing-based interface with sort of open compiler. Arduino sketches compile and run on the PIC chipKIT platform without any code changes.

FREE shipping coupon for the new chipKIT platform on MicrochipDIRECT, Enter code CHIPKIT; offer runs through June 30th, 2011.

We’re going to chat with someone at Microchip about the new platform, and we have freebies to give away. You can submit questions in the forum, we’ll give chipKITs to our favorite questioners.

Thanks octal! Via the forum.

Gmote turns Android into a remote control

Michael writes:

Gmote turns Android into a remote control for a computer, allowing users to run movies and music at a distance. It supports all of the standard remote control features such as play, pause, rewind, volume controls etc. It also has a built-in file browser that lets you select what to play.

Source code is open so it maybe possible to expand it to other functions.

Via the contact form.

DIY inkjet printer

This quarter at the University of Washington a group of students (Patrick Hannan, Jared Knutzen, Joy Markham, & Myself – Nicholas C Lewis) produced some documentation on the development of a DIY inkjet printer.  This project is attracting a lot of attention and spawning some interesting ideas.  There are people talking about adapting it to print on spherical objects, direct etch resist PCBs, 3d powder printer projects, and printing color on plastic parts made with FDM printers.

The goal of this project was to develop a low cost, open source inkjet printer utilizing standard inkjet technology, for personal use. This project was partly in response to the fact that there are no DIY inkjet kits available. There was a kit available from Parallax parallax.com/dl/docs/prod/robo/InkjetKitDocs-v1.0.pdf. This kit is no longer made and the book amazon.com/Inkjet-Applications-Matt-Gilliland/dp/0972015930 that was written to use that kit is now out of print.

The documentation is available as a thing on Thingiverse, a photo album and a video.

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Web interactive LCD controlled by Arduino


Here’s a project by Everett Robinson which demonstrates how to use an Arduino, Ethernet shield, 2×16 LCD, a breadboard and 2K resistor to produce a web-controlled interactive LCD display. The Arduino generates a simple HTML web page showing the text currently displayed on the LCD, providing an input form to change the LCD text, resulting in a web based LCD scratchpad. The Arduino parses the HTML Header using some code adapted from Kevin Haw’s RoboSapien Server project.

You can view the source code here.