Intro to Programmable Logic & FPGAs – April 27


I’ve been bugged to death lately about doing another FPGA intro class…and after a full year, it’s finally here.  We’ll be going over some theory & concepts first before we hit the real stuff.  Familiarity with digital logic circuits is highly recommended, but you will still learn something regardless.  A basic overview of what will be covered:

  1. Combinational Logic – Basic Logic Gates
  2. Sequential Logic – Flips Flops
  3. CPLD – Complex Programmable Logic Device
  4. FPGA – Field Programmable Gate Array
  5. Nintendo DS ReView – An Example of What FPGAs Can Do
  6. Xilinx ISE & Verilog – Synthesizing the First Project
  7. Using Clocks – Blink that LED!
  8. State Machines – Alternate between blinking different LEDs!
  9. Video Example – Making an 8-bit VGA controller

I’ll be using the Elbert FPGA development board for most of the examples we’ll be doing.  Having the board is not required to attend.  I will bring a disc with the software tools in case anyone would like to install them.  We will be using Verilog as the HDL (hardware description language) in this class, since that is what I am familiar with.

The Details:

  • Who: Anyone (Open to the Public)
  • When: Sunday, April 27th – 2:00pm to 4:00pm….but we can chill until 5:00pm.
  • Where: 3519 N. Elston – 2nd Floor in the Electronics Lab
  • Cost: FREE



04 2014

Tonight at NERP: Movement detection with Motion

NERP is not exclusively Raspberry Pi, the small computer interest group at Pumping Station:One in Chicago. NERP meets every other Monday at 7pm at Pumping Station:One, 3519 N. Elston Ave. in Chicago.

To do make a security-cam type device with a Raspberry Pi or a Beagle Bone, the software must run on Linux. There are several computer vision based motion detection applications available for Linux. The OpenCV framework can be used to build Computer Vision applications that do heavy mathematical operation on streams in real time. (It also can be used to draw colored shapes on your screen.) If the versatility of OpenCV isn’t needed for a simple camera app there are a number of movement detection and recording applications to choose from. One of the oldest is Motion. Motion is command line driven. It produces its output as a browser viewable video images, stills, and a few control output options. In contrast with writing applications using OpenCV, it’s very simple to unbox and and fire up Motion. With its simplicity comes limited versatility, but it might be suited to your CV needs.

Find NERP and Pumping Station:One
Doors open at 6:30pm. The next meeting is March 3rd, 2014. NERP is free and open to the public.
Ed Bennett ed @ kinetics and electronics com
Tags: electronics, embedded, NERP, Open Source, raspberry pi, hackerspace, Beagle Bone, Element14, Pumping Station One


04 2014

Mini Maker Faire in Chicago at Schurz High School – May 3

Reserve your spot to the third annual Chicago Northside Mini Maker Faire! Tickets are FREE to the public, but by reserving early you guarantee your spot. Now you can e-sign the media release on Eventbrite and skip the line! As always, your generous donations allow those who cannot otherwise afford Maker Faire to attend for free. Recommended donations are $10/adult, and $5/child under 12.

Pumping Station: One will hopefully be there with a table. Come visit us!




04 2014

A Good Egg or, What Happens When Hackers Celebrate Pysanky Day

Okay, so first of all, Pysanky Day is a very special day celebrating the thousands-of-years-old art of Ukrainian egg decorating (a “pysanka” is one such egg, “pysanky” is multiples of them).  Now, there’s not an actual Pysanky Day; folks decorate the eggs traditionally around Easter time.  In my household, however, we celebrate several different holidays around Spring:  Passover, Easter, and Ostara.  Each year we decorate eggs and it’s grown from just Paas dyes to pysanky.

When I asked one of my fellow hackers if they’d like to learn the art, they got totally excited about using the Egg Bot.

The what?

The Egg Bot!

Of course, there’s a bot for eggs.  Why?  Because Hackerspace.

And thus, Pysanky Day was born.


A celebration of the ancient:  the plain egg is drawn on with melted beeswax using a tool called a “kistka.”  Based on technology that’s about four thousand years old, it just consists of a stick or dowel with a hole drilled in one end, into which is inserted a metal funnel.  The funnel is held in place with copper wire.

After heating the tip of the kistka in a candle flame, a small amount of wax is scooped into the fat part of the funnel.  It takes some practice to get the wax to flow smoothly without making drops of wax on the egg.


One of my favorite designs, this is from one of the series of five Ukrainian Design Books available from the Ukrainian Gift Shop in Roseville, Minnesota. Part of the design was done with a traditional kistka, and part was done with an electric kistka.

In principle, the electric one works the same as the manual one; I like it better because the flow of wax is much more even.


We got to playing with the Egg Bot, which brings us up to present day technology. Using a pen, it writes on the egg. The writing is completely programmable.


And finally, in true hacker style, we used the 3-D printer to print an egg holder in the shape of a bunny rabbit. One of our members, walking through the space toward the end of Pysanky Day, commented, “Oh! Rabbit Pants!”

Yup. Hackerspace.


All egg images used by permission, copyright: CC-BY-SA Everett C. Wilson (

Image of the Egg Bot from the Egg Bot site, (


04 2014

Digital Game Night, 4.5.14

This Saturday it’s time to bring the pain…the childhood pain we all experienced playing video games never to see their ending. It’s time to pick up the controllers, yell at a screen, and speedrun through the night spanning Nintendo, Super Nintendo, Sega Genesis, and Xbox 360 arcade games. The whole night starts with a round of You Don’t Know Jack where the winner gets to decide the first console/game of the night (from there on group votes will decide.)

This event is available to all members of PS:One and begins at 7pm in electronics. See you there!


04 2014

CNC Build Club: 32-Bit Controllers for CNC








32-Bit CNC Controllers are making a strong showing lately.  I have several that I can show, compare and trace to roots of at this week’s CNC Build Club (Thursday 4/3/2014 @ 7:00pm)


The TinyG has been around for a few years.  It can be purchased here.  It started as an XMega firmware/hardware project, that has been morphing into a cross process solution.  The basic TinyG is the XMega on their own hardware with 4 on board stepper drivers. It has very advanced motion control algorithms, including constant jerk.   The project is open source and on Github.




The second, but less popular format, the TinyG2, is running on a standard Arduino Due with a driver shield.  Here is it shown with a gShield.








The other popular 32 Bit CNC controller is he Smoothie project.  After about a year of prototypes they did a popular Kickstarter.  The Kickstarter is over and delivered and you can buy the hardware.  The project is open source.  Most of the motion control is based on a port of GRBL.  The project details are here and the GitHub repo is here.  The project supports 3D printers, laser (cutting only) and CNC routers.


Azteeg X5 Mini

This is the Azteeg x5 mini.  It is a another hardware solution for Smoothieware.  It is available for sale here.






04 2014

Tonight at NERP: Drew demonstrates Software Defined Radio

NERP is not exclusively Raspberry Pi, the small computer interest group at Pumping Station:One in Chicago. NERP meets every other Monday at 7pm at Pumping Station:One, 3519 N. Elston Ave. in Chicago.
Software Defined Radio is a set of techniques for generating modulated RF waveforms in a transmitter, and demodulating the waveforms in a receiver. In traditional radio transmitters, the broadcast carrier waveform is generated in resonating analog circuits. The carrier is subsequently modulated in a specific way to encode information onto the carrier waveform. There are several distinct methods for doing the encoding and modulation. At the receiver the modulated carrier is received, amplified, and decoded to extract the transmitted information. Analog circuits are bulky. They could never fit in a cell phone, for instance. Worse, a specific analog circuit can operate over a very narrow range of frequencies (a “band”) and the modulation/demodulation method is inflexibly determined by the circuit topology.

Software defined radio allows the radio hardware to generate the physical carrier frequency and modulation format by algorithmic synthesis. Until recently, open (or open-ish) hardware capable of doing the waveform generation math in real time was not available at an affordable price. This has changed. Tonight at NERP, Drew Fustini will demo Aafruit’s “Software Defined Radio USB Stick” receiver. From the product description on the Adafruit site, the little radio does some absolutely amazing things. Software is eating the world, and radio is on the menu.

Find NERP and Pumping Station:One
Doors open at 6:30pm. The next meeting is March 3rd, 2014. NERP is free and open to the public.
Ed Bennett ed @ kinetics and electronics com
Tags: electronics, embedded, NERP, Open Source, raspberry pi, hackerspace, Beagle Bone, Element14, Software defined Radio Pumping Station One


03 2014

Special Circuit Bending eSymposium this Sunday

Sunday, April 6

12 PM – 4 PM, FREE

Hacking upstairs in Electronics, open jam session downstairs in the Lounge.

Hosted by Patrick McCarthy of the circuit-bending act Roth Mobot.

Bring something to hack, something to drink, and whatever tools you think you’ll need. PS:One has an excellent assortment of tools but they are finite. Components are available, but please donate some cash to help cover whatever you use.

Radio WFMT will be on location recording a documentary about the eSymposium.


03 2014

International Tabletop Day 2014

International tabletop day

International Tabletop Day

Want to hang out with a group of fun geeky people at a Hackerspace and play some awesome games? How about homemade snacks and homebrew beer? Still not awesome enough for you? Well, how about we hack an Xbox Kinect and scan you, then 3D print a custom game piece with your face on it, or make custom game counters on a laser cutter?

Come on by Pumping Station: One, Chicago’s biggest Hackerspace, on April 5th and have some fun and maybe even learn a few skills! Bring your favorite games, or if you want some supreme geeky-points, bring a game you designed and play-test it with us [we can even discuss how to spruce-up your game with lasercut or 3D printed pieces, hint-hint]!

This event is public, so bring your family, friends, or just awesome gamers you know and wanna hang out with! If you want to take part in making the 3D printed game pieces, or laser cutting custom counters, we do ask for a minimum of $1 suggested donation to cover materials. If you want to see this stuff continue into the future, please donate more! Proceeds will go to Pumping Station: One’s donation box.


03 2014

CNC Steampunk Harp – Getting Your Guts in a Knot – Part 3


Elizabeth and Ryan with a fully strung harp

Elizabeth and Ryan with a fully strung harp

[See Part 2]

At long last, the CNC Steampunk Harp that Elizabeth and I have been building is, at least functionally, finished! In previous posts, I documented the process of routing pockets in the side of the harp using PS:One’s CNC router, and our road trip to Sector67 in Madison, WI to use their seriously awesome laser cutter. This completed the work on all wooden parts of the harp, and so I could finally assemble it.

First, I had to glue the stiffener boards to the back of the sound board and used the drill press to make holes for the 33 strings. Gluing the sound board to the harp body required a lot of fast work: driving nails to hold the sound board in place, flipping it over and trying to wipe out the dripping glue while only having access to the inside via small holes, flipping it over to drive more nails, rinse, lather, repeat… all the while, the glue is starting to set. Then I glued the trim strips in place that covered all the nails. After that glue dried, I used a 1/4″ roundover bit on a router to clean up the sides of the sound box, and… oops! To my horror, I realized I forgot a step in the directions that said I was supposed to use extra nails to reinforce the area where the sound board joins the base near the pillar. Seeing as the harp has over 1000 lbs tension on the sound board and I really don’t want it pulling itself apart, I used the pneumatic nailer to shoot brads through the lower front trim strip. Then I needed to use wood putty to cover the brads. Oh, and did I mention that the angle of the nail gun wasn’t quite right and the brads poked through the bottom? So I had to bend them over with a nail set and cover those holes as well with wood putty. You live, you learn….

Read the rest of this entry →


03 2014