Posts Tagged ‘electronics’

NERP Tonight — A Tor Relay Demo, and a Sketchy Update

NERP Tonight — A Tor Relay Demo, and a Sketchy Update
NERP is not exclusively Raspberry Pi, the small computer
and embedded systems 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.

Drew has put together a Tor relay using (what else) a
BeagleBone Black.
(https://www.torproject.org/index.html.en) Tonight at NERP,
he’ll show us how it’s done.
From the Tor site:
/*
Why Anonymity Matters: Tor protects you by bouncing your
communications around a distributed network of relays run
by volunteers all around the world: it prevents somebody
watching your Internet connection from learning what sites
you visit, and it prevents the sites you visit from
learning your physical location.
*/
Use of Tor is often a sensitive discussion topic. In the
culture in which we live, there is no universal consensus
on where an individual’s right to privacy from governmental
and corporate interests ends and the larger interests of
security and commerce begin.

Tor is a tool that aims to provide user and location
anonymity on the Web. Anonymity can foster good, bad, or
indifferent ideologies and behaviors. In some contexts
anonymity can even be seen a sort of power similar to that
of a firearm. There are those who would question “a priori”
why a person would insist on total privacy unless they had
something to hide. From this perspective, using a privacy
tool is in itself suspicious. Others feel that privacy is a
basic need of human individuals, and therefore an
inalienable right. At the end of the day, technology itself
isn’t human, isn’t alive, and can’t think or feel; it’s
totally indifferent.

In tonight’s presentation we will try to stay focused on
the technology behind Tor. It’s counter intuitive to me at
least, how anonymizing technology is practically possible.
How it’s done will be an interesting study in some
non-obvious applications of low-level network programming.

Also tonight, I’ll be giving another update on development
of “Sketchy”, the network controlled servo-powered
Etch-a-Sketch.

Find NERP and Pumping Station:One at
www.meetup.com/NERP-Not-Exclusively-Raspberry-Pi/
and

http://pumpingstationone.org/

Doors open at 6:30pm. The next meeting is September
1st, 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

01

09 2014

NERP Tonight — NVIDIA’s CUDA: 192 Parallel Procesors

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.

Tonight at NERP, Sevin Straus will give an introduction to NVIDIA’s CUDA architecture. CUDA uses a cpu to farm out pieces of a task to the parallel processors in a video graphics chip (GPU). [more below]

NVIDIA's CUDA , NVIDIA.com

[img: large-video-dynamic-parallelism-2-en.jpg nvidia.com]

Nvidia wants lots of developers to know about CUDA. To that end, they have put together a complete development environment. In the best of all worlds, the environment should be usable on Linux after simply running “install.sh”. It’s never really that simple. Sevin has put together a working develpment system targeting the Jeston development board. Tonight he’ll show us how he did it and some of the included demos.

A sense of what CUDA is about would include these thoughts collected from various parts of the CUDA website:

CUDA® is a parallel computing platform and programming model invented by NVIDIA. It enables dramatic increases in computing performance by harnessing the power of the graphics processing unit (GPU). A GPU consists of thousands of smaller, more efficient cores designed for handling multiple tasks simultaneously.

GPU-accelerated computing is the use of a graphics processing unit (GPU) together with a CPU to accelerate the compute-intensive portions of tan application to the GPU, while the remainder of the code still runs on the CPU. From a user’s perspective, applications simply run significantly faster.

- See more at: http://www.nvidia.com/object/what-is-gpu-computing.html#sthash.hSegwmwk.dpuf

Find NERP and Pumping Station:One
at http://www.meetup.com/NERP-Not-Exclusively-Raspberry-Pi/
and http://pumpingstationone.org/
Doors open at 6:30pm. The next meeting is August 18th, 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

 

18

08 2014

NERP Tonite: The New Raspberry Pi B+, and The BeagleBone eQEP

NERP is Not Exclusively Raspberry Pi, the small computer and embedded systems 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.

Tonight at NERP, Craig LeMoyne will introduce the new Raspberry Pi Model B+: the new and improved version of the highly successful Model B. We will have a side by side comparison with the Model B and highlight the changes.

Servo motors are computer controllable motors that do pretty much the same thing as stepping motors. From a systems perspective they have nothing else in common. Servos use feedback to adjust the motor’s position and velocity. The difference between the target speed (or position) and the measured speed (or position) is called error. Without error, the motor has no reason to move. The type of sensor usually used to detect a motor’s position is called a quadrature encoder. Although servo systems can give better performance than steppers in some situations, servos are more complex and more expensive than steppers. Part of the complexity is reading and making sense of the encoder. Adafruit has posted a video in which Drew Fustini has a good job of introducing some techniques for accessing the special eQEP quadrature decoder module in the BeagleBone Black.

https://www.adafruit.com/blog/2014/07/15/how-to-read-the-position-of-a-rotary-encoder-connected-to-a-beagleboneblack-txinstruments-beagleboardorg/

A PS:One member (me) has a project that aims to use the BBB’s eQEP to control an Etch-a-Sketch. Tonight I’ll show some of the technology that’s involved and progress on assembling the system.

Find NERP and Pumping Station:One at

NERP – Not Exclusively Raspberry Pi

Chicago, IL
246 members

NERP is Not Exclusively Raspberry Pi, the small computer and embedded systems interest group at Pumping Station One in Chicago. (Chicago’s oldest and finest hackerspace.) NERP…

Next Meetup

Bring questions, demos, personal research, etc. to share.

Monday, Jul 21, 2014, 7:00 PM
7 Attending

Check out this Meetup Group →

and http://pumpingstationone.org/

Doors open at 6:30pm. The next meeting is July 21st, 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, BeagleBone, Element14, Pumping Station One

 

21

07 2014

NERP Tonite: Pingo means “pin, go!”

NERP is Not Exclusively Raspberry Pi, the small computer and
embedded systems 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.

Luciano Ramalho is a member of Garoa Hacker Clube in Sao Paulo,
Brazil (http://hackerspaces.org/wiki/Garoa_Hacker_Clube).
Tonight at NERP, Luciano will tell us about the Pingo
project in progress at Garoa HC
(http://www.pingo.io/docs/intro.html). Pingo aims to make
interconnecting small controllers of all sorts easy and
transparent, so that they can use each other’s peripherals. An
example use case would be using Python on a Beagle (or similar)
to effectively “program” one or more attached Arduinos.

From the website:
“Pingo provides a uniform API to program devices like the
Raspberry Pi, BeagleBone Black, pcDuino etc. just like the
Python DBAPI provides an uniform API for database programming in
Python.

The API is object-oriented but easy to use: a board is an
instance of a Board subclass. Every board has a dictionary
called pins which lists all GPIO pins on the board. Each pin is
an instance of a Pin subclass with attributes that you can
inspect to learn about its capabilities.”

Find NERP and Pumping Station:One
at http://www.meetup.com/NERP-Not-Exclusively-Raspberry-Pi/
and http://pumpingstationone.org/
Doors open at 6:30pm. The next meeting is July 7th, 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, BeagleBone, Element14, Pumping Station One

07

07 2014

DC Circuits Class Notes

DC_circuits

Thanks to everyone who came and participated in the circuits class this past weekend.  There was a lot of material that was covered and there was no way to go through it all in exhausting detail.  So I’m making available a scanned PDF of the notes I wrote for the class.  Enjoy all the spelling errors, in addition to the one found above.  The edges might be cut-off in some areas, but it’s the best I can do:   DC_Circuits_SK

Also, Carl Karsten did the exhausting (and usually thankless) job of recording a video of the class.  It can be found here:

http://videos.pumpingstationone.org/video/32/basic-electronics-dc-circuits-class

The solution to the bonus question was never explicitly stated in the video, so here it is:

bonus_solution

 

 

05

07 2014

Basic Electronics – DC Circuits Class – Sunday June 29th @ 2pm

1000px-Thevenin_Norton_conversion.svg

Well, I finally got around to finishing the curriculum for a beginning Electronics class.  This class will cover a lot of the fundamentals that should be known when designing any type of electronic circuit.  DC circuits will be covered here, so no frequency dependent (AC) topics will be touched.  Hopefully in the future, I’ll have time to eventually write a followup Intermediate Electronics class that will cover AC circuits.

It will be broken up into two parts, a lecture-ish part with lots of fun whiteboard time and a lab (hands-on) portion:

Lecture Topics:

  1. Electricity, conductors, and insulators
  2. Ohm’s Law
  3. KVL & KCL: Series and Parallel circuits
  4. Voltage Dividers
  5. Traditional Circuit Analysis: Mesh Currents & Node Voltage
  6. Better Analysis Tools: Superposition & Thevenin’s Theorem
  7. Silicon Diodes and LEDs

Lab Topics:

  1. DC Circuit Simulation with LTspice (the best analysis tool)
  2. Learn how to use solderless breadboards
  3. Build simple circuits using resistors and LEDs

I will be giving away one small electronics “starter kit” consisting of a solderless breadboard, bags of resistors and capacitors, a bunch of jumper wires, and a digital multimeter.  I’ll most likely dish this kit out by asking a bonus question and giving it away to the first person with the correct answer.  Anyway, hope to see you there!

The Details:

  • Who: Anyone who knows basic Algebra (Open to the Public)
  • When: Sunday, June 29th – 2:00pm to 4:00pm…..or 5pm or 6pm or however long you wanna stay and learn
  • Where: 3519 N. Elston – 2nd Floor in the Electronics Lab
  • Cost: FREE

 

26

06 2014

NERP June 23rd – BeagleBoard Project co-founder Jason Kridner

BeagleBoardCompliantLowRes

NERP June 23rd – BeagleBoard Project co-founder Jason Kridner

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.

Jason Kridner, BeagleBoard project co-founder, community manager, and software cat herder will speak at NERP on June 23. His topics will be “JavaScript on BeagleBone” and “Real-time programming with BeagleBone PRUs”. As part of his job at Texas Instruments, Jason provides support and development of the BeagleBoard.org project. He is also a member of hackerspace i3 Detroit.

The BeagleBone Black is the most recent in a series of single board Linux computers created by the folks behind BeagleBone.org http://beaglebone.org. The BeagleBone is designed for educators, designers, makers, and hackers. The BoneScript language, based on JavaScript, reaches out to Web software developers who want to get out of the box. Being a Linux (plus Android and others) computer, the BBB natively runs Python, C++, and the usual suspects. There is also a growing ecosystem of hardware add-on “capes” that shield the user from the complexity of developing interface devices.

Some quick specs on the BeagleBone Black rev C : Technology: Texas Instruments Sitara® 32-bit ARM core cpu @ 1GHz, 512MB SDRAM, accelerated HDMI, Ethernet, USB, 69 (max) GPIO, and a host of i/o peripherals directly accessible from onboard headers. Dim 3.4”x2.1”, weight 1.4 oz., Debian Linux pre-installed, Price $55. Availability: everywhere. Element14 is a good place to look http://www.element14.com/community/docs/DOC-54121?ICID=knode-beagleboneblack-space/

PLEASE NOTE: For this special NERP, we will keep introductions short and start promptly at 7pm. Please use the meetup (below) to confirm your attendance!

Find NERP and Pumping Station:One
at http://www.meetup.com/NERP-Not-Exclusively-Raspberry-Pi/
and http://pumpingstationone.org/

Doors open at 6:30pm. The next meeting is June 23rd, 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, BeagleBone, Element14, Pumping Station One

19

06 2014

U Can Has BeagleBone Black (but only one).

 BeagleBoard_Boris_Tux

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.

The BeagleBone Black is a small single board computer in the same vein as the Raspberry Pi. The two boards are similar in appearance and composition but different in style. Both boards are based on 32-bit ARM-based processors. The Beagle’s is more recent and faster. The RPi is designed as a teaching platform that happens to have very nice graphics and video, but not much i/o. The Beagle’s graphics are wanting, but it has tons of i/o on the board. The Pi is more polished than the Beagle, in that what’s supposed to work usually does. The Beagle is more suited (for the moment) to dirty-fingernails hackers who enjoy hardware for its own sake.

One thing the two boards have in common is that their first manufacturing runs sold out quickly. It’s been weeks since there were any BeagleBone Blacks to be had for sale. (People have been hoarding them as OEM parts for their startup projects.) In the last few days, BeagleBone Blacks have been trickling out of CircuitCo’s production line. There are about 47,600 boards in the pipe, but you’re allowed to buy only one. http://specialcomp.com/beaglebone/ has them now for $45.00 each.

It’s time to give the BeagleBone Black another look at NERP.

Tonight we’ll go over some of the getting started routine, and have a peek under the hood of the Bonescript, the Beagle’s Arduino-like programming environment built on Node.js.

It’s time to give the BeagleBone Black another look at NERP.

Tonight we’ll go over some of the getting started routine, and have a peek under the hood of the Bonescript, the Beagle’s Arduino-like programming environment built on Node.js.

Find NERP and Pumping Station:One
at http://www.meetup.com/NERP-Not-Exclusively-Raspberry-Pi/
and http://pumpingstationone.org/
Doors open at 6:30pm. The next meeting is April28th, 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

 

 

28

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.
radio-1
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
at http://www.meetup.com/NERP-Not-Exclusively-Raspberry-Pi/
and http://pumpingstationone.org/
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

31

03 2014

NERP: Playing with the BeagleBone Black

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.

Tonight at NERP, we’ll be playing with the BeagleBone Black. We’ll compare the look and feel of an original Angstrom Linux install with a fresh Debian Wheesy install. Beagles and their kin are complicated little devices, and there’s lots to see and try out (and fix) for a newbie user. We’ll sniff around the Beagle install and hardware just to pick up some landmarks for future projects and ideas.

 

Find NERP and Pumping Station:One
at http://www.meetup.com/NERP-Not-Exclusively-Raspberry-Pi/
and http://pumpingstationone.org/
Doors open at 6:30pm. The next meeting is March 17th, 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

 

17

03 2014