Posts Tagged ‘electronics’

NERP Tonight — Report on OHS #5 in Rome -and- An FPGA Cape for the BBB

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’s NERP will be brought to you by Drew Fustini, PS:One’s maven of all things Open Source. Drew recently got an FPGA cape for the BeagleBone. The cape is called a LOGI (http://valentfx.com/logi-bone/). He’ll show us what he learned as he road-tested the development tools and the cape.

Also tonight NERP will get a brief overview of embedded computing topics from the 5th Open Hardware Summit (OHS), held this year in Rome, Italy. Drew went so we didn’t have to.

I’m out this week, so thanks much to Drew for hosting the meeting.
-Ed

Find NERP and Pumping Station:One at

NERP – Not Exclusively Raspberry Pi

Chicago, IL
271 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, Oct 27, 2014, 7:00 PM
9 Attending

Check out this Meetup Group →

and

http://pumpingstationone.org/

Doors open at 6:30pm. The next meeting is October
27th, 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

27

10 2014

NERP Tonight — JTAG on the Brain

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.

Electric_hair_curler / Brain-Machine Interface

Joao (“Gamblit” on the PS:One mailing list) will give an introduction to JTAG at NERP on Monday. JTAG is an important tool for embedded developers, manufacturers, and hardware hackers who do reverse engineering. The JTAG interface is included in all but the smallest processors. For use in degugging, JTAG provides real-time read/write access to a chip’s cpu, i/o systems, ram, and mass storage. It gives a user live access points inside a running cpu from which they can take over its brain, or just burn a fresh rom.

Physically, JTAG consists of a small set of pins on a microprocessor, a hardware interface device, a cable connected to a host computer, and a (not physical) protocol. JTAG is most generally useful for programming the flash in embedded controllers. That much is simple. The rest, of course is software.

Joao’s tools and target will include:

– Linux Host (Fedora VM)
– GDB (GNU Debugger) and DDD as debuggers
– No IDE (VIM and direct GCC if I need it)
– Olimex USB JTAG and TIAO USB generic interface
– Olimex Atmega128 board (Atmel Atmega128 MCU)

Joao says:
I’ll be talking about flash programming and debugging software running on a
micro-controller. I’ll also be showing that it can read and set
micro-controller pins but not getting into depth about how that actually
works, as that would need some additional low-level explanation. Depending
on feedback and available time I might explore a bit of it.
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 October
13th, 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

12

10 2014

NERP Tonight: A Simple Wireless Link for Serial Data

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.

Amongst the Maker community ZigBee® is usually thought of alongside the XBee® modules from Digi Corporation. The little blue irregular-hexagon shaped boards mean “wireless data” to a lot of folks. XBee is in fact the name of a family of wireless data modules that share the same form factor and blue color. The family includes ZigBee modules, DigiMesh modules, WiFi modules, and IEEE802.15.4 radios. Depending on the model, the data radios can do point-to-point, peer-to-peer, star, and mesh networks.

If you’d like to play around with wireless data a good place to start is replacing a serial cable with an XBee Series 1 module. There are two power levels to choose from: a 1mW module that can work to a distance of 300ft, and a 60 mW module that can work to a distance of one mile (in perfect conditions).

The Series 1 modules are usually used as IEEE 802.15.4 data radios. ZigBee and several other protocols are built on top of 802.15.4.The 802.15.4 spec provides the physical and MAC layers to serve higer level protocols. It’s a just enough support to get bytes sent from A to B. One nice thing about working close to the metal is that, once the hardware is set up, it’s fairly easy to push bytes around. You can even make up your own simple ad-hoc protocols if needed.

Tonight at NERP, I’ll show how to set up a wireless data link between two devices that can communicate at 300 to 115200 baud. I’ll show XBee XPB24-AWI-001’s moving serial data, and how to set up and test the modules using the X-CTU software from Digi.

As a side-note, the Internet of Things is creating a demand for better and cheaper wireless data connections. It is common for the Things to speak a local protocol that is propietary or unique to their class of device and for the relevant parts of the machine to machine dialog to be passed upstream through a server or bridge.

ZigBee® is a trademark of the ZigBee Consortium

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 September 29th, 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

29

09 2014

SPICE it up – Circuit Simulation using LTspice

spice_it_up

Probably the most neglected, yet most useful, tool for circuit designers is SPICE.  SPICE gives you the luxury of simulating circuits to predict the results prior to building a physical circuit.  Being able to change resistor values or transistor configurations within a couple mouse clicks and a few keyboard presses, is a very powerful and time/money saving feature.  As such, it is also very useful in troubleshooting previously built circuits to find solutions to lingering design problems.

SPICE (Simulation Program with Integrated Circuit Emphasis) is open-source software released under the “BSD license”.  Several companies produce their own version of SPICE, such as TINA from DesignSoft or PSpice from Cadence.  However, the fastest and most user friendly implementation is LTspice.  LTspice is provided by Linear Technology and is completely free to use without restriction.  It is the same software that is used internally at Linear Tech to develop and test their line of analog/linear semiconductor ICs.  It was written by Mike Engelhardt, who periodically goes on tour teaching classes and answering detailed questions for his own software.

I’ll be holding a class to introduce the basics of using LTspice.  LTspice was originally written for Windows and was recently ported to Mac OS X.  The Windows version is capable of being run on Linux through Wine, but it obviously doesn’t run as well as on a native Windows machine.  I’ll be teaching with the Windows version, since I am the most familiar with it.  The Mac version has a slightly different user interface, but it shouldn’t be too difficult to keep up.  Here are the topics I’ll be covering:

  1. Placing & Wiring Up Components
  2. The Most Basic Simulation: DC Operating Point
  3. Labels and “Net” Names
  4. Finding Frequency Response: AC Sweep
  5. Using the Plot Window
  6. The Real Deal: Time-Domain Simulation (Transient Analysis)
  7. Piece-Wise Linear (PWL) Sources
  8. Using SPICE “Directives”
  9. Working with Semiconductors
  10. Linear Tech’s IC Models and Test Jigs
  11. Importing 3rd Party Models & Sub-circuits

 

The Details:

  • Who: Anyone who wants to learn LTspice (Open to the Public).  Some circuit knowledge is required.
  • When: Sunday, September 28th – 2:00pm to 4:00pm
  • Where: 3519 N. Elston – 2nd Floor in the Electronics Lab
  • Cost: FREE

 

18

09 2014

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