At The Corner of Ampere & Ohm In The Bronx (Yes, This Intersection Actually Exists!) @ Scouting NY.

According to the Parks Department, the land was donated to the city by Issac Leopold Rice, inventor and president of the Electric Storage Battery Company, and later the Electric Boat company and the Electric Vehicle company. Because of his background, the city chose to honor his donation with appropriately named streets.

How USB turned Intel’s Ajay Bhatt into rock star – CNN.com.

With computer technology advancing at an ever bewildering pace, it’s comforting to know that one little feature remains steadfastly future-proof and, more importantly, foolproof.

The USB (Universal Serial Bus) is as relevant today as it was when the 12 millimeter by 4.5 millimeter ports and cables first started appearing back in the late 1990s, providing users with a discreet and straightforward way of transferring data between a range of digital devices.

Today, more than 10 billion USB devices are believed to be in use around the world — a statistic that has secured its co-inventor, Ajay Bhatt, a permanent place in computing’s unofficial hall of fame.
“I was totally surprised by how it has impacted everybody. I mean, my name became a common name — at least at schools and in technical communities,” Bhatt said.

Creating a Glass Circuit Board via MAKE. Andrew writes -

I was inspired by CNLohr to create my own glass circuit board. I decided to create a 2D LED matrix because the layout is simple enough to fit onto a single sided board.

I decided to take a different approach than CNLohr took. Rather than adhering a layer of copper to the glass and etching out the traces, I used copper tape and glued each trace to the glass. Unfortunately this takes away the printed aspect of PCB manufacture but it allowed me to complete the project using parts that I found in a local craft store.

Here is a picture of the completed project.

This is a very quick video guide to working with custom PCB connectors. I recently had to make a custom connector for my Raspberry PI, which has a bank of male headers. I looked at a few different options and in the end I decided I would invest in a crimp tool to create my own custom cables. While the experiences are still fresh in my mind I decided I would make this video in case that it will be of benefit as an introductory guide to others who are trying to do the same sort of thing. The video will discuss regular ribbon cables, fixed length pre-crimped cables, and custom crimped cables. I will also give a guide to how to crimp 0.1″ male and female PCB interconnect cables and describe what a proper crimp connector should look like.

This video is part of materials on modules taught by Derek Molloy, School of Electronic Engineering at Dublin City University, Ireland: http://www.eeng.dcu.ie/~molloyd/.

OSH Park will be taking over BatchPCB operations.

Starting May 1st, OSH Park will be taking over BatchPCB operations, including order placement and customer service.

Wow! This is pretty interesting news OSH Park is a great service! The post sales “sale of” – acquisition price was not posted. Here’s a previous interview John & Phil did with Laen.

You’ll wanna pull up a really comfy chair before you dive into this one, but have you ever found yourself digging through Eagle’s 317,424 different canned footprints, hoping one is kinda, sorta, almost, maybe good enough for that new sensor you found on Digikey?  Shamelessly dig and despair no more!  … Our new mammoth guide on creating manufacturable footprints in Eagle is here to ween you off that nasty canned footprint habit, and get you firmly on the road to non-dependency!

How to build a DCF77 HID USB real-time clock (dcf77-hid-usb-rtc) for usage with Linux systems from Alexander Holler:

This page describes how you can use an Atmel ATmega32U4 (e.g. an Arduino Leonardo, Teensy or clone) and a DCF77 receiver to build a (hot-pluggable) HID USB real-time (radio) clock (I’ve named it dcf77-hid-usb-rtc), for usage with Linux systems.

Because it is a radio clock, it will always have the exact time, at least as long as it will receive a signal from the German DCF77 time code transmitter in Mainflingen. So it is perfectly usable as a reliable stratum 0 time source for your network (if a resolution of one second fits your needs). As this isn’t a scientific paper about accurate and reliable real-time clocks, I will not go further into the details of time keeping. As a first step you might read the Wikipedia article about NTP.

It’s my second project in a small series about hot-pluggable USB RTCs. I’ve described my first project here: How to build an USB real-time clock (usb-rtc). A third one might follow.

The overall cost for one of those thingies I’m describing here is about 25€, which isn’t really cheap. But I find it a valuable thingy because the result is a hot pluggable RTC, usable by almost any device which has USB. So it’s very likely you will use it for much longer than the computer you currently want to build or search it for….

Read more.

Now here are some wedding vows that the Adafruit crowd can get behind — soldering a project together that lights up to say “I DO” as a metaphor for the marriage contract. Fascinating! From Bill Porter’s blog:

When it came time for Mara and I to draft our wedding ceremony we pondered how we could incorporate an element from our theme. We had 4 days to go and only some vague ideas. Mara bought some wood letters to spell out ‘I Do’ and wanted to use them in the ceremony. We also joked about using a soldering iron during the ceremony; but how could we do it tastefully? Then it hit us, a common wedding ceremony know as the “Fishermen’s Knot” could be reworded for something a little more geeky. Yes, we really did solder some wires together in the middle of our wedding, with a Weller soldering iron Mara bought me for a past birthday no less. And you won’t believe what PCBs came in handy for the build…

Ok, this post will be short because this project was thrown together 4 days before the wedding and we didn’t have time to stop and document the steps. We were set to get married and still had a lot to do, as evident by the mini-maker space we created in my parents house (see below).

Mara bought the letters at a local hobby store. I sketched out a rough outline of evenly spaced LEDs and went to work creating the holes with a drill press. A coat of blank paint and then my best man Dan went to work soldering wires to all those LEDs. Next we had to figured out a way to control those LEDs. In a pleasant case of coincidence, the boards I hijacked to ask my bride to marry me 2 years ago were designed to control large numbers of LEDs. Yes, the boards that asked “Mara Will You Marry Me?” were used to run letters that said ‘I Do’ during our wedding ceremony.

Read more.

Analysis: Pricing Hike Post-Merger in Two Cases – Blog – Octopart.

Last week, Vishay announced that it’s acquiring MCB Industrie S.A, a manufacturer of specialty resistors. Acquisitions have been a key piece of Vishay’s strategy, so we took a look at its track record to see the effect on market pricing of the target company’s products. (We used Octopart’shistorical pricing data.)

Today would be the 115th birthday of Harold Stephen Black, who invented the negative-feedback amplifier in 1927. The story goes that Mr. Black was taking the ferry from New Jersey to New York City (where Bell Labs was then located), and while on the boat he was struck by the idea to use negative feedback to linearize an amplifier stage.

The idea of negative feedback is a powerful one, because it provides a means to construct amplifiers with precise gain characteristics from parts with less than ideal specs. This makes it easier to build circuits with interchangeable, off-the-shelf parts. Gain can be adjusted using passive components, which are cheaper and easier to adjust.

Distortion and intermodulation are reduced significantly, and bandwidth is greatly increased. It also enables the construction of higher order filters without the use of inductors, which are heavy and prone to other problems. Though initially developed for vacuum tubes, the idea is very useful in transistor circuits, which can have wildly varying beta characteristics, even among devices on the same chip.

There are a lot of things to like about the video above, but my favorite part is the way he talks so earnestly about his failures, before finally succeeding.

Happy Birthday, Mr. Black!

Further reading:

Black’s Bell System Technical Journal article, Stabilized Feed-back Amplifiers, 1934 (PDF)

Harold Black’s IEEE Hall of Fame profile (PDF)

Michael Ciuffo built this neat soil moisture sensor for his girlfriend, since she’s had some bad luck with plants. He writes:

In the June 2012 issue of Nuts & Volts, they did a spread about making a soil moisture sensor with an iPhone interface:

And when I heard my girlfriend say that she has trouble remembering to water her plants, I put two and two together.

Most of the N&V article discussed the code required to interface with the iPhone, but the important part for me was that their soil moisture sensor was nothing more than a simple conductivity sensor. The more water in the soil, the lower its resistance.

Such a sensor doesn’t measure soil moisture in any kind of universal unit, but for a single sensor in a particular soil sample, the measured conductivity is repeatable and proportional to the moisture level. I call these conductivity units “AMU”s or “Arbitrary Moisture Units”.

Neat project and nice build!

Flight of the Navigator

MAKE | Component of the Month: Resistors.

Each month this year, we’re exploring a different electronic component, delving into what it is, how it works, and how you use it in projects. Last monthwe looked at batteries. This month, we’ll tackle the resistor, the job of which is to limit the flow of electricity and thereby control it, guiding it toward one component while protecting another. As always, we’ll start things off with an introduction to resistors via an edited excerpt from Charles Platt’s essential Encyclopedia of Electronic Components: Volume 1.

Mho the Resistor – Circuit Playground Plushie.

Tutorial: SMT Breadboard Prototyping Using Breakout PCBs @ The Adafruit Learning System.

Nothing is as fast and fun as prototyping on a breadboard, but at some point you will find that the chips you want to work with are only available in non-breadboard-friendly SMT/SMD (Surface Mount Technology/Surface Mount Device). Unlike most DIP chips and resistors, SMT parts do not have the leads going through holes in the PCB. Instead, they ‘float’ on top, with often-rectangular solder pads.

Although you may one day decide to use CAD software for laying out a custom PCB for these parts, you can do yourself a favor and prototype with SMT breakout/adapter PCBs. In this mini tutorial we’ll go over how to use these. It’s not hard, once you have the experience!

Learn more!

Why is my TI-99/4A in Black and White?

My first computer was a Texas Instruments TI-99/4A. Longtime readers may remember a previous article where we implemented TI-99/4A BASIC as a Scripting Language for modern computers. Recently I got nostalgic for the actual hardware so I got my 99 out of the closet where it had been for a decade or more.

Great teardown of a 1984 Keithley 197 microvolt DMM by KuzyaTech.

Tombstone Troubleshooting.

There have been many studies of the causes of tombstoning; some published, some not. They tend to focus on a single process parameter as the root cause of tombstoning. However, there is no single process change that is a sure cure for tombstoning! Those that claim otherwise are either uninformed or trying to sell you something. Rather than limiting your view to a single solution, EFD recommends you heed all of the studies. Like pieces of a puzzle, each study does not reveal the whole picture, but looked at all together, the picture is clear.

The issue of tombstoning has risen to prominence because, while components and assemblies have become much smaller over the last decade, overall assembly processes have remained much the same. As components become smaller, so should your process windows.

Last year, my friend Chris Novello closed the 2012 Open Hardware Summit with a demo similar to this performance — remixing SMB in ways nobody had ever thought of before — to wild and well-deserved applause, I might add. Here he is doing it again! He writes:

In this video, I directly manipulate the RAM state of Nintendo’s Super Mario Brothers to transform it from a game into a strange instrument.

First, I play the game as it is traditionally played.. but I have access to the game’s memory, so I change Mario’s Y position using the Madrona Labs Soundplane (a surface that sends data to the computer about where it is being touched). This is how I hover Mario during the playthrough.

Also, before I start playing, I flip a switch on illucia that I assigned to trigger recording — not video, but actually recording the entire memory state of the NES for each game frame.

Think about it – Mario’s universe is held in RAM, which the NES uses to draw his world for each frame of the game. By recording the entire state of the NES memory for every frame, I’m able to go back to any moment in Mario’s life.

So then I use the X-axis of the Soundplane to sweep through the timeline of Mario’s universe.

Not only that, but the Soundplane is multitouch, so I use a second finger to specify start and endpoints in a playback loop. Technically, this is similar to the way samplers and granular synths work in audio.. but with the entire memory state of the NES. Conceptually, it is like Super Mario meets Groundhog Day. Mario’s universe computer/time machine gets caught in hellish loops.

Then I start using illucia to send alien data into various other places in Mario’s universe, which makes for all sorts of audiovisual insanity amidst the spacetime loops. This is sort of like circuit bending, but in a protected sandbox – at any point I can revert back to the clean recording of RAM states (aka moments in Mario’s universe).

I then try to go back to “playing” the game, watching Mario navigate a melting world of glitched-out ephemera. I then push things into full on glitch insanity. I use a pair of rubberband mallets on the Soundplane to jump around in Mario’s universe while leaving illucia to send a heavy stream of alien data into Mario’s RAM state. I eventually (accidentally/luckily) land at a place that triggers the game over music, and end the take.

Will from FriedCircuits.us has been working on a new daisy-chainable LED Matrix Link prototype which makes use of a Maxim MAX7219 (which he will feature in his upcoming May wedding — fascinating!), so he has been investigating cheap sources for the IC suggested by friends and colleagues. His conclusion? Buyer beware when buying under market value on eBay. Learn more how to spot the fakes from his MobileWill blog:

I have been receiving feedback that I can use eBay suppliers to lower my price on the MAX7219. I had previously considered that option, but after some research I have found that a lot of people are receiving counterfeits on eBay. While some counterfeits may work, their reliability is questionable and that would make my product unreliable. I do not believe that it is “good business” to support businesses and companies which pirate technology and sell it as if it were legitimate. I sincerely hope everyone understands why I am skeptical about using an unknown supplier for parts. Here is a good forum post about coming across the fake variety: http://www.picaxeforum.co.uk/showthread.php?22481-Real-or-fake The more units I can sell initially will increase my per-part discount, which will allow me to lower my selling price.

For example if you look at the picture above, the line across the top is inline with pin 2. f you do a search on eBay or even Google image search you can see that they line up with pin 3. Also mine has a notch and the eBay ones all have a dimple. Not to mention there is no way someone can go to Maxim and get a price much lower then their lowest price they have.

You can buy [my new LED Matrix Link] on my Tindie shop here.

Read more.

Each week on the Adafruit blog we post up about amazing companies, people and articles about being a MAKER and a business. Over the years we’ve shared how we run Adafruit, published code from our shopping cart system and given presentations on running an open-source hardware company. Every Monday we’re going to try to collect some of these resources and tag them #makerbusinessmonday & #makerbusiness. They’re in our popular Maker Business category as well, enjoy!

If you are in the New York City area and have been looking to gain the skill to manufacture your own PCBs for the projects you are developing — perhaps on your way to launching a brand new kit or product — then check out the Zahn Center’s upcoming PCB making classes:

WHEN: April 6, 2013 @ 10:00 am – 6:00 pm

WHERE: Zahn Center, Room B20, Steinman Hall, 140th Street and Convent Avenue, New York, NY 10031

COST: $150 (plus fees)

Our first “Make your own PCB” class will be given by PCB designer extraordinaire, Jonathan Hirschman. In this class we’ll be helping you design and build your very own Arduino clone, similar to the one shown. The class is designed for everyone, of all skill levels, with no knowledge of electronics required – just a desire to learn and make.

The class will be given in two Saturday sessions (April 6th and April 20th, from 10am – 6pm). In the first session, you’ll learn about PCB design software, and then you’ll create your own Arduino clone design, and send your design out for fabrication. Two weeks later, you’ll be building and assembling your boards!

Even though this class is newbie friendly, we’ll be doing a pretty deep dive. You’ll learn how to read datasheets, how to design components in the layout software, power and ground planes, even how to make funky graphics. Want skulls and flames on your clone? No problem! We’ll also talk about the different manufacturing shops out there, pricing, location and what are some of their pros and cons. In the second session you’ll learn all about assembly and mounting, and how to correct when the tiny legs on your microntrollers don’t quite line up….

Read more.

]]> http://www.adafruit.com/adablog/?feed=rss2&p=57992 0 http://www.adafruit.com/blog/2013/03/20/cern-consolidating-lhc-splices/ http://www.adafruit.com/blog/2013/03/20/cern-consolidating-lhc-splices/#comments Wed, 20 Mar 2013 13:31:56 +0000 johngineer http://www.adafruit.com/blog/?p=57646

Back in the fall of 2008, the Large Hadron Collider experienced a setback when a section of the liquid helium coolant exploded. Aside from the damage caused by the explosion, there was damage to the electrical system. The lack of coolant resulted in a loss of superconductivity, which caused the temperature of the conductors to rise to damaging levels — the conductors were still carrying thousands of amps of current, but their resistance had increased by several orders of magnitude. Ohm, the humanity!

To help prevent such an occurrence in the future, the LHC team has begun installing special shunts, which will help lower the resistance of the conductors at non-cryo temperatures, in order to prevent similar damage from happening again.

On 19 September 2008, during powering tests on the Large Hadron Collider (LHC), a fault occurred in a superconducting interconnection between two magnets – a dipole and a quadrupole – resulting in mechanical damage and release of helium from the magnet cold mass into the tunnel. Proper safety procedures were in force, the safety systems performed as expected, and no-one was put at risk. But the fault did delay work on the LHC by six months.

After the incident, CERN engineers decided that such interconnections should be upgraded to avoid similar electrical faults in future. As a precaution, beams in the LHC were accelerated below the LHC’s design limit for the first three years of running. Upgrading the interconnections will be one of the main activities at the LHC during its two-year shutdown, allowing the LHC to run at 7 TeV per beam when it starts up again.

There are 10,000 “splices” – superconducting connections between magnets – on the LHC. Each splice carries 13,000 amps.

In the video above, Jean-Phillipe Tock of the Technology department explains how, over the next 18 months, technicians will add an additional piece – a “shunt” – to each splice. The shunt is a low-resistance connection that forms an alternative path for a portion of the current in the event that the splice loses its superconducting state. A total of 27,000 shunts will be installed in the 27-kilometre accelerator.

[vid link]

There are thousands of devices in the ‘default’ library that comes with EagleCAD but whaddyaknow, the exact package/device you need isn’t always going to be one of those thousands. However, instead of making a brand new device from scratch every time you can often ‘merge’ two existing devices, or at least reuse the SMD package. Not only will you save time, but it can minimize mistakes. (Note I say itcan – be sure to always always triple check pinouts, package sizes, dimensions and more!)

This little tutorial will show you how to create a new package for an existing device. It’s not a beginner tutorial so you’ll have to learn how to use Eagle first, but its one of those skills that can save you tons of time.

The chip I’ll be looking to add today is this fine quad 2-input NAND Schmitt trigger. Specifically, I want to add the TSSOP package.

Learn more.

One of the statements you read a lot when you’re learning about digital logic is that NAND gates possess functional completeness, which means that they can be combined to implement any Boolean function.

Kevtris decided to take this idea to it’s logical* conclusion:

What is a NANDputer? it’s a computer made out of nothing but NAND gates of course! I dunno why, but I thought it’d be fun to make this. I first had to work out how various parts of a CPU would be made out of NANDs, did a bunch of tests and went to town.

The design took about 2 months to come up with and make. At the bottom of the post is a few statistics on gate usage and count of each type (2 input, 3 input, 4 input, etc). As I suspected, the quantity vs. gate input count follows a pretty steep curve, with most gates being 2 inputs, and the fewest being 13 input gates.

Everything on the design is made out of NAND gates, even the 7 segment decoding. The last PCB though has a few non-NAND gate chips like an NES PPU and a serial chip and stuff, but it’s just a peripheral board and is not part of the NANDputer proper. (Eventually I want to make a NAND UART and replace that peripheral board).

The basic architecture of the computer is actually fairly conventional. There’s an accumulator, instruction skipping (like on PIC) for decision making, a full ALU (and, add, or, xor, subtract, add with carry, subtract with borrow, set all bits, clear all bits, shifting), 8 bit registers, separate RAM/ROM areas (harvard arch), and bit set/clearing. There’s a 3 level stack, and even an interrupt!

While the CPU architecture is fairly conventional, the way it is implemented isn’t. I went with a bit-serial setup on here to save gates. The ALU for example is only 1 bit, with a “latching” carry so operations are performed a bit at a time on the 8 bit registers/memory. The program counter is also bit-serial, and on the first youtube video you can see the carry propagating during the incrementing of it.

Neat design and awesome build — way more exciting than the Galaxy Nexus IV Episode 2, or whatever it’s called.

Happy Friday!

*pun most definitely intended.

Thanks to hacker/maker Drew Fustini from Pumping Station: One for this great tip from SXSW this year:

Jeff McAlvay is showing off an Open Source Hardware Pick and Place machine at SXSW that he and other Pumping Station: One members have built. It uses a Raspberry Pi for computer vision and node.js web interface. He was interviewed by Slashdot yesterday!

I find this project really exciting, especially after Ladyada spent time investigating a tremendous range of Pick and Place machines out west a few weeks ago.

From Slashdot TV:

SXSW Create is one of a handful of sub-shows at SXSW which don’t require an expensive badge — it’s maker-oriented and small, and a few blocks from the slicker parts of the convention. (The local ATX Hackerspace was there showing off robots and giving out soldering lessons and blinkies, without a single corporate pitch.) Under the same tent, I met with Jeff McAlvay, creator of Board Forge, which Jeff hopes will make small-run circuit board creation as easy and accessible as small-scale 3-D printing has become in the last few years. (“Think MakerBot for electronics.”) The prototype hardware McAlvay had on hand looks — in fact, is a 3-D printer, albeit one lower-slung than the ones that make plastic doo-dads. That’s because the Board Forge’s specialized task of assembling circuit boards requires only limited vertical movement. It’s using the open-source OpenCV computer vision software and a tiny camera mounted on a movable head to accomplish the specialized task of selecting and placing components onto the boards. The tiny electronic components are lined up in strips on one side of the device, where that smart head can grab them for placement. The brains of the operation include an Arduino-family processor for basic controls, and a Raspberry Pi for the higher-level functions like computer vision. The projected cost for one of these machines — about $2000 — should put instant-gratification machine-aided circuit creation in reach of schools and serious hobbyists, but there’s plenty of work before it’s set for sale to the public; look for a Kickstarter project in the next few months.

Read more.

Each Friday is PiDay here at Adafruit, be sure to check out our posts, tutorials and new Raspberry Pi related products. Have you tried the new “Adafruit Raspberry Pi Educational Linux Distro” ? It’s our tweaked distribution for teaching electronics using the Raspberry Pi. But wait, there’s more! Try our new Raspberry Pi WebIDE! The easiest way to learn programming on a Raspberry Pi.

We now have Raspberry Pi Model B with 512MB RAM in stock and shipping now!

We received a tip that Professors Michael McCune and Hart Marlow are up to interesting projects at NYCCTfab — exploring Rhino, Grasshopper, and Firefly and a ZPrinter 650 to explore embedded electronics in 3D printed objects. More to come soon about their use of Arduino Unos, RGB LEDs, and photoresistors and/or IR distance sensors to control LED output.
From @NYCCTfab.

No #texfab but Hart Marlow and @mcc_une’s #fabrication class today at #CityTech is next best thing #gh3d #3Dprint pic.twitter.com/XWoEquzVCx

Read more.

Every Thursday is #3dthursday here at Adafruit! The DIY 3D printing community has passion and dedication for making solid objects from digital models. Recently, we have noticed electronics projects integrated with 3D printed enclosures, brackets, and sculptures, so each Thursday we celebrate and highlight these bold pioneers!

Have you considered building a 3D project around an Arduino or other microcontroller? How about printing a bracket to mount your Raspberry Pi to the back of your HD monitor? And don’t forget the countless LED projects that are possible when you are modeling your projects in 3D!

The Adafruit Learning System has dozens of great tools to get you well on your way to creating incredible works of engineering, interactive art, and design with your 3D printer! If you’ve made a cool project that combines 3D printing and electronics, be sure to let us know, and we’ll feature it here!

DIYROCKETS and Sunglass.io challenge you to collaboratively design an Open Source 3D printed rocket engine that could carry nano-satellites into space! Via MAKE:

​THE CHALLENGE
​Over the last few years multiple companies, institutions and individuals have started building nano-satellites and other small satellites. These little satellites are packed with electronics and range from the size of a computer chip to a smart phone to a pumpkin. With their communication and research capabilities, they have multiple applications working individually or in coordination with one another. But, with the high cost of earth to space transport, how in the world are they going to get up into space?

We challenge YOU to design a 3D printed rocket engine that could become part of a propulsion system and vehicle to carry nano-satellites into space….

Read more.

Two-Layer PCB Etching @ Blondihacks. Quinn writes -

Etching PCBs is a topic I’ve covered quite a bit already, here and especially here. You might think I’ve beaten this copper and fiberglass horse to death. Well, I don’t want to be a one-trick pony, so there’s one more thing to try. Lucky for you, I’ve run out of horse-themed metaphors so I’ll just get to it.

I’ve been wanting to try two-layer PCB-making for a while now, because the boards I’m making for Veronica are reaching complexity levels where the top-side jumper count gets a little nuts. I also have lofty dreams of running boards above 10Mhz, and those jumpers will quickly become a liability. Furthermore, building jumpers is quite a bit of work, so if I can eliminate that, it would be a real win.

Sebastian Tomczak continues his series on prototyping with a step-by-step tutorial on going from schematics to a breadboard. He writes:

In breadboard basics 1, we looked at how a breadboard is structured. In this post, we are going to look at how to move from a schematic to a breadboard, and the step-by-step decisions that would be involved in doing so.

We’re going to build a simple audio amplifier! The aim of this post is to:
1) Give you the skills to work confidently with a breadboard
2) Give you the skills to read simple electronic schematics
3) Give you the skills to translate a simple schematic onto a breadboard for real-world use

Great, informative post by Ken Shirriff of the Intel 8085 register file design and implementation. He writes:

On the surface, a microprocessor’s registers seem like simple storage, but not in the 8085 microprocessor. Reverse-engineering the 8085 reveals many interesting tricks that make the registers fast and compact. The picture below shows that the registers and associated control circuitry occupy a large fraction of the chip, so efficiency is important. Each bit is implemented with a surprisingly compact circuit. The instruction set is designed to make register accesses efficient. An indirection trick allows quick register exchanges. Many register operations use the unexpected but efficient data path of going through the ALU.

While the 8085′s register complement is tiny compared to current processors, it has a solid register set by 1977 standards – about twice as many registers as the 6502. The 8085 has a 16-bit program counter, a 16-bit stack pointer, 16-bit BC, DE, and HL register pairs, and the 8-bit accumulator. The 8085 also has little-known hidden registers that are invisible to the programmer but used internally: the WZ register pair, and two 8-bit registers for the ALU: ACT and TMP.

Oona Räisänen is back with more annotated auditory phenomena. This time, it’s a frequency sweep on a cassette tape. She writes:

The tape on a compact cassette imposes all kinds of noise and distortion on a recorded signal. Much of it is so quiet that it’s practically inaudible, but with some signal processing we can zoom into some fascinating details.

Of particular interest are the sidebands caused by variations in the drive mechanism (flutter).

For those of you who have been following along for the past two weeks, here’s the third part of Fran’s “Make Your own Printed Circuit Boards” series, focusing on drilling!

“Ask Fran” from Fran Blanche:

This is the third of my 3-part vlog mini-series on high quality PCB manufacturing. In these vlogs I will show the specialized tools and equipment that you will need to make your own high quality PCB’s from scratch, with step by step demonstrations of each stage – from rendering and checking the artwork, to applying the resist to copper clap boards, to etching, to drilling the PCB’s.

[Note: Some audio issues in this video due to a glitch in the software encoding that could not be remedied. Drat!]

The PCB artwork and schematics for the Apollo Launch Vehicle Digital Computer Logic Devices are available on my Design and Engineering page.

Read more.

Great piece by artist Melanie Hoff.

Seriously… wow.

[via Colossal]

How to get to the second i2c port on a Pi v2:

In the upper left hand corner of the board you can see the GPIO header.  Below that is the P5 header footprint, a 2×4 series of vias.  You won’t see the P5 label until you flip the board over.

Now, there are some folks that will tell you the only way to get to the second I2C bus is to access the camera S5 header (or the S2 header).  That would involve some incredible soldering work, or a socket.  I don’t have the socket, and my hands aren’t good enough to solder at that pitch.

However, I can solder that P5 header.  The unfortunate thing is that the P5 header is really close to the GPIO header.  Using the P5 header while using Lady Ada’s Pi Cobbler header may be problematic.  I took some long headers and soldered them in place, at a slight angle….

Read more.

Each Friday is PiDay here at Adafruit, be sure to check out our posts, tutorials and new Raspberry Pi related products. Have you tried the new “Adafruit Raspberry Pi Educational Linux Distro” ? It’s our tweaked distribution for teaching electronics using the Raspberry Pi. But wait, there’s more! Try our new Raspberry Pi WebIDE! The easiest way to learn programming on a Raspberry Pi.

We now have Raspberry Pi Model B with 512MB RAM in stock and shipping now!

My friend Bob recently tweeted this photo of a letter he wrote back in his salad days, ordering a few diodes from Poly-Paks in Massachusetts.

Of course, today, a diode is just a click away!

I just got back from a quick day trip to Embedded World in Nuremberg.  EW is one of the better embedded shows since it’s a lot more engineering and lot less marketing than some of the competing shows in Europe (Electronica, etc.).  Click on through if you’re interested in my thoughts on my brief (if somewhat difficult to digest!) trip to Europe’s best show!

So, why would I go to a trade show in 2013, you ask?  Inevitably I know the details about 99% of the interesting products before they’re presented live at the show … it’s true.  Trade shows aren’t really the place you go to to hear what’s new anymore.  Companies know this too and are cutting back on what used to be a huge chunk of the marketing budget.  Spending $1,000,000 at a trade show might not be the best return on investment in this climate, and it seemed like the distributors were more center stage than was the case in the past.

BUT these kinds of shows are still really good for two things:

• It’s a great way to catch up with former colleagues since most engineers in the embedded world tend to move around between the same big companies (ST, TI, NXP, Atmel, Renesas).  And hey … everyone loves a bit of gossip and beer on another company’s dime!
• It’s still the best way to get through the impenetrable anonymous support barrier in the companies you want to work with if you don’t already have a contact there.

Number one inevitably involves lots of beer and lots of food.  Yesterday wasn’t a disappointment there!

Number two is less likely to cause a heart attack.

Even a quick one night trip to these things can end up costing $1,000 or so, but chatting 15-20 minutes face to face with the real apps engineers, product designers or product managers for whatever you’re interested in instantly gets you through the anonymous web support barrier, and your chances of getting the answer you’re looking for goes up by several orders of magnitude.  You can get the name of the person that really matter, or at least start on level 2 or 3 support, rather than tossing your bottle into the sea with level one at support@willthiswork.com?

You can also try out a $15,000 scope that’s just so much better in person than it looked on paper and try to convince yourself not to buy it … but I think that should be classified as work-related stress and be avoided rather than listed as a benefit or sought after outcome.

Back to number two, though.  I came back with 3-4 business cards that I think are helpful to me to explore some new ideas, or get a bit further with some products I’ve already been using.  In that respect, it was well worth the 700 EUR it cost me and the too long flight through Zurich (no direct Paris-Nuremberg flight available), the hotel, etc.  I met a few really helpful people, saw a few cool projects, caught up with some former colleagues I appreciate, and saw some things that made me rethink certain ideas.

So what did I see?  Two things jumped out at me.

NUMBER ONE: The show was 100% ARM.  Like, seriously … I didn’t see anything 8-bit except maybe the odd token board on a dusty back shelf somewhere, and this was from every big MCU manufacturer.  If you’re in university now and going into embedded and want a job after your studies, ARM Cortex is where you want to be.

NUMBER TWO: Judging by EW, the only business plan that seems to exist in Asia these days is making wireless modules!  Flee in terror if your great business idea is another IoT wireless module design or eco-system … you’re doomed to compete on price in a market with razor thin margins and (literally!) hundreds of competitors with sub $10 solutions-looking-for-a-problem!  I love wireless.  I make wireless modules for the fun of it.  I’ll never go into the wireless module business!  Of if I do, please slap me.  Twice.  Want to do something with wireless?  Aim higher!  Solve a real problem where wireless is just something in the background, and charge $100 for it rather than focusing on the modules and selling them with 10% margins at $9 a piece!  Why are people doing modules?  Because they don’t have a problem to solve, and they just want to piggy back on that big idea that never seems to materialize.  Please … don’t remind me of the fridge that orders milk for me.  It’s a warning sign that we’ve been using the same  use case since 1995!

But hey … photos or it didn’t happen, right!

I finally found a good use for all those giant neglected ARM9 BGA parts I’ll never use (see point 1 above … ARM Cortex is where it’s at!) …

And in the ‘things you’ll only find at an embedded engineering conference’ department …

There really is a good business case behind this, though, since a lot of expensive (six figure+), highly specialized test gear is based on floppy drives.  When you have a $200K analyzer with a dead floppy drive I bet it’s easy to convince them to spend $1K on something like this … though I admit I took the photo for the lulz:

This thing really was huge … though it did look kind of dodgy as cake’s go and not entirely lead free, so it was easy to resist biting into it …

I don’t know .. I just seem to have some sort of weird fetish for test fixtures, and fancy probe holders like this.  I actually have something similar and rarely use it (I’m hardly inspecting bare dies here) … but the attention to detail in this stuff is still fun to look at …

Anyone else make the trip to EW2013?  Feel free to post your thoughts up on the comments below!

Making the rounds today, this excellent video by Monty Montgomery about digital (audio) signals. It’s a great discussion of how sampling, dithering, anti-aliasing and bandwidth limits all work together to capture and reconstruct a signal. It’s also suggested that you check out the accompanying wiki — very helpful, indeed, because there’s a LOT of information in this video.

Here is the part two of Fran from Frantone’s “Make Your Own Printed Circuit Boards” series! She wraps this up next week.

From the video description:

This is the second in my 3-part vlog mini-series on high quality PCB manufacturing. In these vlogs I will show the specialized tools and equipment that you will need to make your own high quality PCB’s from scratch, with step by step demonstrations of each stage – from rendering and checking the artwork, to applying the resist to copper clap boards, to etching, to drilling the PCB’s, to component placement and soldering, and finally to defluxing and finishing.

The PCB artwork and schematics for the Apollo Launch Vehicle Digital Computer Logic Devices are available on my Design and Engineering page.

Read more.

]]> http://www.adafruit.com/adablog/?feed=rss2&p=55601 0 http://www.adafruit.com/blog/2013/02/25/introduction-to-boost-converters-video/ http://www.adafruit.com/blog/2013/02/25/introduction-to-boost-converters-video/#comments Mon, 25 Feb 2013 09:01:13 +0000 johngineer http://www.adafruit.com/blog/?p=55554

Great video by Jeff Feddersen about the ins and outs of boost converters. He writes:

Boost converters (or step-up converters) are in a class of circuits called DC-DC conversion circuits. These can operate more efficiently than linear regulators like the 7805, and unlike linears they can be designed to have a higher output voltage than their input voltage – potentially useful for low-voltage sources like some steppers.

]]> http://www.adafruit.com/adablog/?feed=rss2&p=55554 0 http://www.adafruit.com/blog/2013/02/20/charming-light-up-ohmmeter/ http://www.adafruit.com/blog/2013/02/20/charming-light-up-ohmmeter/#comments Wed, 20 Feb 2013 15:44:25 +0000 Becky Stern http://www.adafruit.com/blog/?p=55236

This fun desktop ohmmeter displays resistor values numerically and lights up the colored bands to match. via Hackaday

]]> http://www.adafruit.com/adablog/?feed=rss2&p=55236 0 http://www.adafruit.com/blog/2013/02/19/the-super-supercapacitor-2/ http://www.adafruit.com/blog/2013/02/19/the-super-supercapacitor-2/#comments Tue, 19 Feb 2013 13:50:24 +0000 adafruit http://www.adafruit.com/blog/?p=55150

Ric Kaner set out to find a new way to make graphene, the thinnest and strongest material on earth. What he found was a new way to power the world.

]]> http://www.adafruit.com/adablog/?feed=rss2&p=55150 5 http://www.adafruit.com/blog/2013/02/18/frantone-series-on-high-quality-pcb-manufacturing/ http://www.adafruit.com/blog/2013/02/18/frantone-series-on-high-quality-pcb-manufacturing/#comments Mon, 18 Feb 2013 12:00:00 +0000 Matt http://www.adafruit.com/blog/?p=55043

Here’s the first of a three-part weekly series from Fran showing her process for manufacturing PCBs, from Fran’s Writings on Design and Engineering. Check back next week for the next episode!

This is my 3-part vlog mini-series on high quality PCB manufacturing, and introduction to my “make your own LVDC logic devices” project.   In these vlogs I will show the specialized tools and equipment that you will need to make your own high quality PCB’s from scratch with my own refined methods, with step by step demonstrations of each stage – from rendering and checking the artwork, to applying the resist to copper clap boards, to etching, to drilling the PCB’s, to component placement and soldering, and finally to defluxing and finishing. 

More about my PCB manufacturing process here - 
DIY Printed Circuit Board Manufacturing

Read more.

]]> http://www.adafruit.com/adablog/?feed=rss2&p=55043 0 http://www.adafruit.com/blog/2013/02/13/usb-tester-oled-backpack-with-display-by-mobilewill/ http://www.adafruit.com/blog/2013/02/13/usb-tester-oled-backpack-with-display-by-mobilewill/#comments Wed, 13 Feb 2013 06:00:00 +0000 Matt http://www.adafruit.com/blog/?p=54489

A new great testing shield component from MobileWill to complement William’s USB Tester:

Today we have started the fundraiser for the USB Tester OLED backpack with the display. This is a great addition to the USB Tester, which makes it easy to monitor voltage and current for any USB device. Now you don’t even need your DMM. You can use this to see how much power your Raspberry Pi is using or that custom Arduino based project you are working on. This is a great way to make sure you aren’t getting a voltage drop due to that USB hub you are using. Check out the product description below and thanks for your support. You can back the project here….

Read more.

]]> http://www.adafruit.com/adablog/?feed=rss2&p=54489 0