Wednesday, June 8, 2016

Happy Birthday to AllJoyn Nashville!


Last night I had the pleasure of kicking off the inaugural meetup of AllJoyn Nashville. It was a huge success with about 30 people there once everyone arrived.

The meetup was a joint effort between the NashMicro user group and AllJoyn Nashville. NashMicro is a user group of Nashvillians interested in general microcontroller & electronics topics. Since AllJoyn is a topic of interest to NashMicronians (NashMicro members), it made sense to host this meeting with them.

Meeting together was a big win for both groups. NashMicro had the benefit of an interesting topic, good food, and prizes that AllJoyn Nashville brought. AllJoyn Nashville benefited by having an established member base of over 400 NashMicronians to introduce themselves to and a great location to meet. Until AllJoyn Nashville has enough membership and interest that it makes sense for us to meet on our own, we will continue to have joint meetings with NashMicro at least every 4-6 months. For anyone looking to start an AllJoyn group, I would highly recommend cross promoting with other similar minded groups in your community if possible.

The meetup started with a taco bar from Swanky’s. You can’t have an after work meetup without food if you want folks to stay for the duration and socialize. A huge thanks goes out to the Allseen Alliance for picking up the tab for the food & drinks!


For the main presentation, I gave my “AllJoyn All The Things” talk that I had presented at CodeMash 2016 back in February. It was well received there and acted as a catalyst to make me want to further study AllJoyn and find others in the area also interested. The presentation was also well received at the AllJoyn Nashville meetup and some folks I talked to afterwards have decided to actively pursue integrating AllJoyn into devices they are currently developing. That’s the kind of feedback every speaker loves to receive.


AllJoyn Nashville wasn’t really something I’d considered starting on my own. After giving the presentation at CodeMash, I put the talk on the NashMicro calendar and it was advertised as a MeetUp event. The folks at the Allseen Alliance (a Linux Foundation collaborative project) took notice that I was promoting AllJoyn and approached me about becoming an AllJoyn Ambassador. One of the primary jobs as an Ambassador is to lead an AllJoyn user group. And as they say, the rest is history… If you’ve ever had any hesitation about speaking at a user group or conference, let this serve as a good example of one of the unexpected benefits that can come from it.


My presentation makes heavy use of LIFX WiFi bulbs. So, once I became an AllJoyn Ambassador I immediately took advantage of my new title and connections and contacted the folks at LIFX, who are also Allseen Alliance members, about sponsoring my efforts. They were very generous and agreed to donate some bulbs and coupon codes for me to give away. I gave away four LIFX Color 1000 bulbs at this meeting and the recipients were all very excited to receive them. Many thanks to LIFX for being the first AllJoyn Nashville sponsor! We hope its a mutually beneficial partnership for many years.

I’ll be contacting many more Allseen Alliance members in the near future about becoming sponsors. If you know anyone that would be interested in becoming an AllJoyn Nashville sponsor, please contact me.

NashMicro also gave away books from No Starch Press and a free software license from JetBrains. Many thanks to those sponsors, also!

I also need to add a special thanks to the folks at Emma for letting us meet with NashMicro at their wonderful Bistro space.

Overall, I’m very glad that we’ve started this group in Nashville and I hope that it leads to more companies integrating AllJoyn into their products. If you have an interest in AllJoyn and you’re near Nashville then come join us. If you’re not in our area, then apply to become an Ambassador and start an AllJoyn user group of your own.

The attendees asked me many questions about AllJoyn that I didn’t fully know how to answer. So, its time to go learn! That’s part of what’s so great about participating in a user group like this. We’re all in it together and no one expects any one of us to be an expert of all things. But, when we divide and conquer and all come back to the next meetup with just a little more knowledge to share then we eventually all become experts.

Happy birthday AllJoyn Nashville! Let’s go “AllJoyn all the Things!”

Wednesday, November 4, 2015

Valorworks Soldering Badge

This is a soldering badge kit that I designed for Valorworks, a maker group getting started at Valor Collegiate Academy. The design is based on their school's logo.  Costs came out at $2.05 per board (qty 50).

Altium CircuitMaker was used to design the schematic & PCB.  The files are open source and available here.  The design uses four flashing 3mm orange LEDs on the points of the compass and a single 0603 SMT blue LED in the center. They're all powered by a single 3V CR1225 coin cell battery.

The design works well with one exception.  The battery voltage drops off quicker than I'd expected and as a result it falls below the 2.8V forward voltage of the blue LED within 10 minutes and it stops functioning.  The orange LEDs continue to function for another 48 hrs. We're using the cheapest batteries that can be found on eBay.  So, these numbers can likely be greatly improved by simply using a higher quality battery.  For this batch, it was decided to eliminate the blue LED and its resistor.  If a second batch is needed in the future then we'll consider a hardware revision.

Assembly instructions are in the video below.  Note that the steps to solder the blue LED and SMT resistor are not needed in the v1.0 badge.

If you or your company are interested in having a custom soldering kit created for a workshop, birthday party or other event contact me with details.

Saturday, January 10, 2015

Gadgeteer vs Arduino vs Phidgets recently ran an article called "Arduino vs. Phidgets - Dev Time Trials" which brought to attention a blog post by Ken (?) called "Hardware Protoyping Speed Test: Phidgets vs Arduino" which I thought was a rather fair set of tests for comparing development speed and costs for three simple projects. My objective is to run these same tests using the Gadgeteer rapid prototyping system and report my results. Of course, like any article of this sort there are always going to be some lively comments from the readers regarding the validity and bias of tests.  I fully expect that this article will generate plenty of its own.

Like [I suspect] Ken, I am not being paid to write this article and have not gone to every length to make everything as objective and scientific as possible simply because I am not interested in spending more than a few nights with these tests and producing the video.  However, I do feel that my tests are in line with the tests that Ken performed. Ken introduced us to Phidgets as an alternative rapid prototyping system for hardware.  His tests showed that Phidgets is indeed a faster development system than Arduino.  However, as he and the readers of the article pointed out there are several negatives to going this direction including:
  1. Cost - the Phidgets projects were considerably more expensive than the Arduino projects.
  2. PC Tether - Phidgets must be connected to a PC at all times.
  3. Proprietary

What is Gadgeteer and why use it?

My favorite hardware system for rapid prototyping is Gadgeteer.  Much like Phidgets, it uses modular components combined with software to provide a system which makes it possible to prototype extremely quickly.  In these tests I will demonstrate this.  I am also a big fan of Arduino and regularly use it in projects.  However, for rapid prototyping I haven't found anything better than Gadgeteer.  I have never used Phidgets myself.  Any statements about the platform come from Ken's article.

Gadgeteer also addresses the concerns numerated above with Phidgets.  You will see that the project costs when using Gadgeteer was only nominally higher than that of Arduino.  Considering the productivity gains, I believe it to be worth the investment.

Gadgeteer is microcontroller based.  So, a PC is only needed for programming and debugging.  Once that's done, you can untether it and power it from any DC source as you can with Arduino.
Gadgeteer is open source and is based on the open source .NET Micro Framework (NETMF) project.  Most of the modules and some of the mainboards are also open hardware & software.  Vendors can extend the core framework and add their own proprietary software to mainboard firmware.  However, no proprietary functions were used in my tests.

The Tests!

For more information about the tests, I encourage you to read Ken's article.  I'm going to focus this post on just showing my results and detailing concerns I uncovered when necessary.

TEST #1 : Blink an LED (aka "Hello World!")

For this test, I used the following components.
The results...

Some people may complain here that I didn't manually wire up an LED & resistor as Ken did in his tests.  I say that defeats the purpose of rapid prototyping.  One of the main advantages of Gadgeteer is that I don't need to know how to wire up circuits in order to quickly make something that works.

TEST #2 : Move a Servo 

For this test, I used the following components.
One thing I felt was an error in Ken's tests were that he didn't use the same servo in both tests but instead used a slightly more expensive Phidgets branded servo for the test of the Phidgets board.  Since the brand of servo really shouldn't matter, I thought it would be a more fair comparison to exclude the cost of the servo from the prices and assume that the same servo was used in every test since they all basically function the same way.

The results...

Some of the readers of Ken's article complained that he use "libraries" in his tests and I anticipate some will complain that I did the same.  To that I'll respond "you betcha!".  Built-in module drivers that have been written and tested specifically for a known module circuit that are easy to wire in via drag & drop programming is another big reason that rapid prototyping with Gadgeteer is so much faster.  Even if you have the libraries available to you in Aduino, you are going to have to locate them and figure out how to include them in your project which takes time that you do not have to spend with Gadgeteer.

TEST #3 : Pedometer

For this test, I used the following components.
The results...

Here we can see that as the complexity of a project increases, the development time saved by Gadgeteer really pays off.  It's also important to note that the cost of the Gadgeteer solution is only slightly higher than that of the Arduino solution and almost four times cheaper than the Phidgets solution.


Here I've plotted a summary of the results from the three tests.  The Y axis shows development time and the bubble size shows cost.  It is evident from this comparison that Gadgeteer makes a very good choice when choosing a rapid prototyping system.

Some readers of Ken's article commented that Phidgets was faster but due to the cost it wouldn't be useful for creating final projects.  As you can see in the cost comparisons of the Gadgeteer & Arduino solutions, Gadgeteer solutions can make very good options for many final projects.  In fact, I have consulted with a company in the past that is doing this very thing in a commercial product.  Certainly, if a company's volume gets high enough then it makes sense to convert to a custom PCB solution.  But if you are a start-up with more ideas than engineers then a Gadgeteer based solution is a very viable option.

Although at times it may sound like I'm getting paid to write this article, that is not the case.  I am just a really big fan of the Gadgeteer prototyping system and I'm excited to show you why.  There's much more power including rich debugging, inline help, and the full power of Visual Studio that these tests do not even begin to demonstrate.  

For more information, I encourage you to follow my blog and Gadgeteerin' YouTube channel for more information.  For up to the minute news about Gadgeteer, follow me on Twitter as @Gadgeteerin.

You can find all source code used in the video here.
This post made Hackaday!