That time I got accepted to IgniteMpls, and then booted with out recourse.

I submitted a talk to IgniteMpls several months ago. These are 5 minute slots, with 22 slides, 15 seconds/slide. To be honest- I don’t remember the exact time/day- as I never got an email that my submission was processed.

April 6th I get an email that I have been accepted to speak! Awesome!

On April 19th, I send an email to Patrick Kuntz, the organizer about my info (picture, bio, twitter) – and also let him know that I may have a last minute work trip that week. It is unfortunate when last minute work travel comes up, but being the responseble adult, I figured it would be the right thing to let them know well in advance, instead of being that jerk and canceling last minute either the day or week of the talks.

Boy, was I wrong, and they sure taught me a valuable lesson. Keep your mouth shut. (<–This is actually a really bad thing to do.)

Patrick responded with-in 10 minutes (2:08pm) to me with:

“I need to know today. Now. If you are speaking or not.”

Another ten minutes go by with out response from me, and I get another email (2:28pm) – this time he is basically threatening my talk slot:

“David, I can’t leave this to chance. Please let me know within the hour WHEN you’re going to know FOR SURE whether you’ll be speaking. If I don’t hear back from you with an answer to this question, I’ll need to find a replacement. I’m sorry to draw such a hard line, but we’ve got to make sure we’ve got a show to put on. Thanks much.”

Later that night after not being able to respond, I get another email (8:03pm) from Patrck:


“David, Alright, dude. You didn’t get back to me. I gotta call it. We’re going to remove you from the line-up for May 10. The next Ignite is November 3. Talk submissions will open in late July.”

So in the span of several hours, while I’m working, and  then teaching a Raspberry Pi class at a Library, I am forcefully removed with out any sort of recourse.
I respond via email (10:38pm):


“Hey Patrick, I’m waiting to hear back from my contact in the UK about if the on-site work trip is actually happening. I will get back to you by the end of the week with details.”

Patrick, who clearly does’t know my name anymore, then comes back with an email (11:11pm):



I’m sorry, you misunderstood. You committed to speaking at Ignite almost two weeks ago. Since your commitment is now uncertain, we’ve removed your talk from the line-up and awarded the slot to another speaker. An enormous amount of volunteer hours, money, and effort on the part of our speakers goes into producing an Ignite event. We received nearly 100 talk submissions, and we only announce speakers and sell tickets after we get a firm commitment from our speakers. It is unreasonable to expect that we could pivot and fill your slot with a quality, polished talk on just a few days’ notice. So again, I’m sorry, but we cannot wait. To be clear, you will not be speaking at Ignite Minneapolis on May 10. Another speaker has already committed. 

You are invited to submit this or another talk proposal for the November 3 event.



In the last 15+ years of submitting and speaking at conferences, I’ve never had such an unprofessional exchange such as this one. I would also never want to subject a new speaker to this. It certainly would kill any kind of positive feelings I might have had for public speaking. Speakers are people too- and clearly they seem to have forgotten that.

It’s any wonder why anyone would submit to IgniteMpls. Let alone volunteering my time to create the material, and then present it. If no one submits, you don’t have any content. Booting someone from a speaking slot with out any kind of dialogue is unprofessional, and I will never submit nor can I encourage anyone in the community to submit to something where the presenters are not respected (time and content). This is a volunteer speaking slot, and I’m doing this for the benefit of the community.

What pisses me off the most is that I came to them with honesty, openness, and an effort to be upfront. Unfortunately, that backfired on me. Booting someone unjustly three weeks out sends a message to the community, and any potential speaker.

But when you have nearly 100 submissions and 18(16?) slots, apparently it’s easy to be a dick to your presenters. This is utterly and completely wrong. We should be respecting the speakers- and working with them. This is not how an event should be run. Ever.

I help run a conference in Chicago, and we do have a few people that let us know if they can’t make it- and we work with them. We don’t forceable remove them from their talking slot. There have only been a few times that I have ever had to worry about something like this, and it’s never easy, and believe me it sucks more for me then it does for them to not be able to participate in a local conference or event.

I hope the sponsors take notice of this too- is this the kind of community we should be perpetuating here in Minneapolis? I don’t think so. By writing this, I might have burned a bridge with IgniteMpls- however no other speaker should be treated like I have been. It’s rude, nasty, and unnecessary. We are all adults, with full-time jobs and commitments.

I would say we need to take a call to action to change this going forward.


How to revive the MicroView from GeekAmmo / SparkFun without solder.

Step one. Stay calm. The MicroView will work again…

IMG_6305 IMG_6300

If your like me, you have at least one other Arduino laying around to do this. Most any Arduino can be setup to be a programing tool.  Check out the whole tutorial on the Arduino website about what an ArduinoISP is and how it will save this guy from certain death.

There is good tutorial from Make on how to fix this, but in their write up they are soldering to the via pins, and I didn’t feel that is really necessary to do that.  So instead I used the wire from a really small resistor, and stuck that info the hole of the via pins, and was able to recover the MicroView.

Materials needed:

  • 1x Arduino Uno or Other Aurdino Uno board.
  • Bread board (came with your MicroView)
  • 5-7 Jumper wires
  • 3x Small hookup wire or small resistors to fit in the via holes
  • 3x Alligator clips or Mini grabbers <— These are important

Step one:

Open the front of the unit with your finger nail (no tools required!), it’s super easy to do. Just put a little pressure on the top and bottom, and use your finger nail on the sides to pull the front window out.

IMG_6257Step Two: Panic.

No wait. Stay calm. Gently lift the display to reveal the Via pins. Now put the MicroView into a bread board.



We are going to set this up using the method described in the Arduino Tutorial on making another Arduino an ISP programer.

  • Wire the Arduino GND to the GND rail on your bread board.
  • Wire 5V from the Arduino to the VIN pin of the MicroView
  • Put your jumper wires into the pins of the Arduino board for 10, 11, 12, and 13.
  • Wire Pin 10 from the Arduinio to the RST pin of the MicroView
  • Put a jumper from the BreadBoard GND to the MicroView GND – it should come alive and have the fun demo running.
  • Now comes the fun part… place the small wires into the Via holes like so…


For the wires, I used one side of a resistor leg, but you could also use small hookup wire. Grab your mini grabbers or alligator clips, and hook up the following:

  • Pin 11 of the Ardunio to Pin 11 of the MicroView
  • Pin 12 of the Arduino to Pin 12 of the Micro View
  • Pin 13 of the Arduino to Pin 13 of the Micro View

IMG_6288 IMG_6290

Now we need to turn your regular old Arduino into a programmer! Be careful of the wires, and go ahead and plug the Arduino in. To get this going, we are going to use the Arduino IDE completely! So if you’ve never used the command line tools, this will be easy for you.

First we need to open the Example Sketch “ArduinoISP”.

Screen Shot 2014-08-21 at 3.17.56 PM (2)

Screen Shot 2014-08-21 at 3.26.05 PM

Now select the Board type, and the serial port, and hit upload. Once this completes, we can set this up to be our ISP for programing the boot loader to the MicroView.

Burn The Bootloader

Reset the Arduino board, and set the Arduino IDE to use the “Arduino as ISP” to program for the MicroView.

Screen Shot 2014-08-21 at 3.37.57 PM (2)

Now, make sure all the wires are secure, and not shorting out, or crossing anything, select the serial port for the Arduino, and hit the “Burn Bootloader” menu option.

If everything works, it should only take about 5-10 seconds to write the boot loader to the MicroView. The MicroView will now go dark. This is normal, and expected, as we just wiped its memory.

You should then be able to unplug the wires and plug it back in your computers USB port, and program it directly via the USB board that came with the MicroView.

IMG_6294 IMG_6296 IMG_6298

Now put the front cover back on, and you are good to go!  Good luck, and I hope this helps are few people out!

Toorcamp Raspberry Pi Workshop!

I’m teaching a workshop at Toorcamp!

PiClassCrop26Do you want to make an automated cat feeder? Have you played with Ardunio or a Raspberry Pi? Maybe you’ve never used either. This workshop aims to teach the basic skills of setting up a Raspberry Pi Linux computer and working with Input and Output (GPIO). Using a Raspberry Pi and GPIO you can react and control the real world! We will teach you the skills you need to read temperature, light, control LEDs, move a servo (motor), and more!

This workshop will be split into two three-hour sessions. Part one will be installing and booting your Raspberry Pi, running python, and getting things going- ideally blinking LEDs by the end of class. Part two will involve advanced python concepts, and working on reading temperature, and other real world applications for GPIO.

To register visit:

The first class will start Friday July 11th, at 2:30pm.

Requirements for this class are:
A laptop or computer with a free USB port and Administrator or root access to the system.

This class has two tiers:
Tier 1 Includes a kit with a breadboard, sensors, LEDs, Wifi, etc. You must bring your own Raspberry Pi.
Tier 2 Comes with a Raspberry Pi, and includes everything from the kit in Tier1.

Tier 1 Workshop Kit Includes (
USB Cable
Serial Console Cable
SD Card
Pi Cobbler with Cable
Breadboarding wires
PiClassCrop31Cool Raspberry Pi Badge for your bag.
5 x 10K resistors for pullups on the buttons
5 x 560 ohm resistors for the LEDs
1 RED 10mm diffused LED
1 GREEN 10mm diffused LED
1 BLUE 10mm diffused LED
3 tactile pushbuttons
Light-sensitive resistor photocell
1uF capacitor
1 MCP3008 (Analog to Digital)
1 1-wire Temperature sensor
1 Analog Temperature sensor
1 USB Wifi

Tier 2 Workshop Kit:
Everything from the Tier 1 kit.
Raspberry Pi Model B

Tier 1 cost: $125
Tier 2 cost: $165

More power captain! Or when sprinkler valves fail…

For the Minnesota Roller Girls roller derby game in February they played in the Xcel Energy Center, which was awesome!  The place holds a ton of people, which is great for MNRG, but presents a challenge for the T-Shirt cannon, as the calculations were set for the Roy Wilkins Auditorium.  So, I went about changing the dimensions of the cannon to shoot T-Shirts twice as far!  Bassicly, I cut the accumulation chamber in half, added a 3″ PVC T, and 13″ more of 3″ PVC pipe.  This allowed us to get the force to shoot further, but also meant that we would only get two shots out of it. Continue reading

MNRG Raspberry Pi powered T-Shirt Cannon

Photo of MNRG T-Shirt Launcher

Wet Spot 2.0 Holding the Minnesota RollerGrils T-Shirt Cannon 2.0

Last year I was asked to repair the Minnesota RollerGirls T-Shirt Cannon that failed mid-season.  I created a temporary fix, just in time before the game. The repair got us talking about the future of T-Shirt launching technology. What would make this cooler? How can we improve this technology to make Launcher 2.0?

Minnesota RollerGirls’ Wet Spot (Lucas Saugen) and I started brain storming.  We met for lunch and started throwing around ideas.

What could we do better? In five years, where will the technology of T-Shirt launching be?  How can we make sure that there wouldn’t be a T-Shirt Cannon technology gap at the Minnesota RollerGirls?

Also, how can we make it so that the darn thing doesn’t break every season.

T-Shirt Cannon of past.

Former Cannon, mid fix on the operating table

This blog post details some of the build, process, and technology that went into making the new Raspberry Pi powered T-Shirt Cannon for the awesome Minnesota RollerGirls team!

First we came up with a list of things that we wanted for the new T-Shirt Cannon. This would ensure it would be a viable technology for future games and entertainment.

Our Ideas:

  • Tweet – (Yes, Tweet when it has launched a T-Shirt)
  • Camera – To capture that special moment of hitting someone in the face.
  • “Capture all the stats!” Tweet the stats about the launch
  • Launch more than one shirt in a time-out period, which is ~60-90 seconds.

We also got ideas from the teams:

Raspberry Pi Power Cat Feeder – Updates

Back in February 2013 I started teaching my Raspberry Pi 101 class. After the first class I think I had Pi on the brain, I was scheduled for a quick weekend trip out of town with my girlfriend, and she was due to leave her two cats behind. She said that she was going to leave a large bowl of cat food out, and with that I suggested that I build an automated cat feeder for them.


Ya know, so the cats don’t over eat, and maybe have a mixture of food, and it’s super cool! (Did I mention that it’s cool!?) So… five days before leaving town, I purchased the food hopper, and very quickly ran out of time to complete the project before leaving on vacation. So plan B it was, a large bowl of cat food, and water.

However, I did stick with my original plan, and saw the build to completion well before my next trip out of town. In this blog post, I’ll list out the step-by-step (for the most part) process to building your very own Wifi Enabled Raspberry Pi Powered Cat/Human Feeder.

Continue reading