Erik L. Arneson — Writer and Software Developer

Slides on a Stick with Raspberry Pi Zero W

2017-10-15T19:38:19+00:00

If you give presentations often, you will know that one of the biggest headaches is managing slides. You have to figure out software, hardware, and connectors. I’ve usually resorted to bringing a USB thumb drive with my slides in PDF and ODP format, but then I came across an even better idea: the Raspberry Pi Zero W (or RPi0W).

Previously, I had been playing with using Erlang on the RPi0W to control stepper motors, but this seemed more useful. Follow along to see how I created a portable presentation machine that’s about the size of a pack of gum.

Hardware Used

I purchased the RPi0W as part of a kit so it would have a nice case and all of the connectors I needed. I also wanted a good way to control it, so I found an inexpensive mini wireless keyboard and mouse on Amazon. You can follow my example or find your own alternatives.

Installing and Configuring Software

I’m not the first person to think of using a Raspberry Pi for slides and presentations. Rob Reilly wrote a great article on this topic for Raspberry Pi Geek which provides some great tips and recommendations. However, I wanted to create a presentation machine that was even faster and more portable.

I used Raspbian Stretch with Desktop, but knew that I would run into memory and performance issues on the RPi0W. It only has 512MB of RAM, so I would need to use small, efficient applications and cut out unnecessary services and applications on the device. It’s really important that the machine boots up fast and gets running quickly.

Quickly I gave up on the idea of running LibreOffice Impress. Instead, I would use a lightweight full-screen PDF viewer. I tested out a number of the smaller PDF readers available on Raspbian before finally settling on apvlv. This reader is tiny, fast, and configurable. It also requires some additional setup.

Install apvlv on your system with the following commands.

sudo apt update && sudo apt upgrade -y
sudo apt install -y apvlv

These commands might take a while. When you are done, edit the apvlv preferences file. You will probably do this using the command nano ~/.apvlvrc but you might want a different text editor. Edit to look like this.

set fullscreen = yes
set zoom = fitwidth
set continuous = no
set scrollbar = no
set content = no

Displaying Slides

You will need to get your PDF slides onto the RPi0W. I usually use a webpage to download them, or copy them over via scp. Do whatever feels best to you.

Simply use the apvlv command from a terminal or the menu to load your PDF file. The interface is a little arcane, but easy to get the hang of. You can use the up and down arrows on the mini keyboard to go forward and backward one slide. To exit, hit q and to go to a specific slide type :go <number> and replace “<number>” with the slide number.

The RPi0W still takes a little while to boot, but you now have an extremely portable device that plugs into any HDMI screen or projector and displays your slides with as little fuss as possible!

Driftwood Public Library Follow-Up

2017-05-01T17:27:58+00:00

Driftwood Public Library is great! I had a wonderful time in Lincoln City speaking about secret societies and cryptography. Links to my slides are below.

Secret Societies in Fiction How Computers Changed Cryptography

For a bibliography for “How Computers Changed Cryptography”, check my notes for my OMSI Science on Screen talk.

Also, I would like to thank the ‘D’ Sands Condominium Motel for sponsoring the talks and providing me with a really lovely room.

[caption id=”attachment_708” align=”aligncenter” width=”1024”] This is the view from my motel room balcony at the ‘D’ Sands.[/caption]

Upcoming Lectures at Driftwood Public Library

2017-04-13T17:04:39+00:00

Driftwood Public Library in Lincoln City has selected Mr. Penumbra’s 24-hour Bookstore for their 2017 Everybody Reads event. They’ve invited me to give two lectures. This is going to be fun!

Secret Societies in Fiction

Tuesday, April 25, 6:30pm

This is going to be a lecture about secret societies. I’m going to talk about what a secret society is, and then we’ll look at how they’re portrayed in fiction. We will also talk about how fictional secret societies have sometimes become real secret societies, and the relationship between secrecy and fiction in the real world.

How Computers Changed Cryptography

Wednesday, April 26, 2:00pm

If you saw my OMSI talk, then you already know that this is a subject I’m passionate about! I will be discussing the history of computers and how it’s intertwined with the cryptography arms race. Maybe I will even introduce some hand ciphers to the crowd! I am going to have fun with this one.

I am sure that more information on both of these will be available soon, including Facebook events and other such things. In the meantime, visit the Driftwood Public Library website for more information.

OMSI Science on Screen Wrapup

2017-03-29T16:51:34+00:00

My talk at OMSI last night, “Computers and the Dawn of Modern Cryptography,” went really well. It was a great crowd and there was a good Q&A session afterwards. I’m going to keep this post really brief. First, there will be slides for my talk. Following that will be a brief bibliography if you’re interested in learning more about this fascinating topic.

Click here to download my slides.

Bibliography

Singh, Simon. The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography. Reprint edition. New York: Anchor, 2000. This book is the best resource I've found for a logical breakdown of how cryptography and cryptanalysis worked for WWII cryptology.
Boone, J. V. A Brief History of Cryptology. Annapolis, Md: Naval Institute Press, 2005.
Copeland, B. Jack, ed. Colossus: The Secrets of Bletchley Park’s Codebreaking Computers. Oxford ; New York: Oxford University Press, 2006. I can't wait to explore this book more! It is a massive collection of articles and papers from a wide array of authors.
Drea, Edward J. MacArthur’s ULTRA: Codebreaking and the War against Japan, 1942-1945. Modern War Studies. Lawrence, Kan: University Press of Kansas, 1992.
Wilcox, Jennifer, United States, National Security Agency/Central Security Service, and Center for Cryptologic History. Sharing the Burden: Women in Cryptology during World War II. Fort George G. Meade, Md.: Center for Cryptologic History, National Security Agency, 1998.

In addition, almost all of the photos and information on individual cipher machines can be found at Crypto Museum. This is a rich and bountiful resource for those interested in the internal workings of modern encryption.

OMSI Science on Screen: The Imitation Game

2017-03-17T20:17:00+00:00

On March 28th, I will be giving a lecture called “Computers and the Dawn of Modern Cryptography” at OMSI as part of their Science on Screen program. I’ll be speaking and answering questions just before a screening of The Imitation Game, starring Benedict Cumberbatch and Keira Knightley. I am really excited about this opportunity! Please come down to OMSI for an informative lecture and an excellent film.

Buy Tickets Here

A Look Back on the History of Cryptography

2015-06-01T15:30:02+00:00

In May, I taught a class on the History of Cryptography at Portland Underground Grad School. I’m extremely grateful to PUGS for asking me to teach, because I’d never done it before. It was a great experience. My students were intelligent and the discussion was good. I learned quite a few things in the process.

Teaching Isn't the Same as Lecturing

I have a lot of experience with public speaking. I spent time in Toastmasters International and have given many lectures. In fact, here’s a video of me giving a lecture on the art of memory back in 2013. (( I embedded this video just to exploit a neat WordPress feature. ))

https://www.youtube.com/watch?v=-WpxbPHkq4A

I knew that teaching would be different, but I didn’t know what to expect. Luckily, Douglas Tsoi, the mastermind behind PUGS, helped me design my four-week curriculum and gave me a lot of advice. The two main differences that I noticed are that, first, teaching is a lot more like a conversation, and second, you continue following up week after week. Conversation and continuity!

Douglas’s help was invaluable. He’s the reason that PUGS is able to bring in experts without teaching experience while providing a rich educational environment.

It's Hard to Boil Down Experience

"There is so much to learn! I enjoyed being able to ask questions at will and go deeper into the subject with a knowledgeable instructor." -- An anonymous student

A PUGS class lasts four weeks, and there’s only one class per week. That’s not a lot of time to cover a complicated subject. Going into the class, I just didn’t realize how difficult it is to cram decades of experience into just a few weeks. In our third class, while discussing Phil Zimmerman and the creation of PGP, I realized that I’d been learning about cryptography for over 20 years.

The learning curve in cryptography is staggering. I didn’t realize that going into it, but it’s really difficult to introduce things like the Diffie-Hellman key exchange protocol to people who had just learned to do an alphabetic substitution cipher for the first time. All of my students were very intelligent people, but none of them were computer scientists or mathematicians. My curriculum is going to take some adjustment.

Teaching is Fun

Through this class I met many interesting people. While preparing for the class, I had to brush up on a lot of dusty knowledge. In the process I learned a lot. The entire thing was mentally engaging, socially stimulating, and a blast. I hope that PUGS will have me again, because this class is only going to get better.

If you enjoy learning, you owe it to yourself to take a class at the Portland Underground Grad School. Go check them out!