Embedded

Chris (@stoneymonster) and Elecia (@logicalelegance) talk about design patterns, conferences, and Molotov cocktails. Wrapper /  Decorator  / Facade Observer aka subscriber/publisher (caveat) Delegation and Dependency Injection Model View Controller (very important if somewhat dated UI pattern) PyFlakes is a static Python checker KiCAD Conference is in Chicago on April 26-27, 2019 BangBangConWest 2019 is over but the videos will be up soon including the one Elecia noted about liking things (which was done by Lynn Cyrin). Embedded.fm Patreon

Valve's Alan Yates (@vk2zay) spoke with us about the science and technology of virtual reality.  Elecia looked at the iFixIt Teardown of the HTC Vive system as she was unwilling to take apart Christopher's system.  Alan shared some of his other favorite reverse engineering efforts: Doc OK’s Lighthouse videos, documentation on github by nairol, and a blog by Trammell Hudson. Alan's sensor circuit diagrams were on twitter: SparkleTree sensor circuit (think simplified) and the closer-to-production Lighthouse sensor. Make Magazine talked about Valve's R&D Lab. This is important in case you want to work at Valve (they are currently hiring for EE but if that doesn't describe you and you want to work there, apply anyway). Alan also has a website (vk2zay.net) though it doesn't see much updating right now.  

Patrick Yeon (@patyeon) spoke with us about nonprofit spaceships then asked our opinions about embedded software. Pat is working for something something nonprofit space something something. To fill in some of the blanks, apply for a job on NonprofitSpaceship.org. Pat was previously on episode 153: Space Nerf Gun when we talked about cost-optimized satellites. We talked about several books: Turn the Ship Around! A True Story of Turning Followers into Leaders by L. David Marquet Managers Path: Leaders Navigating Growth and Change by Camille Fournier Design Patterns: Elements of Reusable Object-Oriented Software by Erich Gamma, Richard Helm, Ralph Johnson, and John Vlissides Head First Design Patterns: A Brain-Friendly Guide by Eric Freeman, Elisabeth Robson, Bert Bates, Kathy Sierra Elecia’s command code is on github.  

Matthew Liberty (@mliberty1) shared good advice for lowering power. We talk about different ways to measure current (Matt has a nice write-up) and things software can do to decrease power consumption. Sleeping is critical, of course, as is choosing your clock speed and setting the GPIOs to good states. Everything is fine until you start getting into the microamps, then your multimeter measurements may start to fail you. (EEvblog explains why in his uCurrent intro.) Eventually, you may want to measure nanoamp sleep states along with amp-consuming wake states. Matt’s Joulescope is a tool to do just that (Kickstarter goes live Feb 19, 2019!), automatically moving between 9 orders of magnitude of dynamic range and graphing the results on your computer. Matthew’s consulting company is JetPerch. We mentioned Colin O’Flynn’s ChipWhisperer which uses differential power analysis for security attacks. We also talked about Jacob Beningo’s post on protecting your tools. Elecia is giving away a chapter of her O’Reilly book, Making Embedded Systems. It is Chapter 10: Reducing Power Consumption. Hit the contact link if you want a copy.

Jie Qi (@qijie) spoke with us about making paper-based electronics (@Chibitronics) and learning about patent law (via @Patentpandas). Jie Qi is the founder of Chibitronics, a crafting electronics platform that uses paper and stickers to create (and teach) circuits. Building the company and working on electronics-filled pop-up books led to the realization that patent law does apply to open source maker-type companies. She started PatentPandas.org to share what she’s learned. Jie is not the only one who has had issues with big companies patenting their open source work. We mentioned Jarek Duda and his fight to keep his compression algorithm unburdened by patents. If you are having or wondering about having an issue, Patent Pandas is intended to be an amusing and gentle introduction. If you are looking for prior art, you can look at the Prior Art Archive and Patents.StackExchange. (If you have some free time, there are often requests to find prior art.) If you are a maker wanting to ensure that your work has dated prior art, submit it to the Wayback machine (Archive.org).

Jesse Rutherford (@BentTronics) gave us an in-depth look at the 555 timer IC (wiki). Jesse runs Bent-tronics.com and wrote The Ultimate Beginner's Guide to the 555 Timer (Amazon). Some great 555 projects: 555 Decimal Adding Machine 555 found in a drill trigger speed controller as seen on the Ben Heck Show 555 found inside a solar charger controller, video by Julian Ilett Somehow, despite it being in the plan, we didn’t mention the Evil Mad Scientist The Three Fives Kit: A Discrete 555 Timer which builds a 555 Timer out of discrete parts. If only the creator would come on to talk about it and his other cool projects. Note that EMS also has a great description of how the 555 timer works. The giveaway is Jesse’s book and the components to build the projects in his book.

Janelle Shane (@JanelleCShane) shared truly weird responses from AIs. Her website is AIWeirdness.com where you can find machine-learning-generated ideas for paint colors, ice cream, and cocktails (and many other things). We never said they were good ideas. Janelle’s FAQ will help you get started trying out RNNs yourself. We recommend the Embedded show titles. We talked about BigGAN which generates pictures based on input images. Wikipedia list of animals by number of neurons Janelle’s upcoming book is You Look Like a Thing and I Love You. Sign up for her newsletter to be the first to order it (as well as getting the PG-13 versions of her hilarious AI outputs).

Ivan Kravets (@ikravets)  spoke with us about PlatformIO (@PlatformIO_Org), IDEs, embedded libraries, and RISC-V. PlatformIO is an editor, an integrated development environment with debugging and unit testing, and/or a library index. Its goal is to make embedded development easier and more consistent across host operating systems and development hardware. It is also a .org because the goal is to make all of this open source and free to engineers. Ivan Kravets is the founder of PlatformIO.org. Personal site, Github, LinkedIn, and a neat interview. He recommends seeing the Dnieper River if you are in his area. Ivan recently attended the RISC-V Summit. RISC-V is an open source processor core (like ARM but open source). SiFive was mentioned as one of the RISC-V processor vendors. RISC-V is being used extensively in research. Western Digital is planning to develop RISC-V based controllers. And MIPS recently joined RISC-V.

Chris and Elecia chat with each other about the new year. All is fine until she starts quizzing him about some language details of his new project. Many object-oriented resources suggest using composition (has-a) over inheritance (is-a-type-of) (wiki). Where do swift extensions fit in? It seems to me (Elecia here) that extension is invisible composition that allows adding of functions. For example, say you want a TiltSensor and you already have an ImuSensor object so  you need to add a function for TiltComputation. You could make the TiltSensor contain an ImuSensor (composition). You call the ImuSensor functions to check the readings when running TiltComputation function. You don’t need to know what is in ImuSensor, only what the API is. You could have TiltSensor be a child class of ImuSensor (inheritance) so that TiltSensor responds to all ImuSensor functions as well as its new TiltComputation function. You could use the variables in ImuSensor directly for TiltCompulation but you will need to know what is in ImuSensor for that to work. Or, in Swift, you could have TiltSensor be an extension of ImuSensor. Except it wouldn’t be called TiltSensor, it would be part of ImuSensor: any file that had access to your extensions would be able to create an ImuSensor instance and call TiltComputation as if it was part of the original ImuSensor API. The TiltComputation function would only have access to its extension’s variables and ImuSensor’s API. You get to add new functionality without breaking backward compatibility. Some more resources on this topic: Composing Types in Swift Swift Language Guide: Extensions Swift Programming: The Big Nerd Ranch Guide by Matthew Mathias and John Gallagher iOS Programming: The Big Nerd Ranch Guide by Christian Keur and Aaron Hillegass LinkedIn Learning Courses Blender Beta with EEVEE renderer The Clean Coder: A Code of Conduct for Professional Programmers by Robert C. Martin Code Complete: A Practical Handbook of Software Construction by Steve McConnell Gelly Roll Glitter Pens (by Sakura) Google Podcast Link (or see the Subscribe page)

Chris Gammell (@Chris_Gammell) of The Amp Hour (@TheAmpHour) joined us to talk about the state of the industry, listeners, guests, and life in general. Embedded’s accounting episode (150: Sad Country Song) Contextual Electronics Consulting forum (requires you to apply) Remote work 250: Yolo Snarf Excellent video on how prototype PCBs have improved over the years Quickly falling cost of dev boards Elecia worked on learning and building robots and happily got a related job Chris W is building IOS apps Object oriented Prototype to Product: A Practical Guide for Getting to Market by Alan Cohen (Emebdded.fm interview) CircuitPython Visual Basic as a prototyping language ESP32 and EXP8266 longevity and use in products WiFi provisioning Electric Imp, Particle.io Azure IoT Hub, AWS IoT, Google Cloud Iot, Ubidots, and IoT App Story (the one Chris G remembered later) Wallet.fail Anki Vector robot Genuine People Personality (from Hitchhiker's Guide to the Galaxy) Genuine people personalities are coming to our gadgets (ArsTechnica) LoRA and chuckable sensors LoRaWAN and ARM Mbed OS Telepresence and mirroring others The Amp Hour ToorCamp episodes Sourdough (a novel about robotics and AI) and Embedded’s interview with the author Energy and Civilization: A History by Vaclav Smil Jeri Ellsworth spoke about the demise of CarstAR in The Amp Hour 394 The Stone Monsters music products Llama and the IoT zines Related Oatmeal comic Supporting Embedded Patreon leads to a link to their slack channel, mentioned in this show. Supporting The Amp Hour Patreon is also a great idea.