Embedded Computing Design

There’s a manufacturing parable which tells of a person who can’t sharpen his axe because he’s too busy cutting down trees. The point being that you must invest some time/money into your means of production, even if it’s difficult in the short term.

Nearly 2 years ago, I wrote an article about my favorite useful designs for 3D-printing. As it just so happens, I recently put out a time-lapse video of my last 2 years of 3D-printing. While there were a few decorative items thrown in, the vast majority of my printing efforts involved useful implements, so I think it’s time for an update!

When I was first introduced to KiCad, routing traces was described as a bit of an art, something to be learned from experience. I’d say that is true, however, in addition to my first quick tips article, here are some additional–perhaps more strategic–techniques that I can offer to those getting started.

Throughout the last year-plus, I’ve written a number of articles outlining my experience with KiCad. It’s an incredible open-source EDA package, and what I consider my first and best piece of advice for those getting started is to go ahead and order your first PCB when it seems workable. It may not be perfect, but you’ll certainly be able to improve things on the next run.

I’ve been a member of the Tampa Hackerspace (THS) organization for several years. It’s been an important resource for me, and the connections I’ve made there have been valuable on many occasions. If you’ve been on the fence about joining such a space, I’d encourage you to do so. If you need a little push, or if you’re not sure about the whole concept, read on!

Almost 2 years ago, I met Paul Stoffregen, creator of the Teensy line of dev boards, at the 2019 Hackaday Superconference. Besides being pleased to meet a well known hardware innovator, I was also happy that he presented me with a sample of his Teensy 4.0 board–from a custom leather swag holder, no less.

KiCad is an incredible open source EDA package that I’ve been using since early 2020. Being able to design your own PCBs is quite useful, and I find the design process to be a lot of fun.

As I write this, I’ve successfully crowdfunded my JC Pro Macro 2 (JCPM2) mechanical keypad on Kickstarter. I’m extremely proud of this computer interface device, and when this article is published you should still have a few days to get one yourself. It’s an expanded version of the mini keyboard and rotary controller, with the addition of more LED lighting, and additional GPIO breakout features.

When the original Raspberry Pi was released in 2012, it caused quite the stir, selling out in hours. Several years later, in 2015, Raspberry Pi released the scaled down Raspberry Pi Zero, which featured similar specs to the original, but at a mer $5 price tag–and was even included on the cover of their MagPi magazine. A WiFi-enabled ‘Zero was released in early 2017, further enhancing its capabilities.

EDA packages like KiCad, and the design of electrical circuits in general, are normally thought of as a 2D affair.

I²C also often spelled I2C, and (rarely) expanded out to its full “Inter-Integrated Circuit” moniker, is a device-to-device communication protocol invented by Philips Semiconductor (now NXP) in 1982.

Castellated holes on a PCB, also known as castellations or crenellations, are plated through holes on a PCB which are cut in half. Typically, these are applied to the outer edges of a board, and are used to solder one board on top of another.

Computing, in the sense of storing, routing, and manipulating data is, of course, a vast and interesting subject. At the end of the day however, I’d argue that one has to actually use this information for it to be useful. While this can mean providing information to humanity, in other cases the computer itself is tasked with manipulating our world directly through a variety of actuators and electro-mechanical apparatuses.

When it comes to tiny microcontroller development boards, there are a number of great options. I’m personally a big fan of the ATmega32U4-based Arduino Pro Micro which, among other functions, can emulate computer keyboard/mouse inputs as a human interface device (HID).

Most computer users interact with their device using a keyboard and mouse. Some of us have switched to a trackball-style input and/or a new keyboard better suited to one’s body style or use, but at the end of the day, what you normally buy online or from a brick-and-mortar store is designed to suit a large number of users. 

In a previous post, I outlined how you can manage and customize new symbols in KiCad, allowing you to accurately depict your circuit designs.

Jeremy shows an easy and fun way to create symbols in new libraires using KiCad.

When you purchase a PC fan for standard usage, it comes with a nice plug-in wiring harness that you simply connect to let it do its job... or so I assume.

If you have browsed online auction sites and/or various small electronics projects to any extent, there’s a good chance you have come across a .96” 128x64 pixel OLED display, based on the SSD1306 driver.

I now primarily work as a sort of tech journalist–documenting interesting projects and technology, while building a variety of projects that I can write about and sometimes sell. Before that, I spent well over a decade as an engineer working in manufacturing automation. In this arena, as in life, the universe, and everything, there comes a point where a “thing” works more or less as it did yesterday, but in a state that could be improved.