Teaching Alexa To 3D Print

January 5, 2018 by Al Williams 21 Comments

Sometimes a gadget like Alexa or Google Home is a solution looking for a problem. Then the problem you’ve been looking for hits you square in the face. I’ve confessed before that I have an oscilloscope problem. I also have a microcontroller development board habit. It appears now I have too many 3D printers. I recently finished building my latest one, an Anet A8 I picked up on Black Friday. While calibrating it, I found myself juggling a screwdriver, a pair of pliers, and trying to operate the thing all at one time. I realized I had to come up with a better way.

I don’t know if it qualifies as an addiction yet, but I also have an Alexa in every room (although I call it “Computer” because I’m a Star Trek fan) and a Google Home device almost everywhere. Why can’t I get one of these assistants to operate my printer for me? What are assistants for, after all, other than telling Dad jokes?

You’d think adding voice control to a 3D printer would a bit difficult. With the right tools, it is actually pretty easy. Luckily those tools aren’t anything special… if you want a set up like mine, where Alexa controls your 3D printer, read on.

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TRS-80 Model 100 Goes Cellular

January 4, 2018 by Al Williams 10 Comments

There are a few old products that have rabid fan bases, and the TRS-80 Model 100 is one of those. Depending on your point of view it’s either a small laptop or a large organizer, but in 1983 it was the ultimate computer on the go. The $1100 version had a whopping 8K of memory and the LCD screen showed 8 lines of 40 characters in glorious monochrome. One cool feature was the built-in 300 baud phone modem, which [Trammell Hudson] wanted to try, but he doesn’t have a landline. He tried a VOiP phone, but it wouldn’t wedge into the acoustic couplers well enough. Then he decided to go cellular.

He had already hooked up an old ITT 500 series dial phone to an Adafruit Fona ceullar board. He even has Teensy software to decode the dial, drive the dial tone and otherwise make the phone work. This time he hooked a handset up through a headset jack.

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Hack Your Own Computer Science Degree

January 4, 2018 by Al Williams 38 Comments

We ran across something interesting on GitHub of all places. The “Open Source Society University” has a list of resources to use if you want to teach yourself computer science for free. We found it interesting because there are so many resources available it can be hard to pick and choose. Of course, you can always pick a track from one school, but it was interesting to see what [Eric Douglas] and contributors thought would be a good foundation.

If you dig down, there are really a few potential benefits from going to college. One is you might learn something — although we’ve found that isn’t always a given, surprisingly. The second is you can get a piece of paper to frame that impresses most people, especially those that want to hire you but can’t determine if you know what you are talking about or not. Lastly, if you go to the right school you can meet people that might be useful to know in the future for different reasons.

The Internet has really changed all of those things, you can network pretty easily these days without a class ring, and there are lots of ways to earn accredited diplomas online. If you are interested in what we think is the most important part — the education — there are many options for that too.

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The Grooviest Random Number Generator Ever

January 4, 2018 by Al Williams 28 Comments

Cloudflare is one of those Internet companies you use all the time, but don’t usually know it. Big websites you visit use Cloudflare to shore up their defenses against denial of service attacks. The company needed some truly random numbers for its security solutions, so it turned to some groovy old tech: lava lamps. In their office is a wall of 100 lava lamps monitored by cameras. The reaction of the lamps is unpredictable, and this allows them to generate really random numbers. [Joshua], a Cloudflare employee, talks about the technical details of the system in a recent blog post.

You might think this is a new and novel idea, but it turns out the LavaRnd (or maybe it is LavaRand — there’s some dispute if you read the comments below) system has been around for a while. In fact, we covered it way back in 2005. Silicon Graphics patented the system in 1996.

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Making Solar Cells

January 4, 2018 by Al Williams 11 Comments

We will admit that it is unlikely you have enough gear in your basement to make a solar cell using these steps. However, it is interesting to see how a bare silicon wafer becomes a solar cell. If you’ve seen ICs going through fabrication, you’ll see a lot of similarities, but there are some differences.

The process calls for a silicon wafer, some ovens, spin coaters, photolithography equipment, and a dice saw, among other things. Oh, you probably also need a clean room. Maybe you should just buy your solar cells off the shelf, but it is still interesting to see how they are made.

Modern solar cells have some extra structures to improve their efficiency, but the cells in this video are pretty garden-variety. For example, some experimental cells use multiple layers of active devices, each tuned to absorb a different wavelength of light.

If you really want to make your own, there’s another process where you can start with some copper and wind up with a kind of solar cell that uses a copper-based semiconductor material. But don’t be fooled into thinking that making the silicon variety is totally out of reach to hackers, we’ve seen [Sam Zeloof] pull it off.

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Tips On Building The BlackIce BBC Micro

January 3, 2018 by Al Williams 4 Comments

You can look at pictures and video of the Grand Canyon, Paris, New York City or anywhere else, and yet when you finally see those places with your own eyes it is somehow different. Fielding an old computer like the BBC Micro on an FPGA has been done before. But there’s always something to learn when you do it yourself. [Machina] took a BlackIce board and made a BBC Micro replica, but he learned a few things along the way and decided to share them for our benefit.

He used the BlackIce board with [Dave’s] BBC Micro implementation that we’ve covered before. [Machina] was impressed that the board takes PMOD plug ins, so it was easy — almost — to add a VGA and keyboard port. Although both gave him some unexpected problems.

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Much Assembly Required: Game Your Way To Assembly Guru Status

January 1, 2018 by Al Williams 18 Comments

It can be hard these days to find an excuse to create something for learning purposes. Want a microcontroller board? Why make one when you can buy an Arduino or a Blue Pill for nearly nothing? Want to control a 3D printer? Why write the code when you can just download something that works well like Marlin or Repetier? If you want to learn assembly language, then, it can be hard to figure out something you want to do that isn’t so silly that it demotivates you. If that sounds like you, then you should check out Much Assembly Required.

This is a multi-player game that runs in your Web browser. But before you click close, consider this: the game has you control an autonomous robot using an x86-like assembly language. Your robots have to find resources and build structures so it is sort of a mash up of Minecraft and one of the many modern Hammurabi-inspired games like Civilization.

The robots have a variety of peripherals including: drills, lasers, LiDar, legs, a hologram projector, solar-charged batteries, clocks, and more mundane things such as clocks, floppy drives, and a random number generator. The virtual world simulates day and night, so plan your power management accordingly.

You might wonder if you should even bother learning assembly. While it is true it isn’t as necessary as it once was, understanding what the computer is doing in a very basic way can help form your thinking in surprising ways. There are also those times when you need to optimize something in assembly and that’s the difference between working and not working.

If you want to do something more practical, we’ve looked at options before. Of course, you can always slip your C compiler some assembly, too.