Learn ARM Assembly With The Raspberry Pi

September 20, 2018 by Al Williams 41 Comments

We live in a time when you don’t have to know assembly language to successfully work with embedded computers. The typical processor these days has resources that would shame early PCs and some of the larger ones are getting close to what was a powerful desktop machine only a few years ago. Even so, there are some cases where you really want to use assembly language. Maybe you need more speed. Or maybe you need very precise control over timing. Maybe you just like the challenge. [Robert G. Plantz] from Sonoma State University has an excellent book online titled “Introduction to Computer Organization: ARM Assembly Langauge Using the Raspberry Pi.” If you are interested in serious ARM assembly language, you really need to check out this book.

If you are more interested in x86-64 assembly and Linux [Plantz] has you covered there, too. Both books are free to read on the Internet, and you can pick up a printed version of the Linux book for a small payment if you want.

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Learn To Loop The Python Way: Iterators And Generators Explained

September 19, 2018 by Ben James 17 Comments

If you’ve ever written any Python at all, the chances are you’ve used iterators without even realising it. Writing your own and using them in your programs can provide significant performance improvements, particularly when handling large datasets or running in an environment with limited resources. They can also make your code more elegant and give you “Pythonic” bragging rights.

Here we’ll walk through the details and show you how to roll your own, illustrating along the way just why they’re useful.

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Easy Portable Serial Ports

September 14, 2018 by Al Williams 51 Comments

Modern operating systems insulate us — as programmers, especially — from so much work. Depending on how far back you go, programmers had to manage their own fonts, their own allocation space on mass storage, or even their own memory allotments. Every year, though, it seems like things get easier and easier. So why is it so annoying to open a simple serial port? It isn’t hard, of course, but on every operating system it seems to be painful — probably in an attempt to be flexible. And it is even worse if you want portability. I needed to write some C code that read data from an FPGA’s embedded logic analyzer, and I was annoyed at having to write yet more serial port code. I have my own shim library, but it isn’t well tested and isn’t all that flexible — it does what I need, but I wanted something better. What I wound up with the serial library from Sigrok. You know Sigrok? The logic analyzer software.

You might counter that the serial port is old hat, so no one wants to support it with modern systems. While the physical serial port might be on life support, there’s no shortage of equipment that connects via USB that appears to be a serial port. So while I was talking to an FTDI chip on an FPGA board, you could just as well be talking to an Arduino or a USB voltmeter or anything.

I guess the Sigrok developers had the same problem I did and they took the time to write a nice API and port it to major platforms. Although Sigrok uses it, they maintain it as a separate project and it was just what I needed. Sort of. I say sort of because the version installed with Ubuntu was old and I needed some features on the newest release, but — as usual — the Internet came to the rescue. A quick Git command, and four lines of build instructions and we were ready to go.

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A Whole Other Kind Of Graphical Programming

September 13, 2018 by Sven Gregori 31 Comments

Java isn’t everyone’s cup of tea. With all its boilerplate and overhead, you’re almost always better off with a proper IDE that handles everything under the hood for you. However, if you learn a new language, you don’t really want to be bothered setting up a clunky and complex IDE. If only you could use a simple, standard Windows program that you are most likely already familiar with. This wish led [RubbaBoy] to create the MSPaintIDE, a Java development environment that let’s you write your code in — yes — MS Paint.

If you’re thinking now that you will end up writing your program with MS Paint’s text tool and create a regular image file from it — then you are right. Once set up, MSPaintIDE will compile all your PNG source files into a regular Java JAR file. And yes, it has syntax highlighting and a dark theme. [RubbaBoy] uses a custom-made OCR to transform the image content into text files and wraps it all into few-button-click environment — including git integration. You can see a demonstration of it in the video after the break, and find the source code on GitHub.

One has to truly admire how far [RubbaBoy] went, considering the tongue-in-cheek nature of this project. And all joking aside, if you’re interested in OCR, this might just be simple enough to begin with. Or you could expand it with some text to speech functionality.
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Pun Intended: Bare Metal Attracts Rust

September 8, 2018 by Sven Gregori 36 Comments

Programming languages tend to polarize, and Rust is by far no exception. Whether it will stick around and grow as an alternative for the lower levels or not — time will tell. In the meantime, if you’re curious about the language and its low-level abilities yourself, [phil-opp] has written a series of blog posts on building your own little bare metal kernel in Rust.

Starting from the basics, [phil-opp] describes in detail the set-up and build process to create a standalone executable that won’t be linked against the Rust standard library. From here he proceeds to build a simple operating system kernel that prints a good old Hello World via VGA output — QEMU emulation included. And of course, there is a GitHub repository with all of the source code.

[phil-opp] has been working on this for a while already, and he is currently writing the second edition of the series. Some content is therefore still missing, but you may find more of it in his first edition. And in case you know absolutely nothing about Rust in the first place, let’s just take a step back and start with the basics. After all, we might see more of it in the future.

FOSSCON 2018: Where Open Source And LEGO Collide

September 7, 2018 by Tom Nardi 10 Comments

It probably won’t come as a surprise to anyone reading this, but hackers and makers absolutely love LEGO. We think you’d be hard pressed to find a Hackaday reader, young or old, that hasn’t spent some quality time with the little plastic bricks from Billund, Denmark. So it follows that there’s a considerable community of individuals who leverage their better than average technical prowess to utilize LEGO in new and unique ways. But the activities and history of these LEGO hackers is not exactly common knowledge to those who aren’t heavily vested in the hobby.

During the recent FOSSCON 2018 in Philadelphia, Daniel Pikora gave attendees a comprehensive look at the intersection of open source development and the world’s most popular brand of construction toys. A software developer with a penchant for open source code by trade, he’s also an avid member of what’s known as the Adult Fan of LEGO (AFOL) community who’s exhibited his creations at shows across the United States and Canada. Such a unique perspective, with a foot in both the FOSS and LEGO camps, makes Daniel an ideal tour guide for this particular microcosm of toys and tech.

In a whirlwind presentation that took attendees through 49 slides in about as many minutes, Daniel covered LEGO’s beginnings in the 1930s to the rise of 3D printed custom bricks, and everything in between. Some of the engineering-centric product lines, such as Technic and Mindstorms, were already fairly well known to the types of folk who spent a beautiful Saturday in Philadelphia at an open source conference. But Daniel’s deep-dive into the long history of open source LEGO projects brought to light the work of so many dedicated developers that everyone walked away with a newfound respect for the amount of work the AFOL community has put into elevating LEGO from a child’s toy to a legitimate tool. Join me below for a look at the particulars of that deep dive.

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Intro To Docker: Why And How To Use Containers On Any System

September 5, 2018 by Ben James 72 Comments

If you have your ear even slightly to the ground of the software community, you’ll have heard of Docker. Having recently enjoyed a tremendous rise in popularity, it continues to attract users at a rapid pace, including many global firms whose infrastructure depends on it. Part of Docker’s rise to fame can be attributed to its users becoming instant fans with evangelical tendencies.

But what’s behind the popularity, and how does it work? Let’s go through a conceptual introduction and then explore Docker with a bit of hands-on playing around.

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