It’s cold outside! So grab a copy of the Hackaday Podcast, and catch up on what you missed this week.
Highlights include a dip into audio processing with sox and FFMPEG, scripting for Gmail, weaving your own carbon fiber tubes, staring into the sharpest color CRT ever, and unlocking the secrets of cheap 433 MHz devices. Plus Elliot talks about his follies in building an igloo while Mike marvels at what’s coming out of passive RFID sensor research.
And what’s that strange noise at the end of the podcast?
Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
Chiptune is a musical genre built upon the creation of music through the use of chip-based sound synthesizers, found in early game consoles. The Commodore 64’s venerable SID chip and the Game Boy Sound System are the by far the most popular on the scene. However, the Sega Genesis took a different path at the end of the videogame chipmusic era, packing a YM2612 FM synthesis chip to deliver fat basslines and searing solos. [Thea] has always been a fan of these electric 90s sounds, and thus decided to build the Genesynth.
The synth initially allowed only for playback of existing video game scores, but its capability has been expanded as [Thea] took the project from breadboard to protoboard to custom PCBs – with anime artwork, to boot. The synth uses a Teensy 3.5 as the brains, speaking USB to enable the synth to receive MIDI commands from music software. All parameters are exposed over the interface, and [Thea] has several videos showing the Genesynth under control from an Ableton Push.
The sound capabilities of the YM2612 are of an entirely different character to most chiptunes, by virtue of the FM synthesis engine. FM synthesis is a little less intuitive then classical additive synthesis, but we still see it crop up now and then.
Recently, I was lucky enough to receive a big haul of retro computer gear from a friend who was emptying out his garage. Even better, the haul was almost entirely old Amiga gear — my favorite computing platform of all time. Upon returning home, I gleefully sorted through the boxes, powering things up one by one. Amazingly, everything worked… except for one lonely Amiga 500+. I was greeted by a dull grey screen. This wouldn’t do, so naturally, I got to work.
It seemed like a shame to be opening the machine, as after almost 30 years of life, this one still had its warranty seal intact. Regardless, nothing ventured, nothing gained – the Torx bits were at hand and the screws were coming out.
Handheld consoles have to make a lot of design choices that their TV connected brethren don’t have to worry about. Battery life is important, as is screen visibility, and the games can’t be too bulky or unwieldy if you’re going to be carrying them around all day. [Chris] is no stranger to building handheld versions of home consoles, and took a few of these lessons on board in his latest portable SNES build.
The motherboard was provided by a SNES Jr., a lightweight, compact model released towards the end of the console’s reign. This was small enough that it required no trimming, however [Chris] elected to replace the inefficient 7805 with a more modern switching regulator. The case was 3D printed on a typical FDM setup, while the buttons were produced on a Form 2 for better dimensional accuracy and surface finish.
The flash cart PCB is permanently wired to the motherboard.
The real party piece, however, is the use of an SD2SNES flash cart. This allows a huge variety of ROMs to be loaded onto a single SD card, and played on the original console hardware. This is particularly useful in a portable build, as it becomes possible to carry all the games you could want, rather than having to juggle several full-sized SNES cartridges. The SD2SNES is wired in place permanently inside the console, with an impressive number of patch wires between the motherboard and the cartridge PCB. Despite the long lead length, [Chris] reports no issues with the connection.
There are some limitations – the flash cart doesn’t work properly for games using extra chips on the cartridge, like the SuperFX in Star Fox, for example. Despite this, it’s an excellent, high quality build that we’re sure is a lot of fun to play out and about.
Robots, as we currently understand them, tend to run on electricity. Only in the fantastical world of Futurama do robots seek out alcohol as both a source of fuel and recreation. That is, until [Les Wright] and his beer seeking robot came along. (YouTube, video after the break.)
A Raspberry Pi 3 provides the brains, with an Intel Neural Compute stick plugged in as an accelerator for neural network tasks. This hardware, combined with the OpenCV image detection software, enable the tracked robot to identify objects and track their position accordingly.
That a beer bottle was chosen is merely an amusing aside – the software can readily identify many different object categories. [Les] has also implemented a search feature, in which the robot will scan the room until a target bottle is identified. The required software and scripts are available on GitHub for your perusal.
Mechanical watches are great in that they never need batteries, but they are simultaneously less than great in that they will lose time if not worn or otherwise regularly agitated. The ridiculous solution to this is the watch winder, which automatically rotates your mechanical watches for you, while you’re not wearing them. This is probably the item you’ll miss the least once the apocalypse hits. [Kristopher] wanted a nice quiet watch winder for his bedside table, but existing solutions were either too loud or too expensive. As is often the case, hacking ensued.
[Kristopher] had decided that starting from scratch was too much hassle. The cheaper watch winders on the market had acceptable quality enclosures, but were simply too loud. [Kristopher] sourced a $40 unit from Amazon, and proceeded to gut the drivetrain. This was replaced with a Sparkfun stepper motor and a Trinamic SilentStepStick – an advanced stepper motor driver that uses several techniques to reduce noise during operation.
An Arduino Nano was substituted as the brains of the operation, communicating with the stepper driver and allowing the winder to be configured for different wind rates. [Kristopher] reports that the device operates near-silently, and the total cost came in well below that of a high-end luxury winder.
If you are writing a hello world program, you probably aren’t too concerned about how the compiler translates your source code to machine code. However, if your code runs on something that people’s lives depend on, you will want to be a bit pickier and use something like the COMPCERT compiler. It’s a formally verified compiler, meaning there is a mathematical proof that what you write in C will be correctly translated to machine code. The compiler can generate for PowerPC, ARM, RISC-V, and x86, accepting a subset of ISO C 99 with a few extensions. While it doesn’t produce code that runs as fast as gcc, you can be sure the generated code will do what you asked it to do.
Of course, this still provides no assurance that your code will work. It just means that if you write something such as “x=0;” the generated code will set x to zero and will not do anything else. You can apply formal methods to verify your source code and be assured that the compiler doesn’t introduce possible failures. Cases where code like “x=0;” does extra things or incorrect things are very hard to figure out because the source code is correct and an examination of the generated code would be necessary to find the compiler’s code generation bug.
t’s cold outside! So grab a copy of the Hackaday Podcast, and catch up on what you missed this week.
