Converting Parallel Port CNCs To USB

If you’re looking for a small, benchtop CNC machine for PCBs and light milling the ubiquitous Sherline CNC machine is a good choice. There’s a problem with it, though: normally, the Sherline CNC controller runs off the parallel port. While some of us still have a Windows 98 battlestation sitting around, [David] doesn’t. Instead, he built a USB dongle and wrote the software to turn this mini CNC into something usable with a modern computer.

First up, the hardware. The core of this build is the rt-stepper dongle based around the PIC18F2455 microcontroller. With a bare minimum of parts, this chip converts USB into a parallel port for real-time control. It’s fast — at least as fast as the parallel port in the ancient laptops we have sitting around and plugs right into the CNC controller box for the Sherline.

The software is where this really shines. the application used to control this dongle is a hack of the EMC/LinuxCNC project written in nice, portable Python. This application generates the step pulses, but the timing is maintained by the dongle; no real-time kernel needed.

There are a lot of choices out there for a desktop CNC machine made for routing copper clad board, wood, brass, and aluminum. The Othermill is great, and Inventables X-Carve and Carvey are more than up for the task. Still, for something small and relatively cheap, the Sherline is well-regarded, and with this little dongle you can actually use it with a modern computer. Check out the demo video below.

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DARPA Plans To Begin Hacking Human Brains

So [DARPA] wants to start hacking human brains, With the help of the biomedical device center at the university of Texas in Dallas. This does sound a bit crazy but DARPA does crazy. Conspiracy theorists are going to have a field day with this one.

The initial plans to turn us all into mindless zombies seem to be shelved for now, however they are working on what they call Targeted Neuroplasticity Training (TNT), which they explain means using the body’s nervous system to enhance and speed up the learning process. This could be achieved by using a process known as ‘synaptic plasticity‘ which opens and closes the brains synapses with electrical stimulation. They hope that by tuning the neural networks responsible for cognitive function it will enhance learning. Let’s just hope they don’t turn any humans into DARPA falling robots.

A Smart Table For Gamers

When makers take to designing furniture for their own home, the results are spectacular. For their senior design project, [Phillip Murphy] and his teammates set about building a smart table from the ground up. Oh, and you can also use it to play games, demonstrated in the video below.

The table uses 512 WS2812 pixels in a 32 x 16 array which has enough resolution to play a selection of integrated games — Go, 2-player Tetris, and Tron light cycle combat — as well as some other features like a dancing bird party mode — because what’s the point of having a smart table if it can’t also double as rave lighting?

A C2000-family microcontroller on a custom board is the brains, and is controlled by an Android app via Bluetooth RN-42 modules. The table frame was designed in Sketchup, laser-cut, and painstakingly stained. [Murphy] and company used aluminum ducting tape in each of the ‘pixels’, and the table’s frame actually forms the pixel grid. Check out the overview and some of the games in action after the break.

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4-LED Octal Clock Demands Colorful Math

We’ve all seen LED clocks where RGB LEDs are used to display time. It seems like the simpler the interface, the more likely you’d need to do math to figure out the time. This Octal Clock by [Alex Kurrasch] proves the point by using only four LEDs: the top two show hours and minutes, and the bottom two LEDs are multipliers.

Using octal numbering, [Alex] translates the data using a Venn diagram of color mixing. The mapping uses 1 as red, 2 as green, followed by yellow, blue, magenta, and cyan. It ends with 7 as white (all on) and 0 as black (all off).

As the time changes, a fading algorithm changes the display to match. He offers the time of 7:38pm as an example in the grid shown here. Base-8 math is provided; don’t worry, you’ll get really good at this if you make your own wristwatch version… people will learn to never ask you about the time.

The clock uses a ATMega64 running assembly language firmware with a DS1306E+ RTC chip keeping track of time. The enclosure is cool too; [Alex] milled the case out of mahogany and the front and back plates are anodized aluminum. The unique looking diffusers on the LEDs are actually paraffin, a trick that [Elliot Williams] mentioned in his recent article on diffuser materials.

Hackaday Prize Entry: Electro-Magnetic Enabled Bagpipes

Bagpipes are an instrument at least a millennia old, the most popular of which, in modern times, is the Great Highland bagpipe. There are other types of bagpipes, some of which have a bellows rather than requiring the player to manually inflate the bag by breathing into it. The advantage of the bellows is that it delivers dry air to the bag and reed (instead of the moist air from the player’s breath) and this dryness means that the instrument stays in tune better and the reed lasts longer.

[TegwynTwmffat] has built his own Irish uilleann pipes, (one of the types that use a bellows) using a carbon steel chanter (the part with the finger holes) and a steel reed. The reed vibrates and a pickup is used to convert this vibration into an electric signal, similar to the way a guitar pickup converts a vibrating string into an electric signal. This means that the signal from [Tegwyn]’s pipes can be sent to an amplifier. It also means that the signal can be processed the same way as the signal from an electric guitar – through distortion, flanger, wah, or delay pedals, for example.

[Tegwyn] has put up a drawing of the chanter showing dimensions and locations of the holes and has posted a couple of songs so you can hear the pipe in action. The first has the pipes without any effects on them, the second with effects. The comments for the second say that there are no electric guitars in the song – it’s all the pipes! Bagpipes seem to be a (relatively) popular instrument to hack and we’ve seen a couple of them over the years, such as this one made from duct tape, and this one – an electronic version.

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Learn by Fixing: Another Verilog CPU

Because I often work with students, I’m always on the look-out for a simple CPU, preferably in Verilog, in the Goldilocks zone. That is, not too easy and not too hard. I had high hopes for this 16-bit RISC processor presented by [fpga4student], but without some extra work, it probably isn’t usable for its intended purpose.

The CPU itself is pretty simple and fits on a fairly long web page. However, the details about it are a bit sparse. This isn’t always a bad thing. You can offer students too much help. Then again, you can also offer too little. However, what was worse is one of the modules needed to get it to work was missing! You might argue it was an exercise left to the reader, but it probably should have been pointed out that way.

At first, I was ready to delete the bookmark and move on. Then I decided that the process of fixing this design and doing a little analysis on it might actually be more instructive than just studying a fully working design. So I decided to share my fix with you and look inside the architecture a bit more. On top of that, I’ll show you how to get the thing to run in an online simulator so you can experiment with no software installation. Of course, if you are comfortable with a Verilog toolchain (like the ones from Xilinx or Altera, or even free ones like Icarus or CVer) you should have no problem making that work, either. This time I’ll focus on how the CPU works and next time I’ll show you how to simulate it with some free tools. Continue reading “Learn by Fixing: Another Verilog CPU”

Neural Networks Walk Better Than Humans for Game Animation

Modern day video games have come a long way from Mario the plumber hopping across the screen. Incredibly intricate environments of games today are part of the lure for new gamers and this experience is brought to life by the characters interacting with the scene. However the illusion of the virtual world is disrupted by unnatural movements of the figures in performing actions such as turning around suddenly or climbing a hill.

To remedy the abrupt movements, [Daniel Holden et. al] recently published a paper (PDF) and a video showing a method to greatly improve the real-time character control mechanism. The proposed system uses a neural network that has been trained using a large data set of walking, jumping and other sequences on various terrains. The key is breaking down the process of bipedal movement and its cyclic behaviour into a series of sub-steps or phases. Each phase translates to a natural posture for the character while moving. The system precomputes the next-phases offline to conserve computational resources at runtime. Then considering user control, previous pose of the character(including joint positions) and terrain geometry, the consequent frame of the animation is computed. The computation is done by a regression network that calculates future position of the joints and a blending function is used for Motion Matching as described in a presentation (PDF) and video by [Simon Clavet]. Continue reading “Neural Networks Walk Better Than Humans for Game Animation”