Bootable Emulator For The DCPU

July 9, 2012 by 16 Comments

[Notch], the guy behind Minecraft, is currently working on a new game called 0x10c. This game includes an in-game 16-bit computer called the DCPU that hearkens back to the 1980s microcomputers with really weird hardware architecture. [Benedek] thought it would be a great idea to turn his ThinkPad into a DCPU, so he wrote a bootable x86 emulator for the DCPU that is fully compliant with the current DCPU spec.

This bootable DCPU emulator comes from the fruitful workshop of [Benedek], the brains behind drawing fractals on the DCPU, emulating bit-flipping radiation, and even putting the Portal end credits inside [notch]’s 0x10c computer.

[Benedek] wrote this new in x86 assembly, allowing it to be booted without an OS from a USB flash drive on any old laptop. This allows for direct hardware communication for everything implemented for the DCPU so far.

If you’d like to run your bare-metal DCPU, [Benedek] made all the files avaiable. Since the entire emulator is only 1800 lines of x86 assembly, it’s possible to load this off a floppy disk; an ancient tech we’ll be seeing in [notch]’s new game.

Oh. One more thing. When we were introduced to 0x10c, we said we’ll be holding a contest for the best hardware implementation of the DCPU. We’re still waiting on some of the hardware specs to be released (hard drives and the MIDI-based serial interface), so we’ll probably be holding that when there is a playable alpha release. [Benedek]’s bootable emulator is a great start, though.

Ask Hackaday: How About Some Model Rocket Hacks?

July 9, 2012 by 35 Comments

There’s nothing like the smell of black powder in the morning, along with the excitement and burnt propellant in the air that comes after launching a model rocket. All those 60s, 70s, 80s and 90s kids out there may remember the classes of model rocket engines – generally A, B, C, and D sized engines used to push your cardboard tube with balsa fins skyward.

A lot has changed in the world of model and amateur rocketry in the last few years. In 2009, the Tripoli Rocketry Association won a lawsuit against the Bureau of Alcohol, Tobacco, Firearms and Explosives to allow the sale of Ammonium perchlorate rocket engines to anyone. This lawsuit took almost 10 years to come to a head, but finally anyone can walk into Hobby Lobby and come out with D, E, F, and G engines in hand. Even our old favorite, Estes rockets, has gotten into the game by putting out a few awesome G-powered kits. With these off-the-shelf motors, anyone (in the US, at least) can launch a G-powered model rocket weighing under 1500 grams (3.3 lbs) without the need for a certification.

With that in mind, we’re putting out a call for model rocket hacks. If you put together an microcontroller-powered altimeter project, awesome. Send it in. On board video camera? Great! Even if you built a huge replica of the Titan IIIe (or the Estes Star Rider, a personal favorite), send that thing in. If you’re going for a huge Saturn V, the record to beat is a 1/10 scale model, so get on it.

Adding More Frequencies To Your Software Defined Radio

July 8, 2012 by 32 Comments

[regveg] was looking for a way to receive signals outside the normal 64-1700MHz range his TV tuner software defined radio dongle can get. After finding a few $100+ upconverters on the Internet, he stumbled across a DIY project that greatly expands the frequencies his RTLSDR can receive.

[George]’s upconverter uses heterodyning to increase the frequencies received by a SDR dongle. The basic idea is mixing a signal from an antenna with a 100MHz frequency oscillator. The resulting output will be λ + 100MHz and λ – 100MHz, allowing for a wider range of frequencies that can be received by the SDR TV tuner dongle.

Now [regveg] has a board and schematic that makes it possible to receive just about anything with his TV tuner dongle. Interestingly, this upconverter contains less than $10 in parts and is easily etched at home thanks to a single-sided construction and through-hole parts.

As a small aside, [Andrew] sent in a tip a few days ago telling us his RTL dongle didn’t have any ESD protection. This is a very bad thing, but the good news is the fix is very cheap: just solder in a 10 cent diode and you’re good to go.

Proximity Switch For Your Mains Devices

July 8, 2012 by 17 Comments

[Ivan’s] friend built a proximity sensor to switch his LED bench lighting off every time he walked away. The idea is pretty neat, so [Ivan] decided to implement it for mains devices by making this proximity switched outlet box.

A Sharp GP2D12 infrared distance sensor is the key to the system. It has an emitter and receiver that combine to give distance feedback base on how much of the light is reflected back to the detector. This is presented as a voltage curve which is monitored by an ATtiny85 (running the Arduino bootloader). It is small enough to fit inside the outlet box along with a tiny transformer and linear regulator to power to logic circuitry. The mains are switched with a relay using an NPN transistor to protect the chip’s I/O pins.

Check out the video after the break to see this in action. It should be a snap to add a count-down timer that gives you a bit more freedom to move around the workshop. With that in place this is a fantastic alternative to some other auto-shutoff techniques for your bench outlets.

Continue reading “Proximity Switch For Your Mains Devices” →

Tug Of War… With Your Mind, Man!

July 8, 2012 by 17 Comments

Challenge your friends to a little mental Tug of War thanks to the Omaha Maker Group’s Red Bull Creation contest entry. The power struggle is all in your mind, and can only be won if you’re able to concentrate deeply and quickly. The headsets worn by each competitor monitor brain waves over a ten second window. If you concentrate more deeply than your opponent they’ll get a squirt of water in the face. If no one is concentrating well the contest is a draw the measurements start again. The screenshot above was taken from the test footage found after the break.

Hardware details are scant on this one. Obviously the Bullduino is the centerpiece of the build, taking readings from the headsets. A motor moves the water nozzle along a slit cut in the top of the sphere.  Progress during the 10-second window is displayed by that nozzle, which starts in the center yellow ‘safe’ zone and moves to one side or another to enter the green ‘kill’ zone.

Continue reading “Tug Of War… With Your Mind, Man!” →

Adding An Auto-shutoff To The Simplest Of Drip Coffee Makers

July 8, 2012 by 15 Comments

[Jerry Pommer] and his wife have relied on a percolating coffee pot for years. We have fond memories of camping trips with these things; they make great coffee which tastes even better on a cold morning in the back woods. But a recent package from the stork means that they no longer have time to sit and watch the coffee perk. After several days of boil-overs [Jerry] switched to this very basic drip coffee maker he salvaged from the trash pile. It has one switch that turns it on and off and nothing else. In order to make sure he doesn’t forget to turn it off, he hacked together his own shut-off timer for the device.

His write-up is all back story, but the 34 minute video embedded after the break takes us through the hack itself. We like it that he starts by discussing the different options that he could have chosen. Of course it might have been a microcontroller, or a 555 timer keeping time. But in the end he went with a simple resistor-capacitor timer. The carefully calculated component pair drives a Darlington transistor which keeps a relay closed. When the slowly draining capacitor lets the voltage drop past a certain threshold it also kills the power to the hot plate. In this case it will only stay on for about a half hour.

Continue reading “Adding An Auto-shutoff To The Simplest Of Drip Coffee Makers” →

Another Switch Mode Regulator Swap For The Raspberry Pi

July 7, 2012 by 32 Comments

[Karl Lunt] is working to slim the Raspberry Pi current draw as much as possible. The first step in his journey was to replace the linear voltage regulator with this switch mode version. It’s a step-down voltage regulator circuit with a tiny footprint and a matching price tag (about $10) made by Pololu. It’s small enough to be mounted in the empty space between the LCD ribbon connector and the main processor.

The project was based on the hack we saw at the end of June. But we give much more credit to [Karl] for removing the old part in a safer way. He clipped the two small leads on the bottom of the old part, then used a beefy iron to sufficiently heat the large pad before removing the body of it. With the old part out of the way it’s just a matter of connecting the three wires in the right configuration.

This cut consumption by about 50 mA. He’s hoping to do more by removing the on-board LEDs. His goal is a draw of under 250 mA in order to make it last a reasonable amount of time when running from batteries.