Building A Computer Around A TTL CPU

[Bill’s] worked on his homebrew computer for almost a decade. He didn’t start with a Z80 processor like a lot of the projects we’ve seen, but instead build the CPU itself from 74-series TTL chips and a ridiculous amount of wire wrapping to connect it all.

The video after the break shows off the functionality. We love the front panel, which is packed with information but manages to remain organized and offers many convenient features. Our favorite is the ability to pause execution and scroll through the registers by spinning the dial. The clock signal has a variable speed which is selected by an internal DIP switch package that can be changed during a pause. It runs MINIX and has a library of programs, but perhaps most surprising is its ability to serve webpages.

Lately we’ve been interested in drilling down through program language abstractions to understand what is going on inside the silicon. This has given us new respect for those building processors from scratch. Think of it this way, if you actually need to build each instruction out of gates, you’ll be able to understand how those instructions work at the most fundamental level.

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LED Headgear Is Marvel Of Free-formed Circuitry

Hackaday contributor [Nick Schulze] popped out an impressive set of LED headgear for a hat-themed party.

[Nick] is no stranger to working with LEDs. Previously he built a blue 8x8x8 cube something like this other 512 node full color version. He had a bunch of LEDs left over from that project and decided to put them to good use.

The first part of the build is the frame itself, made from thick fencing wire. He just started bending it around his head and got an uncomfortable head-shaped hoop to which he could solder. From there, enameled copper wire wraps its way through the system, supplying logic levels to all of the LEDs. Everything is done without a circuit board of any kind. The LED drivers themselves are attached by first using a zip tie to affix a resistor to the frame, then by soldering the TLC5916 chip to that resistor. Even the ATmega8 is included dead-bug style by soldering it to the frame which we think servers as ground. Program it with the free-floating female pin header and you’ll get the fantastic animations seen in the video after the break.

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FPGA Arduino Shield Uses Kickstarter As A Preorder System

[ Jack Gassett] is working on an FPGA shield for the Arduino. At first the idea of this expansion board seemed a little silly. But [Jack] mentions that the FPGA board can be quite useful for adding higher-order electronic complexity like HDMI capabilities to an Arduino. We’re not totally sold on the idea, but he’s not making the board solely for use with an Arduino either.

The plan is to use a Xilinx Spartan 3A FPGA which comes in a ball-grid array package. And that is the reason [Jack] decided to use Kickstarter for this project. He shared some of his issues with BGA components in a home manufacturing process a while back. To get these working reliably you need to have them professionally assembled, and that requires a sizable upfront investment. But as we read through his proposal it struck us that he’s actually using Kickstarter as a preorder system. You can get a base model with just the FPGA soldered on the board for $55. Not bad considering the chip will cost you at least $20 without assembly. Each level up includes a few more components like SRAM or add-on PCBs.

We get a lot of tips pointing to Kickstarter proposals but this is one of the few that seems right on the mark for supporting open and innovative development. Great work [Jack]!

[Thanks Simon]

VGA Pong On A ChipKIT

[Nathan] got his hands on a chipKIT Uno32 development board and wrote a Pong sketch that you can play with a VGA monitor. We love the hardware that makes this feel very much like the classic. It uses a collection of resistor-based digital to analog converters to generate the color signals for the VGA protocol. The score for each player is show on a 7-segment display instead of being printed on-screen. And the paddles are made up of a pair of potentiometers.

You’ll remember that the chipKIT Uno32 is an Arudino compatible 32-bit development board. This project shows how the hardware handles, and how easy it can be to generate VGA signals with it if you know what you’re doing.

For those interested in the game physics themselves, [Nathan] provided a nice explanation about ball movement at the bottom of his post. If you need even more details, dive into the code package that he links to.

Playing DVDs On An IPad

[Harrison Jackson] figured out how to add DVD playback to an iPad. It doesn’t require a jailbreak, or any hardware modifications to your prized tablet. The work is done with some server-side processing and played back through the browser.

The popular open-source multimedia player VLC has the ability to encode from the command line during playback. [Harry’s] option flag mastery of the program allows him to convert a DVD to a 320×240 format that is iPad friendly. But this alone doesn’t get the video any closer to being on the iDevice. You’ll need to be running a webserver that can stream video. This example is on OSX, but since he’s using an Apache server it should be simple to reproduce on any Unix variant. Once you’ve enabled m3u8 files in the Apache mime-types, the iPad browser can be pointed to the file address VLC is kicking out and you’ll be watching a movie in no time.

We’ve wondered about replacing our home theater front-end with an ATV 2 running XBMC but the thought of having no optical drive in the living room requires some contemplation. If this becomes a feasible option (that isn’t downscaled from DVD quality) it will be a no-brainer to make that jump.

Don’t miss the demo video after the break. Full instruction are in the comment section of that clip.

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Skateboard Tagging

We abhor vandalism, but we love art. Here’s a skateboard hack that lets skate punks young and old tag their turf while they ride. [D*Face], a multimedia street artist who grew up in London, added a mounting system to the bottom of his skateboard which includes a can of spray paint. We’re a bit surprised that there’s room enough for that, but the system fits nicely. They’re not locked into a constant stream because the system lets the rider (or a bystander) actuate the spray can via remote control.

But the brush is only one part of the painter’s tool chain. To get the most interesting effect, a pool was painted white to serve as canvas and a troupe of skaters was unleashed on it to try out the modified boards. Check out the video after the break to see the colorful and pleasing curves that result. We just hope nobody bailed and smeared the canvas at the same time.

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Red Bull Creation Contest Results

72 hours of hacking came to a head with the completion of the Red Bull Creation. This years challenge was to build something out of junk that moves a human. It’s hard to pull all the aspects of the event together in one place, so here’s some links you’ll want to check out if you weren’t able to attend.

Tech Crunch has an overview of all the event winners. One of our favorites is pictured above. The spinning see-saw is not your average playground toy. Its built-in accelerometer waits for the forces to peak, then snaps a picture for later enjoyment. Techshop, a San Francisco hackerspace, took the team prize for their work on it. Don’t miss the video after the break

The overall winner was a team from Minneapolis called 1.21 Jigawatts. They produced a human-sized hamster wheel that pulled a small follower behind it. As you walk, the follower prints incoming text messages on the sidewalk, kind of like the chalkbot. We searched around for video of it, the best we could find is this one.

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