Computer Desk… Literally

June 30, 2012 by Mike Szczys 28 Comments

This piece of furniture begs the question, why think of a desk and a computer case as separate things? It combines Ikea furniture with electronic hardware to create the ultimate command center.

First the obvious parts: there’s a nook for the computer case that hangs just below the desktop off to the side, and the twin displays are mounted front and center. The divider between the cabinet pieces was cut away to allow the monitors to be wall-mounted. But things start to get interesting to the left of those monitors. You can see a series of dial displays in the door for that cabinet. Those meters were sourced from the MIT Flea Market and after a bit of alteration they display CPU load information fed to them by an Arduino board. This also drives some LED strips which are mounted behind the frosted glass panel that we guess could be called a back splash. The heavier the load, the better the light show.

All of the power management is taken care of in the cabinet to the right of the monitors. The top row hides a printer, external hard drive backup system, and several gaming consoles. Heat will be an issue so exhaust fans were added to each of these partitions. They’re switched based on a temperature sensor in each. It’s a lot of work, but the outcome proves it was worth it.

[via Reddit]

Bench Power Supply Resetting Thingy

June 25, 2012 by Jake W 14 Comments

As is common among some hackers, [Henry] re-purposed an ATX power supply unit to function as a bench power supply for testing circuits on a breadboard (much like this fancy example).

However, safety mechanisms on some modern PC PSUs do not automatically reset after over-current protection has kicked in, which soon became annoying for [Henry]. In order to make his power supply more hacker-friendly, he wired up and programmed an ATtiny85V, using some Arduino libraries, to do that for him. This simple project is a great example of using a hack to improve a pre-existing hack.

Raspberry Pi Finds Itself Inside A TRS-80 Model 100

June 14, 2012 by Mike Szczys 18 Comments

This TRS-80 Model 100 is a lot more powerful than you might think. That’s because [Karl Lunt] is using it as an enclosure for his Raspberry Pi board. Since the ARM-powered device comes sans-enclosure it’s fun to see a retro choice like this one. And having had to go out and buy a USB keyboard to use our own RPi, we appreciate [Karl’s] solution for using the original keyboard as an input device.

Above you can see that he’s using an LCD tv as the display. For now that connection is made using the composite video output, which explains the fuzzy image. To the right of the TRS-80 a standard wall wart connects to the barrel jack to provide power. [Karl] scrapped a USB cellphone charger in order to connect from the barrel jack to the micro-USB jack on the Pi board. The ribbon cable to the left lets him get at the I/O header without opening the case.

In order to use the keyboard he patched into it with a Teensy board. That connects to the USB port on the RPi, sending HID keyboard commands based on what it received from the user. We like this option as it give you the ability to pre-process keystrokes (ie: you can code your own custom macros that the Teensy will listen for). Right now the Model 100’s LCD screen isn’t hooked up but he may add that in the future.

Pinball Stomp: Part 2

May 7, 2012 by Caleb Kraft 3 Comments

This is the 2nd and final part of this project. If you haven’t seen part 1 yet, jump back and check it out.

Now that we have the controller box made and ready to go, we just have to build some simple stomp sensors. As I said before, I doubt this will hold anyones attention longer than a night or two. With that in mind, I wanted to make this as cheaply and simply as possible.

To make these, you need the following:

Foam board or thick cardboard
aluminum tape
wire
duct tape

That’s it… no really, that’s it. Check out the video after the break to see how it all went, and what the kids thought of it.

Continue reading “Pinball Stomp: Part 2” →

LED Case Lights Reflect CPU Usage

May 1, 2012 by Mike Szczys 7 Comments

A lot of Linux users include system monitor information in their status panel so that they can see when the CPU is grinding away. [Kevin] is taking the concept one step further by changing his case lights based on CPU usage. Above you can see green, orange, and magenta, but [Kevin’s] implementation uses the full spectrum of color.

The project is based on an ATmega48. It’s running the V-USB stack and connects to one of the motherboard’s internal USB ports. This lets him easily push the CPU usage data over to the microcontroller where it is translated into color. One RGB LED has been installed behind each fan panel on the front of the case, with a white LED above and below as an accent. Pulse-width modulation via some MOSFETs lets him mix and match for just the right color. He’s powering the add-on off of the PSU rails rather than USB so that it turns off when the computer goes to standby.

Don’t miss [Kevin’s] explanation of the system, and a demo of it in action after the break.

Continue reading “LED Case Lights Reflect CPU Usage” →

8-bit Logic Chip Computer Build

April 23, 2012 by Mike Szczys 6 Comments

[Kyle] has been hard at working building an 8-bit computer from the ground up. He’s using a set of logic IC’s for the various components, and some NVRAM chips to store the control words. What you see above is the roadmap for his instruction set. He’s just started writing them to the chips, making the job easier by building an Arduino-based programmer.

We’ve enjoyed watching [Quinn Dunki’s] progress with her ~~Z80~~ 6502-based PC build which started on a breadboard in much the same way but has come a long way since those humble beginnings. Recently we also looked in on a 4-bit computer that is using discrete components. But [Kyle’s] take on the challenge falls somewhere in between the two.

The gist of his design can be found in one of his earlier post. He’s got a ring counter which starts by clearing the address register. It then loads the NVRAM address of the next instruction which is then executed on the subsequent count. It seems the build still has some way to go so make sure to keep your eye out for updates.

[via Reddit]

Building A Computer With Discrete Transistors

April 20, 2012 by Mike Szczys 21 Comments

You’re going to want to do some stretching before undertaking a soldering project like this one. We’re betting that the physical toll of assembling this 4-bit discrete processor project is starting to drive [SV3ORA] just a bit crazy. This small piece of electronic real estate is playing host to 62 transistors so far, and he’s not done yet.

It’s one thing to build some logic gates in Minecraft (and then turn then into a huge 16-bit ALU). But it’s another thing to actually commit to a physical build. [SV3ORA] does a great job of showing the scope of the project by posting a tight shot of one inverter, then three in a row, then the entire 8-bit address and display system. These gates are built on the copper side of the board, with the power feed, LEDs for displays, and jumpers for control on the opposite side. We’re excited to see where he goes with this project!

But hey, if you don’t want to do that much soldering there’s a lot you can do on a few breadboards.