Author: Brian Benchoff

5252 Articles

Emulating A Hard Drive With The Raspberry Pi

August 11, 2015 by 35 Comments

[Chris] recently moved a vintage IBM 5150 – the original PC – into his living room. While this might sound odd to people who are not part of the Hackaday readership, it actually makes a lot of sense; this PC is a great distraction-free writing workstation, vintage gaming machine, and looks really, really cool. It sat unused for a while, simply because [Chris] didn’t want to swap out piles of floppies, and he doesn’t have a hard drive or controller card for this machine. After reviewing what other retrocomputer fans have done in this situation, he emulated a hard drive with a Raspberry Pi.

The traditional solution to the ‘old PC without a hard drive’ problem is the XTIDE project. XTIDE is a controller card that translates relatively new IDE cards (or an emulated drive on another computer) as a hard drive on the vintage PC, just like a controller card would. Since a drive can be emulated by another computer, [Chris] grabbed the closest single board computer he had on hand, in this case a Raspberry Pi.

After burning an EPROM with XTIDE to drive an old network card, [Chris] set to work making the XTIDE software function on the Raspberry Pi side of things. The hardware on the modern side of the is just a Pi and a USB to RS232 adapter, set to a very low bitrate. Although the emulated drive is slow, it is relatively huge for computer of this era: 500 Megabytes of free space. It makes your head spin to think of how many vintage games and apps you can fit on that thing!

Vulcan 74: A Masterpiece Of Retro Engineering

August 11, 2015 by 48 Comments

[Radical Brad] has played around with FPGAs, video signals, and already has a few astonishing projects of bitbanged VGA on his resume. Now he’s gone insane. He’s documenting a build over on the 6502.org forums of a computer with Amiga-quality graphics built out of nothing but a 65C02, a few SRAM chips, and a whole pile of logic chips.

The design goals for this project are to build a video game system with circa 1980 parts and graphics a decade ahead of its time. The video output is VGA, with 400×300 resolution, in glorious eight-bit color. The only chips in this project more complex than a shift register are a single 65c02 and a few (modern) 15ns SRAMs. it’s not a build that would have been possible in the early 80s, but the only thing preventing that would be the slow RAM chips of the era.

So far, [Radical] has built a GPU entirely out of 74-series logic that reads a portion of RAM and translates that to XY positions, colors, pixels, and VGA signals. There’s support for alpha channels and multiple sprites. The plan is to add sound hardware with support for four independent digital channels and 1 Megabyte of sample memory. It’s an amazingly ambitious project, and becomes even more impressive when you realize he’s doing all of this on solderless breadboards.

[Brad] will keep updating the thread on 6502.org until he’s done or dies trying. So far, it’s looking promising. He already has a bunch of Boing balls bouncing around a display. You can check out a video of that below.

Continue reading “Vulcan 74: A Masterpiece Of Retro Engineering” →

Hackaday Prize Entry: A Tiny Tool For Car Hacking

August 10, 2015 by 23 Comments

A car from 1940 would have been an almost completely mechanical device. These days though, a car without electricity wouldn’t run. It’s not the engine – it’s the computers; the design details of which automotive manufacturers would love to keep out of the hands of hardware hackers like us. [Mastro Gippo] wanted to build a small and powerful CAN bus reverse engineering tool, and the Crunchtrack hits it out of the park. It’s a CAN bus transceiver, GPS receiver, and GSM modem all wrapped up into a single tiny device that fits under your dash.

[Mastro] has a slight fetish for efficiency and tiny, tiny devices, so he’s packaging everything inside the shell of a standard ELM327 Bluetooth adapter. This is a device that can fit in the palm of your hand, but still taps a CAN bus (with the help of a computer), receives GPS, and sends that data out over cell phone towers.

The device is based on the STM32 F3 ARM microcontroller (with mbed support), a ublox 7 GPS module, and an SIM800 GSM module, but the story doesn’t stop with hardware. [Mastro] is also working on a website where reverse engineering data can be shared between car hackers. That makes this an excellent Hackaday Prize entry, and we can’t wait to see where it goes from here.

The 2015 Hackaday Prize is sponsored by:

Hackaday Prize Entry: Vertical Aeroponics

August 9, 2015 by 32 Comments

For his Hackaday Prize entry, [MIPS ARMSTRONG] is working on an open-source terrarium that will be one of the fastest way to grow foodstuffs or other edible greens. He’s calling it Project EDEN, and it’s shaping up to be one of the most advanced homebrew horticultural devices ever made.

There are a few things that make this indoor greenhouse unique. The most obvious is the incredible number of LEDs used as grow lights. [MIPS] is using 900 Watts worth of Royal Blue and Deep Red LEDs. To water these plants, [MIPS] is taking a cue from NASA and building a High Pressure Aeroponics system – a device that shoots droplets of water only 50 microns in diameter directly onto the roots of the plants.

One of the more interesting aspects of EDEN is the CO2 system. The bulk of plant biomass – like humans – comes from carbon, and plants get their carbon from the atmosphere. Studies have shown that increasing the concentration of CO2 in a grow chamber can increase plant growth. There is a limit before CO2 becomes toxic to plants, so [MIPS] will have to keep a close eye on the CO2 levels with gas sensors.

With high-pressure watering, a CO2 system, and an amazing array of LEDs, this is one of the most advanced homebrew horticulture projects on the planet. It’s also a great fit for this year’s Hackaday prize theme of ‘build something that matters’, and we can’t wait to see [MIPS]’s future developments of his awesome aeroponic terrarium.

The 2015 Hackaday Prize is sponsored by:

DEF CON: HDMI CEC Fuzzing

August 9, 2015 by 10 Comments

HDMI is implemented on just about every piece of sufficiently advanced consumer electronics. You can find it in low-end cellphones, and a single board Linux computer without HDMI is considered crippled. There’s some interesting stuff lurking around in the HDMI spec, and at DEF CON, [Joshua Smith] laid the Consumer Electronics Control (CEC) part of HDMI out on the line, and exposed a few vulnerabilities in this protocol that’s in everything with an HDMI port.

CEC is designed to control multiple devices over an HDMI connection; it allows your TV to be controlled from your set top box, your DVD player from your TV, and passing text from one device to another for an On Screen Display. It’s a 1-wire bidirectional bus with 500bits/second of bandwidth. There are a few open source implementations like libCEC, Android HDMI-CEC, and even an Arduino implementation. The circuit to interface a microcontroller with the single CEC pin is very simple – just a handful of jellybean parts.

[Joshua]’s work is based off a talk by [Andy Davis] from Blackhat 2012 (PDF), but greatly expands on this work. After looking at a ton of devices, [Joshua] was able to find some very cool vulnerabilities in a specific Panasonic TV and a Samsung Blu-ray player.

A certain CEC command directed towards the Panasonic TV sent a command to upload new firmware from an SD card. This is somewhat odd, as you would think firmware would be automagically downloaded from an SD card, just like thousands of other consumer electronics devices. For the Samsung Blu-Ray player, a few memcpy() calls were found to be accessed by CEC commands, but they’re not easily exploitable yet.

As far as vulnerabilities go, [Joshua] has a few ideas. Game consoles and BluRay players are ubiquitous, and the holy grail – setting up a network connection over HDMI Ethernet Channel (HEC) – are the keys to the castle in a device no one  would ever think of taking a close look at.

Future work includes a refactor of the current code, and digging into more devices. There are millions of CEC-capable devices out on the market right now, and the CEC commands themselves are not standardized. The only way for HDMI CEC to be a reliable tool is to figure out commands for these devices. It’s a lot of work, but makes for a great call to action to get more people investigating this very interesting and versatile protocol.

DEF CON: Abusing Scripts In Multiplayer Games

August 8, 2015 by 11 Comments

Everyone has at least a few games on their computer, and I would assume most of the Hackaday readership would be among the enlightened PC gamer bretheren. At this year’s DEF CON, [Tamas Szakaly] gave a talk about the data these games leak to the Internet, the data they accept from the Internet, and what you can do with that data.

[Tamas]’ talk was entirely about scripting games, like the many games that are scriptable in Lua, or Valve’s Squirrel. Developers have thought about this before and have implemented sandboxes and many anti-cheat mechanisms. However, because these sandboxes are poorly implemented, it’s easy to get outside the game and do some real damage.

[Tamas]’ first target was Crysis 2 and the CryEngine3. This game uses a Lua scripting engine and has no sandbox whatsoever. That means [Tamas] can call os.execute, and from there the entire game is over. Or it’s just begun. Either way you look at it, it’s pretty bad.

CryTek notwithstanding, [Tamas] can also use games with Lua scripting that have a real sandbox. DOTA2 has a leaky sandbox and can be used to call OS I/O routines and execute base 64 encoded executables right over the main executable.

The most impressive example of script abuse in various multiplayer games is from Garry’s Mod. This game has custom implementation of dangerous functions, restricted file IO, and a proper Lua sandbox. This was a wise decision from the developers, but the library is huge. If you create a map or mode used on a server, you can have a full HTTP proxy to the gamer’s home network. During the talk, [Tamas] used this exploit to display an image from a webcam on a Garry’s Mod server. It was on the podium right next him, but this could have been done on a server on the other side of the planet.

Continue reading “DEF CON: Abusing Scripts In Multiplayer Games” →

Hackaday Prize Entry: DIY Guitar Multieffects

August 8, 2015 by 14 Comments

Guitar effects and other musical circuits are a great introduction to electronics. There’s a reason for this: with audio circuits you’re dealing with analog signals and not just the ones and zeros of blinking a LED. Add in the DSP aspects of audio effects, and you have several classes of an EE degree wrapped up in one project.

For his Hackaday Prize entry, [randy.day] is building a guitar multieffect. Instead of just a single distortion, fuzz, or chorus circuit, this tiny little PCB is going to have several flavors of pitch shifting, a flanger, chorus, echo, harmony, and stranger ‘digital-ish’ effects like bitcrushing.

This effects unit is built around a PIC32 and a TI audio codec which processes the audio at 64k 32-bit samples/second. This takes care of all the audio processing, but the hard work for a guitar pedal is actually the enclosure and mechanicals – it’s a hard life for stage equipment. For the foot pedal input, [randy] is using a magnetic position sensor, but there’s no word if he’ll be using a fancy die-cast enclosure or a plastic injection molded unit.

The 2015 Hackaday Prize is sponsored by: