Making Vector Arcade Games With An FPGA

August 10, 2013 by Brian Benchoff 11 Comments

While we’re sure most Hackaday readers were raised by arcade games featuring sprites, pixels, and other shiny brightly colored squares, this was not always so. Many classic arcade games – Lunar Lander, Gravitar, and Asteroids in particular – used vector displays. Instead of drawing individual pixels, these games functioned more like an oscilloscope, drawing lines. When [Todd] and [Andrew] got their hands on a monitor from an old Asteroids cabinet, they knew what they had to do: build their own vector arcade game.

The guys made their own DAC and Amplifier board that plugs right in to a Nexys2 FPGA dev board. This was after they tested out some 3D drawing code with a gnarly handmade R2R DAC they used to draw and rotate a cube on an oscilloscope screen.

Not only did the guys build a vector video card, they also connected the FPGA’s VGA out to a monochrome monitor for an in-game HUD. Awesome work that blows away anything available in the golden days of vector arcade games. It’s a beautiful piece of engineering that certainly deserves its own cabinet.

Video of the game available below.

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Avalanche Pulse Generator Design

August 6, 2013 by Mike Szczys 25 Comments

avalanche-pulse-generator

This avalanche pulse generator is a great way to test your mettle as an Electronics Engineer. The challenge is to truly understand how each part of the design works. We certainly got a failing grade when first studying the schematics more than a week ago. But we’re slowly beginning to understand what’s going on under the hood.

The concept of an avalanche transistor is some wicked voodoo from the analog side of the street which leverages a transistor’s breakdown voltage to achieve a predictable result. In laymen’s terms it (mis)uses a transistor to produce a really fast pulse. The write-up linked above references several previous avalanche pulse generator designs, but this one is a bit different in how it produces about 50V from a pair of AAA batteries using a multivibrator circuit.

Even if you have no idea what’s going on here you may be interested in the last few paragraphs where the circuit is measured using a cutting-edge Teledyne LeCroy Wavemaster 820Zi-A. That’s a 20 GHz scope with a 15.3″ screen which you’ll never ever own.

[Sprite_TM] OHM2013 Talk: Hacking Hard Drive Controller Chips

August 2, 2013 by Mike Szczys 16 Comments

Even if he hadn’t done any firmware hacking on this hard drive [Sprite_TM’s] digital exploration of the controller is fascinating. He gave a talk at this year’s Observe, Hack, Make (OHM2013) — a non-commercial community run event in the Netherlands and we can’t wait for the video. But all the information on how he hacked into the three-core controller chip is included in his write up.

[Sprite_TM] mentions that you’re not going to find datasheets for the controllers on these drives. He got his foot in the door after finding a JTAG pinout mentioned on a forum post. The image above shows his JTAG hardware which he’s controlling with OpenOCD. This led him to discover that there are three cores inside the controller, each used for a different purpose. The difference between [Sprite_TM’s] work and that of mere mortals is that he has a knack for drawing surprisingly accurate conclusions from meager clues. To see what we mean check out the memory map for the second core which he posted on page 3 of his article.

Using JTAG he was able to inject a jump into the code (along with a filler word to keep the checksum valid) and run his own code. To begin the firmware hacking portion of the project he pulled the flash ROM off of the board and installed it on that little board sticking out on the left. This made it easy for him to backup and reflash the chip. Eventually this let him pull off the same proof of concept as a firmware-only hack (no JTAG necessary). He goes onto detail how an attacker who has root access could flash hacked firmware which compromises data without any indication to they system admin or user. But we also like his suggestion that you should try this out on your broken hard drives to see if you can reuse the controllers for embedded projects. That idea is a ton a fun!

When we were poking around the OHM2013 website (linked above) we noticed that the tickets are sold out; good for them! But if you were still able to buy them they take Bitcoin as one payment option. Are there any other conferences that allow Bitcoin for registration?

BeagleBone Black Becomes A Handheld Classic Gaming Console

July 30, 2013 by Brian Benchoff 13 Comments

Over at TI, the 2013 Intern Design Challenge is underway, an opportunity for the interns of TI to flex their engineering muscle for a few prizes and a chance to have their designs turned into actual products. We’re thinking [Max] might just pull this one out with his BeagleBone Gaming Cape, an add-on to the BeagleBone Black that turns this ARM-powered Linux board into a retro gaming system.

The build was inspired by [Max]’s earlier MSP430 Launchpad GamingPack, an add-on board for the Launchpad that put two NES controllers, a VGA out, and an FPGA to create a custom gaming console that’s up there with the brightest and best consoles of the 16-bit era. For the new BeagleBone-based build, [Max] eschewed off-board processing, but did manage to include a magnetometer/accelerometer and an audio codec IC to provide the best gaming experience for all those NES, Game Gear. Gameboy, GBA and Doom .wad games.

In addition to a fabulous piece of hardware, [Max] also has the case design down to a tee. He first printed out a dozen or so layers of his case, sandwiching the BeagleBone, his cape, battery holders, and LCD display. Once he knew the dimensions would work, he sent his files off to be laser cut out of a matte black delrin. The finished piece is a work of art, and considering how well everything goes together, we wouldn’t mind giving this new retro-gaming console a spin ourselves.

Rekindling Forth With A Propeller Jupiter Ace

July 28, 2013 by Brian Benchoff 26 Comments

Jupiter

The Jupiter Ace was a small membrane keyboard, cassette tape drive computer akin to the ZX Spectrum released in 1982. Priced at £90, it was a little more expensive than its home computer contemporaries, but had a very interesting feature: instead of BASIC, the Ace ran Forth. This interpreted stack-based language is far more capable than the BASIC variants found on home computers of the day, but unfortunately the Ace failed simply because Forth was so foreign to most consumers.

Not wanting to let a good idea die, [prof_braino] is bringing Forth back into the modern age. He’s using a Parallax Propeller to emulate a simple home computer running Forth. Instead of a book-sized computer, the new Propeller version runs on a single chip, with 8 CPU cores running 24 times faster than the original, with 32 times more RAM and an SD card for basically unlimited storage.

Using 30 Year Old Microcontrollers

July 24, 2013 by Brian Benchoff 29 Comments

chips

Like a lot of electronic tinkerers, [Andrew] has a lot of ancient components floating around his parts bin. His latest rediscovery in his cornucopia of components are a few Intel MCS-48 microcontrollers, dating back to 1977. Along with a few old EPROMs, [Andrew] decided it was worth getting these chips running again, if only for a historical curiosity.

[Andrew]’s had a few Intel 8035L microcontrollers on his hands, but this particular model of MCS-48 micros lacks any way to store code. This is where the EPROMs come in. With a modern EPROM programmer, [Andrew] was able to write some code to the extremely common for their vintage 27256 EPROMs. Erasing them, though, does require a UV lamp.

With the ROM programmed and the chips connected, [Andrew] was able to make a simple blinking LED circuit. Sure, it’s the simplest thing you can do with a microcontroller, but [Andrew]’s off to a great start in his explorations of older hardware.

Anachronistic Hard Drive For The Apple II

July 23, 2013 by Brian Benchoff 12 Comments

applefile

Not wanting too many disks lying around his Apple II battlestation, [NeXT] started looking into hard drive solutions. There is the old-time solution – a ProFile hard drive initially designed for the Apple /// and Lisa, but those are rare as hen’s teeth, and just as expensive as newer Compact Flash adapters. [NeXT] had another option – SCSI, with an adapter card, but most of the SCSI devices of the era didn’t fit in with the cool ‘stackable’ aesthetic of AII peripherals.

With a bit of Bondo and some paint, [NeXT] modded an old dual disk drive into a retro-looking hard drive perfect for storing and running hundreds of old games.

[NeXT] began his build by taking an old Apple DuoDisk (the two-disk drive seen above) and Bondoing over the holes in the front. A drive activity light was added above the Apple logo, and the old drives saved for another day. Inside the new enclosure, an old 40MB hard drive, tested on a Macintosh SE/30, was installed along with a small power supply for the drive. With a few custom SCSI cables, the drive will be ready for it’s grand debut. We think it looks awesome just sitting there, and is sure to be the pride of [NeXT]’s collection.