How the Game Genie Works

Those of us old enough to remember blowing into cartridges will probably remember the Game Genie – a device that plugs in to an NES, SNES, Sega Genesis, or Game Boy that gives the player extra lives, items, changes the difficulty, or otherwise modifies the gameplay. To someone who doesn’t yet know where the 1-up is in the first level of Super Mario Bros., the Game Genie seems magical. There is, of course, a rhyme and reason behind the Genie and [The Mighty Mike Master] put together a great walkthrough of how the Game Genie works.

There are two varieties of Game Genie codes – 6-character codes and 8-character codes. Both these types of codes translate into a 15-bit address in the game ROM (from 0x8000 to 0xFFFF for the 6502-based NES) and a data byte. For the 6-character codes, whenever the address referenced by the Game Genie code is accessed, a specific data byte is returned. Thus, infinite lives become a reality with just a 6-character code.

Some games, especially ones made in the late years of their respective systems, use memory mapping to increase the code and data provided on the cartridges. Since areas of data are constantly being taken in and out of the CPU’s address space, merely returning a set value whenever a specific address is accessed would be disastrous. For this bank-switching setup, the Game Genie uses an 8-bit code; it’s just like the 6-bit code, only with the addition of a ‘compare’ byte. Using an 8-bit code, the Game Genie returns a specific byte if the compare bytes are equal. Otherwise, the Genie lets hands off the original data to the CPU.

Of course, all this information could be gleaned from the original patent for the Game Genie. As for the circuitry inside the Game Genie, there’s really not much aside from an un-Googleable GAL (general array logic) and a tiny epoxied microcontroller. It’s an amazingly simple device for all the amazement it imbued in our young impressionable minds.

Continue reading “How the Game Genie Works”

Handheld Console Build-off


The above pic isn’t a new Wii U controller from Nintendo – it’s the product of the 2013 Portable Build-Off Challenge over at the Made By Bacteria forums. Every year the Bacman forums hold a contest to build the best portabalized console, and like every year this year’s entries are top-notch.

One of the more interesting projects this year is a handheld PlayStation 2 put together by [Gman]. It uses a PS2 Slim motherboard and a dualshock 2 controller along with a 4-inch screen to stuff an entire PS2 into a convenient handheld gaming device. [Gman] ditched the CD drive and opted to play games off the USB drive, a clever substitution that really reduces the size and power consumption.

In our humble opinion, the best looking console mod is the one shown above by [Bungle]. It’s a portable GameCube stuffed inside a handmade case with a WiiKey Fusion that allows games to be played off an SD card. It’s an amazing build, and we can only hope [Bungle] will make a few molds of his case.

The entire contest has an incredible display of console modding expertise, and is well worth a look.

Mario plays piano with a little help from Raspberry Pi


[David] has created his own live robot band to play live versions of the music and sound effects of NES games. Most of us who grew up in the 80’s and 90’s have the music of Nintendo games burned into our brains. While there have been some amazing remixes created over the years, [David] has managed to do something truly unique. Armed with an emulator, some software prowess, and a pair of Raspberry Pis, [Dave] created a system that plays game music and sound effects on analog instruments. A Yamaha Disklavier player piano handles most of the work through a connection to a Raspberry Pi. Percussion is handled by a second Pi.  Snare drum, wood block, and tambourine are all actuated by a custom solenoid setup.

The conversion process all happens on the fly as the game is played. [Dave] says the process has about ½ second of lag when played live, but we’re sure that could be fixed with some software tweaks. Continue reading “Mario plays piano with a little help from Raspberry Pi”

Functional NES controller coffee table

For reddit user [the_masked_cabana], button mashing has taken on a whole new meaning.  His gigantic NES controller coffee table makes it hard to punch in the Konami code without breaking a sweat.

Even before discussing the electricals, this is one impressive build.  Each component was cut from multiple layers of MDF and assembled with screws, glue, and putty.  Once they were sanded smooth, he used layers of carefully applied Krylon paint to achieve a plastic sheen that is remarkably faithful to its 5″ counterpart.  For the more precise lettering, custom cut vinyl stickers did the trick.

Of course, looking the part is only half the battle.  Tearing apart an original NES controller, he soldered wires to the button connections and ran them to eight arcade style buttons located under the replica button covers.  A collection of bolts and springs keep everything aligned and produce the right kind of tactile feedback to the user.  A removable cable in the back provides the connection to the console.

If a four foot NES controller isn’t practical enough for you, he also added some storage space in the base and a removable glass cover that converts the controller into a coffee table.  For more details on the build, check out the reddit discussion.  You can also find an eerily similar working NES controller table in this geeky coffee table roundup from five years ago.

SNESoIP: It’s exactly what it sounds like


Here’s a cool hack for those of you wishing to play some retro multiplayer SNES games online!

[Michael Fitzmayer] is a resident hacker at shackspace; der hackerspace in StuttgartHe’s come up with this clever little ethernet adapter network-bridge that can share local controller-inputs over the internet. The entire project is open-source, and readily available on github. It’s still in the early stage of development, but it is already fully functional. The firmware is small and will fit on an ATmega8, and by the looks of the component list it’s a fairly easy build.

He’s even integrated a switch mode (hold B and Y during boot), which avoids trying to figure out which controller will be player one! After all, don’t you remember untangling the controller cords, trying to figure out which one is which?

We know you had a favorite controller and would give the other “crappy” one to your guest.

Example video is after the break.

Continue reading “SNESoIP: It’s exactly what it sounds like”

NES: Nixie Entertainment System


[Bradley W. Lewis] is no stranger to Nixie clock builds, and he felt his latest commission was missing something. Instead of merely mounting the Nixie clock into a case resembling an NES console, he goes full tilt and makes it into an NES console emulator. After some work on the milling machine, a wooden box has room to squeeze in a few new components. [Bradley] originally planned to mount only an Arduino with an ArduNIX shield to handle the Nixie clock, but the emulator demands some space saving. Flipping the Arduino on its side freed up plenty of room and the shield still easily connects to the adjacent Nixie tube board.

A Raspberry Pi serves as the console emulator and was mounted close to the side of the case to allow access to its HDMI port. The other ports from both the Arduino and RasPi stick out of the back, including an extension to the Pi’s RCA video out and buttons to set both the hour and minutes of the clock. The two surplus NES buttons on the front of the case control power to the RasPi and provide a reset function for the Nixie clock.

If that isn’t enough Nixie to satisfy you, check out the WiFi Nixie counter.

E-cigarettes, powered by an NES controller


Electronic cigarettes are all the rage these days, and as with any new electronic bauble, someone is eventually going to stuff it in some old NES hardware. The NES controller e-cig has been done before, but [mastblast09]’s controller mod is one of the best ones around.

A bit of background before we dig into this: e-cigarettes are just any other *cough cough cough* vaporizer you might find, but instead of turning a solid into a vapor, these guys turn a nicotine-infused liquid into a vapor. As e-cigarettes are a bit more legal than some other magic boxes, there is, of course, an amazing amount of options out there for those that partake.

[Mastblast09] is using an off-the-shelf e-cig controller and charger board carefully placed them in a hollowed out NES controller. With the help of a few tact switches he made the B button on the controller light up the coil and the up and down switches change the wattage.

The real treat in this build is the addition of a very small LED voltmeter. With this, [mastblast09] can check out the voltage of his NES e-cigarette under load, a big help if you’re trying to perfect the perfect vape while the battery is under load.