Want to stream PC games to a wireless device? You’ll need something like Nvidia’s $249 Shield jacked into a PC running a GeForce GTX 650 (or higher) desktop GPU. Kind of pricey, plus the Shield’s display is five paltry inches, posing serious problems for PC games designed for bigger, higher-resolution screens. If you’re looking for an extra inch or more of diagonal real estate, there’s Nintendo’s Wii U GamePad, but now you’re stuck behind Nintendo’s walled garden with Mario, Zelda and the lot.
Or are you? On Sunday, at the hacker-themed 30th Chaos Communication Congress in Hamburg, one of the presenting groups gave a talk (noticed by Polygon) on reverse-engineering the Wii U GamePad for PC streaming. The trick: breaking the GamePad’s “encrypted and obfuscated” wireless protocols.
The effort began in earnest in December 2012 “to reverse engineer, document and implement the Wii U gamepad communication protocols on a PC.” The hackers note, “This started our long journey of soldering wires on Flash chips, reading the h.264 specification and complaining about the lack of features in most Wi-Fi drivers and devices (on all platforms, Linux and ath9k devices being the least horrible).”
In the process, the team found that Nintendo had “reinvented” the wireless protocols the Wii U uses to chat with the Wii U GamePad:
While some “journalists” reported that the Wii U gamepad is using the Miracast technology, a Wi-Fi standard, it turned out that this was never the case. Instead, Nintendo decided to reinvent four different protocols (video streaming, audio streaming, input streaming as well as a light request-reply RPC protocol), and embed them in a slightly obfuscated version of WPA2, sent over the air using 5GHz Wi-Fi 802.11n. A small ARM CPU is embedded in the Wii U Gamepad (codenamed DRC) and runs a realtime operating system to handle network communication. In the Wii U, another ARM CPU (codenamed DRH) does the same thing.
In a year’s time, the team says it managed to convert “a 32MB binary blob” into a proof-of-concept device capable of streaming video from a PC to the Wii U GamePad. The hackers call what they’ve wrought a buggy “alpha” version and warn it’s “not meant for end users,” but have a look at the presentation slides for yourself. While there’s no video of the demo, that last slide of Cloud Strife standing beside the Midgar train at the outset of Final Fantasy VII, with the Wii U GamePad logo visible on the display device — ostensibly from the PC version of the game — pretty much says it all. If you want to learn more, the group’s sharing documentation on the project here.
Check out our three-part video series on the History of Video Game Consoles. Hosted by Doug Aamoth, the series features insight from TIME senior editor Matt Vella, Kotaku’s Stephen Totilo, IGN’s Greg Miller, Sony’s Scott Rohde, and Video Games New York’s Giulio Graziani.