Modifying a PS4 Dualshock4 Controller to Use a Mouse and Keyboard

[Mori] wanted to use his keyboard and mouse to play his favorite games on the PS4, so he decided to modify his Dualshock4 controller to feed it custom input signals.

In the heart of this build is an STM32F407 discovery board, which is connected to a USB hub. To perform this hack, [Mori] tore open the Dualshock4 controller to find the PCB traces coming from the sticks and buttons. He then used the STM32F407 and 2 Digital to Analog Converters (DACs) to create similar signals. Unfortunately for us, [Mori] only released the schematics but not the firmware. Our guess is that he had to configure the microcontroller as a USB host, enumerate the mouse/keyboard, parse the HID reports and feed the controller the corresponding inputs.
We embedded a video of the hack in action after the break.