UsbXlater, DualShock 4, PlayStation 4, Weekly Report Dec 15, 2013

I haven’t worked on the firmware for the UsbXlater for a while. This is because I really want it to work on the PlayStation 4 by spoofing the DualShock 4, but after some heavy investigation. It seems like this is impossible (in the sense of spoofing).

On the DualShock 4 circuitry, I have recently found the UART (aka serial port) pins for the Bluetooth module’s HCI (host controller interface). I used my logic analyzer to capture the data from the HCI. The results are posted on my wiki page about the DualShock 4, along with the pcap file with the entire capture.

The PlayStation 4 does not seem to accept input through USB. I did get UsbXlater entirely working and replicating the behaviour of a real DualShock 4, but the PlayStation does not respond. The Bluetooth connection is always active during this time.

Over Bluetooth, it seems that the L2CAP packets that are sent containing the report contains 4 bytes at the end that appears to be random. This could mean it’s a checksum or a hash. Update: it’s a CRC32, with a standard initial value. It’s easy to generate and I’ve already tested it on my sample capture data, so that’s good news. Credit goes to Matlo from GIMX

I do have a new version of the UsbXlater hardware that I can get assembled next week. It will emulate button presses on the DualShock 4 directly using electrical signals connected to the buttons themselves, instead of digitally through spoofing data streams.

I am aware that CronusMax has a “proof of concept” video of his hardware working on the PS4, but that video is a fake, what he did is program it to act as a HID keyboard, which only works in the menus. This is why the video does not show gameplay and why he does not plain outright say that it will be supported. Everybody who is making a device similar to XIM or Cronus or Eagle Eye Converter or UsbXlater is facing the exact same difficulties I am facing. I am disappointed in Cronus because the video’s purposes is probably to drive up pre-orders for people who are hoping for PlayStation 4 support which might never come.

3 thoughts on “UsbXlater, DualShock 4, PlayStation 4, Weekly Report Dec 15, 2013

  1. HC

    As a Humanities major who somehow wound up working in the tech sector, I am at once baffled by the concepts at play here and totally impressed by the work you’re doing with this project – classy people like you are truly responsible for the liberation of modern technologies, so a tip of the hat to you, good sir, and may you find success in this endeavor!

  2. Paul

    This is super interesting, too bad that it seems nothing has developed since?
    It own a PS4 and would love to test and help, I worked quite a bit with MCUs so far so I might be of help.

    1. Admin Post author

      I used the opportunity to learn about Bluetooth and USB and the security aspects. I am more interested in gaining the skills, instead of “ironing out bugs”, there’s too much software work. Recently I’ve moved on to other interesting things instead, like 3D printing stuff and quadcopter stuff. Sorry.

      For less money you can buy a complete solution from people who actually have a job making similar things, like the XIM4.


Leave a Reply

Your email address will not be published. Required fields are marked *