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README.md

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+# DP-aux emulator
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+Hardware design files for a DP-aux emulation board, designed to allow connection of PSVR2 headsets to PC.
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+![(Rendered image using Kicad2blender plugin)](render.png)
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+Prior to a March 2024 update of the PSVR2's firmware, the headset reported incorrect information via DP-aux, among others the EDID and DSC capability. A custom EDID can be set without additional hardware, however DSC options cannot - so the emulator board was born.
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+On the PCB is an RP2040 microcontroller, which decides which DP-aux requests to modify and which to pass through unchanged. To do so, a pair of SN65MLVD200A differential transceivers are used. The LVDS part of the circuit is based on [Bitec's DisplayPort Daughter Card](https://bitec-dsp.com/wp-content/uploads/2023/03/bitec_fmc_dp_rev12_sch.pdf), however, I believe my voltage divider is closer to correct for this specific chip.
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+Apart from the core DP-aux emulation circuitry, there is a programming micro-USB connector (I would have used a USB-C, but this way it cannot be confused with the PSVR2 port), orientation detection using USB-C CC pins, and a power section, allowing the board to be powered with either the programming USB port or using VBUS from the USB-Cs. Even though the board was made with specifically the PSVR2 in mind, I tried to make it as compliant as possible with a low part count and it should work well with the maximum voltage of USB-PD3.0, 21V.
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+Firmware for it was written by the autor of the iVRy SteamVR driver, a passthrough-only version of the firmware is provided in this repository for testing.
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+As of March 2024, after the update, this board is only needed for using Nvidia boards with 3rd party PSVR2 drivers. This board only modifies DP-aux traffic, it doesn't help with connecting a PSVR2 to a card without a USB-C, for an adapter for such GPUs, check out [Swyter's project](https://github.com/Swyter/psdaptwor), but note that it hasn't been tested yet.