DualShock 4 on Pico-W

This is a pretty crude project which brings up a Sony DualShock 4 (PS4) controller on Pico-W.

It uses a hard-coded controller MAC address (see src/bt_hid.c), that needs to match your controller.

On first boot, make sure the controller is in "pairing" mode (hold "Share" and the PS button, so the light is doing quick double-flashes).

Once paired, it's enough to just press the PS/Home button to reconnect.

Building

The DS4 has a large HID descriptor, which doesn't fit in upstream BTStack's SDP buffer, so this project submodules a fork of BTStack wich just makes that larger.

So, clone this repository, then:

cd picow_ds4
git submodule update --init --recursive
mkdir build
cd build
cmake -DPICO_BOARD=pico_w -DPICO_SDK_PATH=/your/path/to/pico-sdk ../
make

The .uf2 file will be build/src/picow_ds4.uf2

Known Issues

pico-sdk implements its own btstack makefile (see $PICO_SDK_PATH/src/rp2_common/pico_btstack/CMakeLists.txt), which means a particular pico-sdk version is only technically compatible with a single btstack version. See https://github.com/raspberrypi/pico-sdk/issues/1553 and

1.

If you run in to build issues which look related to btstack, it could be because the version this project depends on has diverged from your version of pico-sdk again.

This repo is known to build OK against pico-sdk version 6a7db34ff63345a7badec79ebea3aaef1712f374 (tag: 1.5.1).

There's two good ways to fix this, which maybe I'll do one day:

1. Upstream a configurable MAX_ATTRIBUTE_VALUE_SIZE to btstack, so that the btstack submodule could be removed here.
2. Change btstack+pico-sdk to put the make rules inside btstack instead, so that there's no implicit dependency between the two.