📝 Add Stream Deck XL documentation.

Docs/Stream Decl XL.md

@@ -0,0 +1,172 @@
+# Stream Deck XL
+
+The Stream Deck XL from Elgato has 32 configurable buttons, each sporting an individual display, arranged in a 8x4 layout.
+
+Internally, as seen in the multiple teardowns, the device uses a single screen for all buttons.
+
+The device does not have much intelligence outside of decoding JPEG and drawing images in the proper part of its internal framebuffer.
+Everything has to be controlled from a client application.
+
+## HID Protocol
+
+The device uses report IDs from `01` to `0C` to communicate.
+All feature reports are 32 bytes long, including the report ID.
+All data is presented in little endian form.
+
+### Input report `01` - Device events
+
+This report is 512 bytes long.
+
+```
+01 00 <ButtonCount:U8> <Unknown:U8> <IsButtonDown:U1[]>
+```
+
+Each time the state of a button changes, the device should send this packet including the status of all buttons.
+
+### Output report `02` - Packet writes
+
+This report is 1024 bytes long. It is split in multiple commands used to transfer data to the device.
+
+#### Command `05` - Firmware update
+
+```
+02 05 <SectorIndex:U8> <IsFinalPacket:B8> <IsLastSector:B8> <PacketIndex:U16> <PacketLength:U16> 02 <Zero:U8[6]> <Data:U8[]>
+```
+
+This command is similar to the image write commands, but the data is written in 4k sectors.
+So, each write for one sector is composed of 4 transfers of 1008 bytes followed by one transfer of 64 bytes, except for the last sector written.
+
+Impossible to know for sure, but the fixed `02` byte might indicate a specific firmware to update.
+As there are up to three versions returned, one can assume that there are things like bootloader firmware, etc.
+
+There does not seem to be any command to prepare or complete a firmware update, except for the writes themselves.
+The firmware transfer is completed by a device reset, then the device should restart. (In order: Set sleep timer; Reset; Set brightness)
+
+Firmware 1.01.000 end is 115272 bytes.
+
+#### Command `07` - Write button image data
+
+```
+02 07 <KeyIndex:U8> <IsFinalPacket:B8> <PacketLength:U16> <PacketIndex:U16>
+```
+
+#### Command `09` - Write screensaver data
+
+```
+02 09 08 <KeyIndex:U8> <IsFinalPacket:B8> <PacketIndex:U16> <PacketLength:U16>
+```
+
+### Feature report `03` - Write - Device configuration
+
+#### Command `02` - Reset
+
+```
+03 02
+```
+
+This command will reset the display and put the device in screensaver mode.
+
+#### Command `05` - ???
+
+Sent when the software is starting up. Possibly an initialization command that would switch the screen out from sleep mode.
+
+#### Command `06` - ???
+
+#### Command `08` - Brightness
+
+```
+03 08 <Brightness:U8>
+```
+
+#### Command `0D` - Idle Sleep Timer
+
+```
+03 08 <Duration:U32>
+```
+
+The idle sleep timer is defined in seconds.
+
+### Feature report `04` - Read - Some firmware version
+
+```
+04 <Unknown:U8> <Unknown:U8> <Unknown:U8> <Unknown:U8> <Unknown:U8> <Version:ASCII[8]>
+```
+
+Version numbers use the format `0.00.000`.
+
+Known version numbers are:
+
+* 0.01.007
+
+### Feature report `05` - Read - Main firmware version
+
+```
+05 <Unknown:U8> <Unknown:U8> <Unknown:U8> <Unknown:U8> <Unknown:U8> <Version:ASCII[8]>
+```
+
+Version numbers use the format `0.00.000`.
+
+The version number returned by this command is the one displayed in the official software.
+
+Known firmware version numbers are:
+
+* 1.00.012
+* 1.01.000
+
+### Feature report `06` - Read - Serial number
+
+```
+06 <SerialNumber:ASCII[12]>
+```
+
+### Feature report `07` - Read - Some firmware version
+
+```
+07 <Unknown:U8> <Unknown:U8> <Unknown:U8> <Unknown:U8> <Unknown:U8> <Version:ASCII[8]>
+```
+
+Version numbers use the format `0.00.000`.
+
+Known version numbers are:
+
+* 1.00.008
+
+### Feature report `08` - Read - Device information
+
+```
+08 <RowCount:U8> <ColumnCount:U8> <ButtonImageWidth:U16> <ButtonImageHeight:U16> <FramebufferWidth:U16> <FramebufferHeight:U16> <Unknown:U8> <Unknown:U8> <Unknown:U8> <Unknown:U8> <Unknown:U8> <Unknown:U8> <Unknown:U16> <Unknown:U16>
+```
+
+Example:
+
+```
+08 04 08 6000 6000 0004 5802 02 00 01 04 04 00 0000 0000 0000000000000000000000
+```
+
+### Feature report `09` - Read - Device total uptime
+
+```
+09 <Unknown:U8> <Unknown:U8> <Unknown:U8> <Unknown:U8> <Duration:U32>
+```
+
+Example values for the unknown bytes: `04 00 02 00`
+
+### Feature report `0A` - Read - Sleep timer
+
+```
+09 <Unknown:U8> <Duration:U32>
+```
+
+Example:
+
+```
+0A 04 201C
+```
+
+### Feature report `0B` - Read - ???
+
+This seems to return a single byte. (`02`)
+
+### Feature report `0C` - Read - ???
+
+This seems to return a single byte. (`08`)

Exo.sln

@@ -40,6 +40,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Docs", "Docs", "{08303426-8
 		Docs\Razer DeathAdder Platform 3.md = Docs\Razer DeathAdder Platform 3.md
 		Docs\Razer DeathAdder V2 Pro.md = Docs\Razer DeathAdder V2 Pro.md
 		Docs\Razer Mamba Chroma.md = Docs\Razer Mamba Chroma.md
+		Docs\Stream Decl XL.md = Docs\Stream Decl XL.md
 		Docs\Useful Bits.md = Docs\Useful Bits.md
 		Docs\ViewSonic VP2785-4K.md = Docs\ViewSonic VP2785-4K.md
 	EndProjectSection