Analysis

How to get information about how Streamdecks might work:

I used Wireshark to read the USB traffic that is caused by using the original software for streamdecks. By changing any settings or key bindings in this program you will log packets whose analysis will allow guesses about the packet structure and required fields.

Streamdeck Mk.2 USB traffic analysis

Streamdeck Original Software Commands

Length of 32 bytes Ends often with

0x61 0xc0 0x24 0x01 0x00 0x00 0x00

Set Brightness

0x03 0x08 [brightness as percentage (1B)] 0x6b 0x01

Set Standby Timeout

never:  0x03 0x0d 0x00 0x00
5min:   0x03 0x0d 0x2c 0x01
15min:  0x03 0x0d 0x84 0x03
30min:  0x03 0x0d 0x08 0x07
1h:     0x03 0x0d 0x10 0x0e
2h:     0x03 0x0d 0x20 0x1c

cmd:    0x03 0x0d [timeout in secs (2B le)]

Set rotation

1. Sends brightness cmd
2. Sends standby cmd
3. Sends standby cmd again?

Set image

0x02 0x07 [key index (1B)] [is last package (1B)] [body length (2B le)] [package index (2B le)] [image as JPEG max. 1016B]
Total and exact(!) length of 1024B required.

Streamdeck Button Handling

• Sends update on any action (key press and release)
• always sends 512 Bytes
• keys begin with an offset of 4 bytes
• 0x01 if key pressed and 0x00 if not pressed
• ordered ltr ttb