1.2 KiB
1.2 KiB
Ausiomixer HID Protocol
VID=0x2E8A PID=0xA541
Composite USB: CDC (debug printf) + HID (mixer reports), vendor usage page 0xFF00.
Input report (Pico → Host) — 8 bytes
| Offset | Field |
|---|---|
| 0 | report_id = 1 |
| 1 | enc1_delta (int8) — scroll selection |
| 2 | enc2_delta (int8) — selected session volume steps |
| 3 | flags: bit0=E1 SW, bit1=E2 SW |
| 4 | pot 0..100 — system master |
| 5..7 | reserved |
Output report (Host → Pico) — 64 bytes
| Offset | Field |
|---|---|
| 0 | report_id = 2 |
| 1 | session_count |
| 2 | selected_index |
| 3 | master_vol 0..100 |
| 4 | page_start |
| 5 | n_visible (0..5) |
| 6.. | slots × n_visible |
Each slot (11 bytes): vol (1) + UTF-8 name (9) + NUL (1).
Controls
| Hardware | Action |
|---|---|
| Encoder 1 | Change selected session |
| Encoder 2 | Change volume of selected session (±2% per click on host) |
| Pot GP26 | Absolute master volume |
| SW | Logged (E1/E2); reserved |
Run
- Flash
build/ausiomixer.uf2 dotnet run --project host/Ausiomixer.Host- Play audio in Windows; names appear on the ILI9341 (320×240)