- We have one set of 22 packets starting @ 123, incrementing wIndex in ascending order with fix values : 0x0a, 0x00, 0x2e
- Then, another set of 20 packets starting @ 186, with no particular incrementing order, but are paired by two (stereo ? while loop ? probably stereo groups.). Missing indexes are 2 and 3.
0x40 : 26 (0x1a) | SetGain() / hwWriteLedAndPga()
Note: Those could be some initialization first, followed by user-saved gain value if different. This should be tested and verified with TotalmixFX and wireshark.
TODO: Find the function sending those guys !
Conclusion: The first set always send the same values. This must be some init. The second is the application of the user values from TotalMix. These are sent only if they are different from the "init". Nice guess, dude.
0x40 : 16 (0x10) | Set Sample Rate (pkt 2/2)
| Set Clk src, single speed, coax AES/SPDIF
| UNKNOWN - sent by hwInitHardware() from FirefaceUSB.kext
0xc0 : 16 (0x10) | UNKNOWN - hwGetRate() from FirefaceUSB.kext
0xc0 : 17 (0x11) | UNKNOWN - hwGetRate() from FirefaceUSB.kext
0x40 : 18 (0x12) | Set in / pb / output volume
0x40 : 19 (0x13) | Hardware Mute
0x40 : 20 (0x14) | Hardware unMute
0x40 : 21 (0x15) | Set Loopback on output
0x40 : 22 (0x16) | UNKNOWN - sent by hwInitHardware() from FirefaceUSB.kext
0x40 : 23 (0x17) | Set +48v / PAD / Hi-Z
0xc0 : 25 (0x19) | UNKNOWN - de_RME_driver_USBAudioUserClient::sUserClientReadStatus() from FirefaceUSB.kext
0x40 : 26 (0x1a) | Always from hwWriteLedAndPga() function (Gain, output vol)
0x40 : 27 (0x1b) | Set Sample Rate (pkt 1/2)
0xc0 : 28 (0x1c) | Get firmware version
0x40 : 32 (0x20) | UNKNOWN - sent by hwInitHardware() from FirefaceUSB.kext
Observations avec Wireshark.
- on récupère la version du firmware : hwGetRevision() TODO
Toutes les 2ms : intéroge l'interface sur sa fréquence d'échantillonnage hwGetRate() TODO