chanelled stove with micronova PIO 050 mainboard Aux Fan implementation

[Miniteuf67]

Hi,

I’ve been testing my Micronova Etna Cayenne 16C (board PIO 050, Micronova, not Duepi) and sniffing frames in order to identify the auxiliary fan registers (Fan 2 and Fan 3 in the official stove interface).

During a manual scan (values written sequentially 0 → 5 → Auto, ~30s interval), I observed the following:

• 0x2F (write) with mirror 0x4F (read)
• 0x31 (write) with mirror 0x51 (read)

Captured sequence (excerpt):

[00:58:32] WRITE param=0x2F val=0x00 dec=0
[00:59:00] WRITE param=0x2F val=0x01 dec=1
[00:59:29] WRITE param=0x2F val=0x02 dec=2
[00:59:58] WRITE param=0x2F val=0x03 dec=3
[01:00:27] WRITE param=0x2F val=0x04 dec=4
[01:00:56] WRITE param=0x2F val=0x05 dec=5
[01:01:25] WRITE param=0x2F val=0x06 dec=6 (Auto?)

[01:01:55] WRITE param=0x31 val=0x00 dec=0
[01:02:24] WRITE param=0x31 val=0x01 dec=1
[01:02:53] WRITE param=0x31 val=0x02 dec=2
[01:03:22] WRITE param=0x31 val=0x03 dec=3
[01:03:51] WRITE param=0x31 val=0x04 dec=4
[01:04:20] WRITE param=0x31 val=0x05 dec=5
[01:04:49] WRITE param=0x31 val=0x06 dec=6 (Auto?)

--- Mirrors observed during the scan ---
[xx:xx] READ param=0x4F → values 0x00..0x06 following writes to 0x2F
[xx:xx] READ param=0x51 → values 0x00..0x06 following writes to 0x31

👉 Hypothesis (still unverified):

• 0x2F/0x4F = Auxiliary Fan 2 (set + mirror)
• 0x31/0x51 = Auxiliary Fan 3 (set + mirror)
• Coding matches the main Power register:
  0–5 = manual speed levels, 6 = Auto mode.

This is only a working assumption for now.

Thanks!