I have just contact canaan and they say to me to buy a control board directly from their factory.
I think I have no other choice...
Anybody know how to download a firmware directly from an asic ? Maybe if it's possible this solution can work !
The firmware link for Canaan units already posted above
https://download.canaan-creative.com/The only problem is that 1246 remove the firmware from their download page I don't know why but there are two firmware available on that page before.