CZ-A servos, who knows?

as I understood, does this mean that the motor's own encoder should be connected in both directions(from CN1), both to the driver and to the 7i77?

No, the motor encoder connects to CN2. Look at page 13 of the manual linked in a previous post.

yes ok , it confused me because my driver is different (cn3 is the encoder for the motor and cn 2 is the I/O port on the driver) thank you