1284p-pu programming problem ( without bootloader) [Solved]

but why if I use
sudo avrdude -c avrispv2 -p m1284p -P /dev/ttySA0 -t -v -v

i see

avrdude: Device signature = 0x1e9705
avrdude: safemode: lfuse reads as FF
avrdude: safemode: hfuse reads as DC
avrdude: safemode: efuse reads as FD

but when i enter in terminal mode and type command sig

the result is

Device signature = 0x000000