finally i managed to connect my m9s-pro with usb/ttl adapter.so i can see every time what happens when i try ro reboot or flash the tv box.so i found that it has an error

Booting Android Image at 0x01080000 ...

reloc_addr =13f4a1c0
copy done
load dtb from 0x1000000 ......
board_usb_stop cfg: 0
Uncompressing Kernel Image ... OK
kernel loaded at 0x01080000, end = 0x01f00db8
Loading Ramdisk to 13c2d000, end 13ec30ed ... OK
Loading Device Tree to 0000000013c21000, end 0000000013c2c003 ... OK
signature:
fdt_instaboot: get header err
Starting kernel ...
uboot time: 3628506 us
the ttl pins are between first and second usb of tv box .so you need to connect to pin 2 tx, pin 3 rx , and pin 4 gnd.
i use PuTTY program. you have to found the serial line of ttl adapter on the pc. in my case is com 15 the speed is 115200 and connection type serial.