之前用U盘往emmc里写入过
dd if=/dev/zero of=/dev/mmcblk0p1 bs=1024 count=1024
重启后 机顶盒按电源键 灯不亮了
现在连接ttl，用终端跑马显示这个：
Bootrom start
Boot Media: eMMC (Default Speed)
Boot head format invalid.
STATE:0x00000000 0x00000000 0x00000000 0x00000000
这种情况也没法得到ip地址
尝试用串口烧录emmc，提示下面的错误：
串口已经连接，请给单板上电，若已经上电，请断电后重新上电。
Bootrom start
Boot Media: eMMC (Default Speed)
############Timeout error.
Failed to send the head frame.
Failed to send the auxiliary code data.
Boot head format invalid.
STATE:0x00000000 0x00000000 0x00000000 0x00000000
Failed to send the auxiliary code data.It may be caused by the following reason:
- The secure boot function of Hi3796M V200, Hi3716M V450, and Hi3796A V200 chips is enabled, but the auxiliary code area is not correctly signed
- If verification of multiple tables is not supported, the tables may be incorrect or the DDR training may be faulty due to DDR exceptions. As a result, the DDR cannot be used.
Failed to download fastboot!
这是已经变砖头了吗？
还能抢救一下吗？
