Debug串口

看内核启动log信息，当机器无法启动可以判定问题

开启串口登陆

• sudo raspi-config

开启内核log

• cat /boot/cmdline.txt

  console=serial0,115200 console=tty1 root=PARTUUID=d3269df4-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait quiet splash plymouth.ignore-serial-consoles modules-load=dwc2,g_ether dwc_otg.lpm_enable=1
• 修改第一个console：console=ttyS0,115200
• 移除第二个console：console=tty1
• 移除quiet字段
• cat /boot/cmdline.txt

  console=ttyS0,115200 root=PARTUUID=d3269df4-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait splash plymouth.ignore-serial-consoles modules-load=dwc2,g_ether dwc_otg.lpm_enable=1