After reflashing, my Jetson Nano could not boot

I followed the instruction from the weblink:

The problem is that I could not boot any more after reflashing. The GUI of my Jetson Nano is shown below:

I will appreciate if you can give me some ideas, thanks!

Sorry for the late response, have you clarified the cause and resolved the issue?

Use uart to access your board and see if you can interact with the board.

If you can, then please share us the result of command “lsmod” and log file /etc/var/log/Xorg.0.log.

Thank you for your reply! Unfortunately, the problem until now was not sloved and you told me to use the uart, I can use jumper to connect the Jetson Nano like this:
Jetson Nano J41 Pin 8 (TXD) → Cable RXD (White Wire)
Jetson Nano J41 Pin 10 (RXD) → Cable TXD (Green Wire)
Jetson Nano J4 Pin 6 (GND) → Cable GND (Black Wire).
But for the another port I do not know how to connect. I just have a desktop with Ubuntu 16.04.

What do you mean another port? Aren’t you using usb-ttl cable?

Actually I do not have usb-ttl cable, when I followed the instruction: Enabling PPS on Jetson Nano.
I used the usb to connect Jetson Nano and my desktop with Ubuntu16.04 installed and then reflashed.

Yes, so now we need you to setup the uart serial console so that you can check the device log on host side.
To dump uart log, you need the usb-ttl cable and there is a tutorial in the link I posted…

Thanks! I will try to get the Usb-ttl cable thx!

Thanks for your help and I made it, I successfully reflshed the kernel but another problem occurred: when I finished the reflashing, Jetson Nano will open automatically, and when I input: ls /dev/pps* it will show: /dev/pps0 and /dev/pps1.
Unfortunately, when I opened again and input: ls /dev/pps*, only the /dev/pps0 can show in the terminal of Jetson Nano. I do not know what happened or if I have to setup some parts?
I will appreciate if you can tell me how to do it. Thanks!

What do you mean “open again”? Did you change anything during this “open again”?

I reboot the Jetson Nano and I found that when I input: ls /dev/pps* only had /dev/pps0

Under what case did you see there is pps1?

When I reflashed the kernel of the Jetson Nano via the method: Enabling PPS on Jetson Nano. and then after the jetson nano boot automatically, and I followed the instruction to input ls /dev/pps*, it shows: /dev/pps0 and /dev/pps1, when I reboot and input ls /dev/pps* it could not show /dev/pps1 any more.

So is there still any issue related to cannot boot?

No, just the issue of the /dev/pps1. I do not know whether it is the problem of device tree?

Please file a new topic for it.