Unable to see device under ls /dev/cu.usbmodem* in force recovery mode

Hello, after my initial login my nano is unable to boot or hold power for more that a couple seconds.

In an attempt to solve this issue I have put my device into force recovery mode, this keeps the light on. But nothing shows up under ls /dev/cu.usbmodem*

What is the best way to get this nano working? I tried to reflash the sd card, nothing changed.

Now that I have my force recovery pins in and the light is staying on, how can I actually interact with the device to find out why it’s not booting?


first, you have to know that bootloader resides in the QSPI memory on your Jetson Nano module, and if it somehow gets corrupted, the situation will never change no matter how many times you flash the SD card with tools like Etcher. It can only be fixed by flashing with SDK Manger or the script in our BSP.

I just saw you have another post and I will also answer it here, and please do not panic.

The /dev/... sort of things you mentioned is about UART connection, and it has nothing to do with force recovery mode. Also, you should use ttyUSB* for interacting with the UART on Jetson, not cu.usbmodem*.

Steps you should do now:

  1. Use a jumper or a cable to connect the FC_REC pin and the GND pin to put it into force recovery mode. Check if you can see

Bus <bbb> Device <ddd>: ID 0955: 7f21 Nvidia Corp.

with lsusb on your host.

  1. Setup UART between your device and your host PC with a TTL-USB cable, and establish connection with tools like picocom

sudo picocom -b 115200 /dev/ttyUSB0

  1. Download our L4T r32.7.3 BSP, and prepare the rootfs with the following commands

$ cd Linux_for_Tegra/rootfs/
$ sudo tar xpf …/…/${SAMPLE_FS_PACKAGE}
$ cd …
$ sudo ./apply_binaries.sh

Run sudo ./flash.sh jetson-nano-devkit mmcblk0p1 to flash the board.
Or just use SDK Manager if what I mention above is too complicated for you.

  1. If you fail to flash the device or it fails to boot up after flashing, put the UART log and the flashing log here.

Reference for how to setup cables:

Thank you for your reply, when you say:

  1. …Check if you can see
    Bus Device : ID 0955: 7f21 Nvidia Corp.

Where should I be looking? I assume once I connect the Force recovery jumper pins (9 and 10 for this model), I need to connect my nano to a computer in order to see this information.

Right now I have the jumper in Recovery with the barrel jack, the power light is on, I can do a USB connection to my mac, is there a command I can run in the terminal to see this Bus <bbb> Device <ddd>: ID 0955: 7f21 Nvidia Corp. info?


no wonder you are saying ls /dev/cu.usbmodem* as you are using a Mac… It’s lsusb on Linux.
Please grab a x86 host PC running Ubuntu 18.04 to proceed. We do not support flashing Jetson devices on Mac and Windows. (you may be able to get it done on VMes, but there may a lot of problems before you can eventually flash the device)

Right now I have a device where the light turns on for a second and turns off, I have a mac computer, is there anything I can do to get a working nano without buying some other computer?

Is there any other pathway to getting this device to do work or even communicate information at all without a new computer that doesn’t involve flashing?


if you are using an Intel Mac, then I think you can dual boot your Mac with Ubuntu to get around the need of buying a new computer. Ubuntu is the only platform we officially support for flashing Jetson devices.

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