# Additional setup

## Change the default root password

By default, root users can log in using the `oelinux123` password. To change the password, do the following:

1. Log in as a `root` user.
2. To change the `root` password, run the following command:

> 
> 
> passwd
>     Copy to clipboard

Note

This command will prompt you to enter a new password.

3. Log out using the `exit` command.
4. Log in as `root` using your new password.

## Create a non-root user account

Note

By default, you can log in as the `root` user.

1. To create a non-root user account, run the following command in the shell.

> 
> 
> adduser guest
>     Copy to clipboard

Note

This command will prompt you to enter a new password.

2. Log out using the `exit` command.
3. Log in to the shell using your new user account credentials.

## Install QUD on Linux host

The QUD is installed on the Linux host to detect the RB3 Gen 2 device.

Note

For Ubuntu 22.04, you might encounter an issue while installing QUD. To ensure a successful installation, you may need to enroll the public key on your Linux host. For additional details, follow the steps provided in the README file available in the `/opt/QUIC/sign/signReadme.txt` directory.

1. To clone the Git repository, run the following commands:

sudo apt install git
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sudo git clone https://github.com/quic/quic-usb-drivers.git
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cd quic-usb-drivers
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2. To provide executable permissions to the file, run the following
command:

sudo chmod +x QcDevDriver.sh
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3. To install the QUD driver, run the following command:

sudo ./QcDevDriver.sh install
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4. To detect the device, run the following command:

lsusb
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    **Sample output**

Bus 002 Device 099: ID 05c6:901d Qualcomm, Inc. QCM6490\_e05d8b80

## Install ADB

Some of the Qualcomm proprietary tools require an Android Debug Bridge
(ADB). ADB is a command-line tool that enables communication with the
RB3 Gen 2 device. The `adb` command facilitates various device
actions, such as debugging, capturing kernel logs, and pushing
applications and files to the device.

1. [Install QUD on Linux host](https://docs.qualcomm.com/doc/80-70015-253/topic/additional_setup.html#task-e5v-jvg-r1c).
2. Run the following command on the Linux host:

sudo apt install git android-tools-adb android-tools-fastboot wget
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3. To verify the adb version on the Linux host, run the following
command:

adb --version
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    **Sample output**

Android Debug Bridge version 1.0.39
Version 1:8.1.0+r23-5ubuntu2

### Connect to ADB

1. Using the USB Type-C cable, connect the RB3 Gen 2 device with the
host system. Ensure that the device is listed as an ADB device.

adb devices
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    **Sample output**

List of devices attached
68f592a device
2. To enter the shell, run the following command:

adb shell
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    **Sample output**

#

## Update USB and Ethernet controller firmware

If you encounter USB or Ethernet connectivity issues on the RB3 Gen 2 device, a firmware update to the USB controller may be a solution.

**Prerequisites**

- Ensure that the software is upgraded as described in [Update Software](https://docs.qualcomm.com/doc/80-70015-253/topic/set_up_the_device.html#ubuntu-up-sw) before updating the Renesas firmware.
- The device should be connected to the Linux host through the USB Type-C cable.

**Procedure**

Note

The following procedure is applicable only to an Ubuntu 22.04 host. If you are using a Windows or Mac host, set up an Ubuntu virtual machine by following the instructions described in the [Virtual Machine Setup Guide](https://docs.qualcomm.com/bundle/publicresource/topics/80-70015-41/getting-started.html).

1. To download the firmware, register and log in to the Renesas website at [https://www.renesas.com/](https://www.renesas.com/). Once logged in, you can access the firmware from the following [link](https://www.renesas.com/us/en/products/interface/usb-switches-hubs/upd720201-usb-30-host-controller#design_development).
2. To create the `usb_fw.img` image and copy the USB firmware, run the following commands on the Linux host machine:

dd if=/dev/zero of=usb_fw.img bs=4k count=240
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mkfs -t ext4 usb_fw.img
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mkdir usb_fw
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sudo mount -o loop usb_fw.img usb_fw/
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sudo cp -rf renesas_usb_fw.mem usb_fw
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sudo umount usb_fw
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3. To start the device in Fastboot mode, run the following commands:

adb root
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adb shell
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reboot bootloader
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4. When the device is in Fastboot mode, run the following command:

fastboot devices
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    **Sample output**

7dc85f5e         fastboot
5. To flash the `usb_fw.img` image to the device, run the following commands:

fastboot erase usb_fw
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fastboot flash usb_fw  usb_fw.img
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Last Published: Oct 31, 2025

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