UCSD Robocar Jetson Nano Configuration
Introduction
The NVIDIA Jetson Nano in this document is also referred as JTN.
To learn more about the JTN, you can check out the NVIDIA documentation sources Getting Started, Jetson Download Center, and the documentation for usage on DonkeyCar.
!!! info " In general for this course if you are using a computer with a Linux distribution like Ubuntu you will have an easier time installing the necessary Artificial Intelligence framework. Linux uses a file format that is not easily read in an Apple MacOS or MS Windows computer. If you need to modify files in the \(\mu\)SD card formatted for Linux, e.g., a disk partition that uses Ext4 format, you should ask a colleague first if they have a Linux PC, then Tutors or TA for help.
Every Team is expected to try installing the necessary software based on these instructions using the \(\mu\)SD image, not the recovery image. And every member of the team needs to participate during the lab embedded linux hands-on exercise. The same SBC (JTN) can be used at the class by several users without the need to connect a monitor and a keyboard to it. It is part of your learning in the course to get familiar with Embedded Linux, Head-Less Single Board Computers (SBC) like the JTN, terminal running in a PC, SSH, and remotely installing software in a SBC.
If you run out of time, based on instructor’s set deliverables, or your \(\mu\)SD card gets corrupted, you can use the recovery \(\mu\)SD card image that has all the software pre-installed. On the 10-UCSD Robocar ECE & MAE 148 document there is a link to a recovery \(\mu\)SD card image.
Flashing microSD card for the Jetson Nano
From your PC let's prepare (flash) the microSD card (\(\mu\)SD card). Make sure your computer can access the Internet. If you are using one of our WiFi Access Points in one of the labs, or at one of the tracks, the first device that connects to the WiFi Access point and try to access the Internet, will need to accept the UCSD Wireless Visitor Agreement, just like when you are connecting to UCSD’s Visitor WiFi. In fact you are basically connecting to the Internet via the UCSD’s Visitor WiFi.
Software Installation
Etcher can use Zipped files, you don’t need to Unzip the image file if you are using Etcher. Ignore if your Windows or Mac computer tells you it can not ready the \(\mu\)SD card. The \(\mu\)SD card will be used on the JTN running Linux. It uses a file format that Windows and Mac don’t know about unless you use specialized software to do that. You don’t need it. If you are using Linux or MacOS command lines to write the disk image to a \(\mu\)SD card, you may need to extract the file first.
Download the UCSD Jetson Nano Developer Kit \(\mu\)SD Card Image here.
Once you have the image, install Etcher to be able to write the disk image to a microSD card here.
Using the image we are providing as a starting point has some advantages with some pre-configuration. For example, it won't require a monitor and a keyboard connected to the JTN to get you started.
Writing an image to a \(\mu\)SD card
Connect a \(\mu\)SD adapter to your PC.
- Insert the provided \(\mu\)SD card (64 gigabytes) into the \(\mu\)SD adapter.
- Install and run Etcher.
- Start Etcher, choose the Zipped file with the Disk Image you downloaded, pay attention when choosing the drive with the \(\mu\)SD card on it (e.g., 64 gigabytes).
- Write the image to \(\mu\)SD card.
- Eject the \(\mu\)SD card from your PC first using the procedure for your PC Operating System (e.g., eject drive)
- Then insert the \(\mu\)SD card into the JTN \(\mu\)SD card slot. Note this is a push-in-to-lock and push-in-to-unlock the \(\mu\)SD card. Please do not pull the \(\mu\)SD card out of the slot before unlocking it, otherwise you may damage your JTN and or \(\mu\)SD card.
Powering on the JTN
The preferable way to power the JTN is with the provided 5V 4A power supply; it has a barrel connector that plugs into the JTN. You need to place a jumper connector at J48, there is a text label close to it that says ADD JUMPER TO DISABLE USB PWR.
For the initial configuration you don’t have to use the 5V 4A power supply. If you are not using the provided power supply for the initial configuration, you need to remove the jumper located above the JNT power connectors to allow it to be powered by the uUSB cable. Please save the jumper. You can leave it in place connected to one of the pins of J48.
Power on the JTN by connecting the power supply to a power outlet and the barrel jack into the barrel port on the Jetson.
Note
Give the Jetson a minute or two to boot and load its software and the fan may not work until you install the software later in these instructions.
Wired communication with the JTN
We will use the command line to access the Jetson Nano (JTN) using a secure shell (SSH). Don’t worry, if you are not familiar with terminals and using command lines, you will master it in this class. Mastering these will be a good skill to have and another mention in your resume.
The Linux OS running on the JTN enables two protocols of communication: Serial Communication and SSH. Both use a local network interface with TCP/IP over the USB cable. By using a micro USB cable between the JTN and the PC, you can communicate with the JTN. On the PC, you need to use software to enable serial communication or SSH. e.g., Serial Communication - screen on Linux or MacOS. CoolTerm is another option that runs on Linux, MacOS, and MS Windows. SSH is natively supported on Linux and MacOS. MS Windows 10 or later supports SSH too.
Note
Your JTN should have a WiFi / Bluetooth network interface and antennas already installed on it. If not, please contact the Tutors or TAs.
SSH Communication (via USB connection)
Connect a \(\mu\)USB cable between the JTN and your PC. Then, from a terminal, run:
Or:
The default UserID and password is:
Username: jetson
Password: jetsonucsd
Serial Communication
If needed, install a software called screen on your host or virtual Linux computer and/or update it.
Or you can install coolterm, or use any terminal emulator software you have. On my computer the JTN plugged in using the uUSB cable shows up as /dev/ttyACM1. Log-in info when doing a serial connection is the same as the SSH connection
The command line to connect in a Linux terminal is:
Wireless communication with the JTN
After connecting to the JTN via USB connection, let's configure the JTN to connect to a WiFi Access Point. Using SSH via USB connection or using the serial communication software log into the JTN.
First, let's make sure the network service is running.
Accessing WiFi networks
To list the available WiFi networks:
If the WiFi Access point that you want to connect is not initially listed try rescan to refresh the list. If after several tries the network still does not show, try rebooting by typing sudo reboot. After your machine has restarted:
Connecting to a WiFi network
We have bridged WiFi access points. Try to stay in the 5GHz network. The command to connect he JTN to an access point is
Here are the WiFi access points we use:
ssid="UCSDRoboCar5GHz"
password="UCSDrobocars2018"
ssid="UCSDRoboCar"
password="UCSDrobocars2018"
ssid="SD-DIYRoboCar5GHz"
password="SDrobocars2017"
ssid="SD-DIYRoboCar"
password="SDrobocars2017"
So, to connect, an example command could look like:
Get IP address of JTN
After connecting the JTN to a WiFi Access Point, let's find out the IP address the JTN is getting from the network so we can connect to it remotely.
In a terminal:
You should see some output that contains the following line:
Note
Your IP address may be slightly different. It's important to use the corresponding inet IP address output onto your screen when configuring your JTN.
In the future, to connect to a new Access Point you may have to repeat these steps using a \(\mu\)USB cable connected between your PC and the JTN.
Helpful Hint: You can add your phone as an Access Point so you always have a backup connection to your JTN. If you have your phone with you, you can connect to the JTN and then add another WiFi using SSH.
SSH communication (via WiFi)
Connect your PC to the JTN using WiFi (using example IP address from above) then enter the username and password.
Update WiFi power settings
Lets turn off the power saving for the WiFi device.
If your SSH connection is slow or lagging, make sure you have the power saving on the WiFi disabled.
Now let's install a small text editor called nano.
Lets make the change on the WiFi power saving settings persistent. We need to edit a file.
In the file, change
to
System Settings
Now lets change the name of the JTN (host name) and password of the JTN. We will configure the name of the JTN based on your Class xxx and Team yy. Hostname ucsdrobocar-xxx-yy where xxx-yy is your class and team number, ex: 148-05, 190-01, 190-TA1, 190-TA2
Example: ucsdrobocar-148-05 for Team 5
To see your current computer information:
insert screenshot
Changing your hostname
Replace xxx-yy as shown above with your class name and team number.
Then there is one more place to change the hostname:
insert screenshot
Change the name jetson here or any other name it may have for your JTN, for example
When making edits using nano, to save the file, first press Ctrl+O to write out your changes. Press Enter to save them under the same filename, and then press Ctrl+X to exit.