Previously, we saw how to burn the OS onto the eMMC from an SD card. For setting up Ubuntu on BeagleBone Black, you do not need to write the OS onto the eMMC. Instead, you can boot from the SD card itself every time you power the board:

1. Installing the OS requires these steps:
   1. Download the Ubuntu arm-based Bionic version image file from this website: https://rcn-ee.com/rootfs/2019-04-10/microsd/bbxm-ubuntu-18.04.2-console-armhf-2019-04-10-2gb.img.xz.
   2. Once the image is downloaded, insert the SD card into your system and open Etcher.

1. 3. Select the downloaded image and the specific SD card location and click Flash!. You should see the output shown here:

Once completed, load the SD card into the SBC.

2. Follow these steps to load the OS:
   1. Now that the SD card is loaded, holding the boot button and power the SBC using an appropriate power supply adapter. Ensure that you hold the boot button while booting until the user LEDs begin to flash.
   2. You should see a series of loading commands. Once the OS is booted up, you should see a Terminal screen with temporary login details.
   3. Log in with the following user credentials:

Username: ubuntu
Password: ubuntu

1. 4. Note that there won't be any GUI, so you will need to install lightweight GUIs for ease of use. You can install the LDXE desktop using the following command:

$ sudo apt-get install lxde

2. 5. Remember that if you want to boot from micro SD and not the eMMC, you should make sure that you hold down the boot button and wait for the LED to flash.
3. Installing ROS is pretty straightforward, as we saw in the Installing Armbian and ROS section. Follow the same steps mentioned in that section.

Now, let's learn how set up ROS on Raspberry Pi 3/4.