Bootloader Installation: RPi-Flex

Installing the KOS bootloader installs the node manager, the necessary software to recognize the board as a KOS device. KOS Studio recognizes KOS Devices and can interact with them as needed.

Node discovery lists all the possible devices running KOS in your network and all devices connected via KOS Studio within your organization.

Prerequisites

Software:

  • Ensure your Mac or Windows machine has the Raspberry Pi Imager installed. If needed, you can install it from here.
  • Ensure you have RPi USB boot software. If needed, you can install it from here.

Hardware:

  • A Windows or Mac machine with a USB Standard-A port (or the with supported USB hub or adapter).
  • A Raspberry Pi Flex connected to a CM4 IO board.
  • An HDMI monitor, keyboard, and ethernet cable that you’ll connect to the Flex board.
  • One USB cable, Type-A male to Micro-B male (Amazon).
  • One jumper cap (Amazon).

Step 1: USB boot RPi Flex

  • With the power cord connected to the RPi IO board, discharge any static electricity buildup from your body by touching a grounding point, such as the metal body surrounding the ethernet socket on the RPi board.
  • Remove power from the RPi board.
  • Install a jumper on the J2 connector across the pins labeled Fit jumper to disable eMMC Boot.
  • Plug a USB cable directly (don’t use a hub) from your computer into the USB Slave micro-USB port on the IO Board.
  • Plug the power back into the RPi board. The red D1 LED turns on when it powers on, but the module won’t boot.
  • Run rpiboot from usbboot to mount RPi as a USB drive on your machine.
cd usbboot
sudo ./rpiboot

  • You should have a boot drive on your laptop or MacBook when this exits.

Step 2: Download the bootloader for RPi-Flex

  • Download the Rpi-Flex bootloader.
    • If you use Safari to download the file, the file is automatically unarchived, and the *.img file will be in the download location.
    • On other browsers, unarchive the *.img.gz file for flashing.

Step 3: Install bootloader on board

  • Start the RPi Imager installed on the machine.
  • Locate and select the ‘.img’ and select the drive representing the RPi in boot mode.
  • Follow the instructions for RPi Imager to flash the image to the flash drive.

Step 4: Verification

  • Turn off the power to the board
  • Remove the RPI from the CM4 IO board and plug it into the Flex board setup.
  • Power up the Flex board and wait for a few seconds to boot up.
  • The screen should show “Node Manager,” and the IP should be displayed.
  • You can use this IP in KOS Studio to interact with the device such as installing your device images.