This is the setup recommended for developers using the Raspberry Pi 4 (RPi4) device directly. See Raspberry Pi 4 Setup in LAVA for setting up devices for use in LAVA.

Required items

You should have at least:

  • 1 Raspberry Pi 4 B device
  • 1 Power adaptor
  • 1 USB to serial cable/converter (3.3v is mandatory)
  • 1 MicroSD card

RPi4 board setup

Attach serial

Please ensure you are using the USB to serial which is 3.3v!

  1. Ensure the RPi4 device is off and USB to serial cable is not attached to USB

  2. Connect serial to UART ports on RPi4 device.

    RPi serial

    Attach cable wires to pins 6(GND), 8(TXD) and 10(RXD). Keep in mind that RXD from USB serial should be connected to pin 8(TXD) on RPi4 and TXD from USB to pin 10(RXD).

  3. Connect USB serial to host.

  4. Connect terminal emulator on your host.

    Depending on USB serial and operational system you are using the name of UART may differ, as well as the terminal emulator. The parameters for your terminal emulator should be 115200/8-N-1.

    For Linux-based systems it is usually ttyUSB0 and you may use minicom or screen to connect to serial:

    minicom -b 115200 -o -D /dev/ttyUSB0


    screen /dev/ttyUSB0 115200

Update bootrom with RPi Imager

It is highly recommended to upgrade the bootrom to the latest available stable version!

The easiest method for updating and managing the boot sequence for local usage and development is the RPI Imager which will prepare the bootable SD-card with fresh updates for you:

Misc utility images

Select boot mode

Insert the prepared SD-card into RPi4 and power on the device, on serial you will see the output similar to:

SIG vl805.sig 6246230ecd5b472902e6a49c95e857a5e3190c4fa6c462d6a8867e9a5e523a7c 0
Read vl805.bin bytes    99224 hnd 0x0000009f
PCI reset
PCI reset
VL805 EEPROM is up to date
SIG pieeprom.sig 54285fd35a75f93f59e59bb04706b6a74faaeba91fad5a2cd5bb2279a8a439ab 0
Read pieeprom.bin bytes   524288 hnd 0x00000004
Reading EEPROM: 524288
Bootloader EEPROM is up to date

If you have a display attached to device, it will have a green color in case of success.

Apertis OS startup

The technology preview of RPi4 support has been added into Apertis in v2021 release. However it is recommended to use version v2022dev3 or newer to get the most supported image.

The support for RPI Imager is ongoing.

  1. On your host download the fixedfunction image for Raspberry Pi 4 arm64 architecture and corresponding bmap file (both must have _rpi64_ suffix in file names). For instance, for apertis_v2022dev3-fixedfunction-arm64-rpi64_20210630.0018.img.gz:

  2. Flash the downloaded images onto SD-card with bmaptool, assuming the /dev/mmcblk0 is your card reader device:

    sudo bmaptool copy apertis_v2022dev3-fixedfunction-arm64-rpi64_20210630.0018.img.gz /dev/mmcblk0

    Ensure that the target device is not your hard disk to avoid damaging your data!

  3. Insert the prepared SD-card into RPi4 device and power on the board. In a few seconds you will see on serial the U-Boot is starting:

    U-Boot 2021.01+dfsg-3apertis2bv2022dev3b1 (Jun 22 2021 - 20:50:32 +0000)
    DRAM:  1.9 GiB
    RPI 4 Model B (0xb03111)
  4. The Apertis will ask the login prompt:

    Apertis v2022dev3 apertis ttyS1
    apertis login:

    You can login to the console with the username user and password user.