1. Get Started

1.1 Introduction

RUBIK Pi 3 is developed based on the Qualcomm QCS6490 processor which features the Qualcomm® Kryo™ 670 CPU and the Qualcomm® Hexagon™ Processor with fused AI-accelerator architecture. The processor provides exceptional AI performance of 12.5 TOPS and offers the capability for various machine learning and AI application scenarios.

RUBIK Pi 3 is designed with a wide range of interfaces and functions, such as USB, camera, DisplayPort, HDMI, Ethernet, a 3.5mm headphone jack, Wi-Fi, Bluetooth, M.2 connector, fan, RTC, and a 40-pin LS connector. These features cater to diverse development needs while facilitating rapid development and efficient debugging. RUBIK Pi 3 is compatible with various systems, such as Qualcomm Linux, Canonical Ubuntu for Qualcomm Platforms*, and Android 13, providing developers with the flexibility to meet their specific application needs.

*Canonical Ubuntu for Qualcomm Platforms is in the planning phase

1.2 Specifications

Category	RUBIK Pi 3 Feature
SoC	QCS6490
Processor	1 x Cortex-A78 2.7 GHz 3 x Cortex-A78 2.4 GHz 4 x Cortex-A55 1.9 GHz
GPU	Adreno 643 GPU @ 812 MHz
VPU	Adreno 633 VPU
NPU	12.5 TOPS
ISP	Spectra ISP capable of terminal-side machine learning and machine processing
RAM	8 GB LPDDR4x
ROM	128 GB UFS 2.2
Wi-Fi & Bluetooth	Wi-Fi 5 and Bluetooth 5.2
Camera	2 x 4-lane MIPI CSI D-PHY connector
USB	1 x USB Type-C (USB3.1 Gen1) 2 x USB3.0 1 x USB2.0
GPIOs	28 GPIO pins
Ethernet	1000M
M.2 connector	M.2 Key M 2280 (PCIe3.0 2-lane)
Audio	3.5mm headphone jack

1.3 Preparations

Computer running Windows 10 and later, or Ubuntu 18 and later
RUBIK Pi 3
USB Type-A to Type-C cable
USB Type-A to Micro USB cable
Power supply (12V 3A Type-C)

1.3.1 Install drivers

1.3.1.1 Install drivers in a Windows environment

1.3.1.1.1 Install QUD

Click https://github.com/rubikpi-ai/tools/blob/main/qud/qud.win.1.1_installer_10061.1.zip to download the installation package.

Decompress qud.win.1.1_installer_10061.1.zip, run setup.exe as shown in the following figure, and click Next.

Click Next.

Select the I accept the terms in the license agreement option and click Next.

Click Install.

Click Finish to complete the driver installation.

1.3.1.1.2 Install Tflash

Click https://github.com/rubikpi-ai/tools/blob/main/tflash/windows/TflashSetup_v1.2.0.4.exe to download the installation package.

Run TflashSetup_v1.2.0.4.exe. Select the desired language and click OK.

Select the location where you want to install Tflash and click Next.

Click Next.

Select the Create a desktop shortcut option and click Next.

Click Install.

Select the Launch Tflash option and click Finish.

If the following error message appears, click Yes. Follow the instructions to download the required installation package.

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Double-click the package you downloaded and click Install.

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Click Close to complete the installation.

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After the installation is completed, the following Tflash icon will appear on your desktop and in the Start menu.

1.3.1.2 Install drivers in an Ubuntu environment

1.3.1.2.1 Install Tflash

Click https://github.com/rubikpi-ai/tools/blob/main/tflash/ubuntu/Thundercomm-tflash-v1.0.0.deb to download the installation package.

Run the following command to install Tflash.

   sudo dpkg -i Thundercomm-tflash-v1.0.0.deb

After the installation is completed, run the tflash command in the terminal. If the following message appears, it indicates that Tflash has been successfully installed:

1.3.2 Download images

RUBIK Pi 3 comes with a pre-installed Linux image for a quick out-of-the-box experience. If you need the latest version of the Linux image or other operating system images, please visit the official website https://www.thundercomm.com/product/rubik-pi/ to download.

Visit GitHub to download the Linux source code at https://github.com/rubikpi-ai as needed.

Qualcomm Linux is a simplified desktop system based on Weston. It is suitable for developers who have Linux development experience and seek an in-depth development experience.

Canonical Ubuntu for Qualcomm Platforms (under development) is a comprehensive system built on Ubuntu 24. The system provides more desktop applications, a better user experience, and a wealth of development resources. It is suitable for developers seeking an efficient development environment.
Android 13 is an enhanced system based on Google AOSP, offering an improved experience for developers working on Android applications.

1.3.3 Flash images

Before flashing images, enter the flash mode (9008 mode) using one of the following methods:

Method 1
Method 2
Method 3

Connect the power supply into port 10.
Press and hold the [EDL] button (No. 12).

Insert the Type-C cable into port 5 and wait for three seconds to enter 9008 mode.

Insert the power supply into port 10.

Insert the Type-C cable into port 5.

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After RUBIK Pi 3 boots up, run the following command to enter 9008 mode.

    adb shell reboot edl

1.3.3.1 Flash images on a Windows system

Open the Tflash software. Make sure the device is in 9008 mode, as shown in the following figure:

Select the Storage Type of the device to be flashed. For RUBIK Pi 3, select UFS for Storage Type.

Select Reset After Download or Erase All Before Download as needed. Exercise caution when selecting Erase All Before Download.

Reset After Download: When this option is selected, the device will reboot automatically after image flashing is completed.
Erase All Before Download: When this option is selected, the data in each RUBIK Pi UFS partition will be erased before flashing.

warning

The Erase All Before Download option takes effect only when the UFS partitions are the same before and after flashing.
Selecting Reset After Download or Erase All Before Download is not a mandatory action. You are not required to select one of them.

Flash the FlatBuild image.

a. Click Browse.

b. Go to the FlatBuild directory, select Programmer File, and select prog_firehose_ddr.elf.

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c. Select all .xml files whose names start with "rawprogram".

$C:\Users\thundersoft\AppData\Roaming\LarkShell\OptimizeImage\072d944a-f199-4a33-8298-3855ec39b5d5.jpeg$

d. Select all .xml files whose names start with "patch".

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After the above settings, the related information will be displayed in the Tflash interface.

e. Click Download to start flashing.

tip

The flashing time varies from computer to computer. The green progress bar shows the flashing progress.

After images are successfully flashed, the following logs will be displayed:

If you have selected Reset After Download, the board will reboot automatically after flashing.
If you have not selected Reset After Download, disconnect the power cable and USB cable to power off RUBIK Pi 3, then reconnect the power cable and press the [PWR ON] button to start RUBIK Pi 3.

1.3.3.2 Flash images on an Ubuntu system

Go to the FlatBuild package directory.
Run tflash -r.

tip
Run the tflash -h command to view more parameters. -r in the above command indicates restarting your RUBIK Pi 3 after flashing is completed.
When "Stop the ModemManager on your host PC and press Enter on your keyboard to continue..." appears on the screen, press Enter to flash images.

If the following information is displayed after the tflash operation, it indicates that flashing was successful.

tip

When running tflash on your PC, enter the sudo password as prompted. The password is the login password for the PC.

After successful image flashing by using the -r parameter, RUBIK Pi 3 automatically reboots.

1.4 Power-on

Connect the power supply and press the [PWR ON] button to power on RUBIK Pi 3.

$C:\Users\thundersoft\AppData\Roaming\LarkShell\OptimizeImage\3eea2a16-6fb3-49f7-9972-353c93f87041.jpeg$

1.5 Power-off

Run the poweroff command to power off RUBIK Pi 3.

1.6 Reboot

Run the reboot command.

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Press and hold the [PWR ON] button for 12 seconds to reboot RUBIK Pi 3.

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1.7.1 Windows

Connect port 2 in the following figure to a computer via a serial cable.

Open the computer settings page, check the corresponding COM port in Device Manager, and record the port.

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Download MobaXterm at https://mobaxterm.mobatek.net/ and decompress to use it.

$C:\Users\thundersoft\AppData\Roaming\LarkShell\OptimizeImage\8403a2df-3320-4ea1-98e9-aecb5e156051.jpeg$

Open MobaXterm, select Session > Serial, and set the baud rate of the serial port to 115200.

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Click OK. Press Enter and type your login name and the default login password to log in:

Qualcomm Linux

Login account: root
Login password: rubikpi

tip

You can run the passwd command to change the default password. For example:

    passwd root

1.7.2 Ubuntu

Connect port 2 in the following figure to a computer via a serial cable.

Run the following commands to install minicom:

    sudo apt update  
    sudo apt install minicom

Run the following command to check the USB port:

    ls /dev/ttyACM*

Run the following command to open minicom. Press Enter and type your login name and the default login password to log in:

    sudo minicom -D /dev/ttyACM0 -b 115200

Qualcomm Linux

Login account: root
Login password: rubikpi

tip

You can run the passwd command to change the default password. For example:

    passwd root

1.8.1 Windows

1.8.1.1 Preparations

1.Download the ADB and Fastboot installation package at https://developer.android.google.cn/tools/releases/platform-tools and decompress the package.

2.Right-click This PC and choose Properties. Click Advanced and click Environment Variables. Alternatively, right-click This PC and choose Properties. In the search bar, type Advanced system settings and click Environment Variables.

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3.Under System variables, select Path and click Edit.

$C:\Users\thundersoft\AppData\Roaming\LarkShell\OptimizeImage\352d435f-6706-4f90-9d12-ef02f28ac33c.jpeg$

4.Click New and type the path of decompressed platform-tools in Step 1. Click OK to save the environment variable.

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Press Win+R and type "CMD" to open the Windows terminal. Run the following commands to log in to your RUBIK Pi 3:

adb devices # Check if devices are connected  
adb root    # Log in as root user  
adb shell   # Open the adb terminal

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1.8.2 Ubuntu

1.8.2.1 Preparations

1.Run the following command to install the ADB and Fastboot tools:

sudo apt install git android-tools-adb android-tools-fastboot wget

2.Update the udev rules file.

a.Run the following command to open and modify the 51-qcom-usb.rules file.

    sudo vi /etc/udev/rules.d/51-qcom-usb.rules

b.Add the following content to the file. If the following content already exists, skip this step.

    SUBSYSTEMS=="usb", ATTRS{idVendor}=="05c6", ATTRS{idProduct}=="9008", MODE="0666", GROUP="plugdev"

c.Run the following command to restart udev.

    sudo systemctl restart udev

note

If RUBIK Pi 3 is already connected to the PC via USB, plug and unplug the USB cable to reconnect RUBIK Pi 3 so that the updated rules take effect.

Run the following commands in the terminal to log in to your RUBIK Pi 3:

adb devices # Check if devices are connected  
adb root    # Log in as root user  
adb shell   # Open the adb terminal

1.9.1 Windows

Confirm the network connection.

a. To use SSH login, ensure the RUBIK Pi 3 is connected to the network and the host can successfully ping it. Run the following command to obtain the IP address of RUBIK Pi 3:
```
ifconfig
```
b. Press Win+R, type "cmd" in the pop-up window, and click OK.

c. Run the following command in the terminal and view the execution result.
```
ping 10.9.5.59
```

SSH login

a. Open MobaXterm.

$C:\Users\thundersoft\AppData\Roaming\LarkShell\OptimizeImage\7a8190d1-0383-411f-9d93-0ef96bbde2d3.jpeg$

b. Click Session and select SSH in the pop-up window.

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c. Type the IP address of the RUBIK Pi 3 you want to log in to and click OK.

$C:\Users\thundersoft\AppData\Roaming\LarkShell\OptimizeImage\12fe8bd5-ee01-4a51-b1b2-273fa41bc441.jpeg$

d. Type the username, press Enter, type the password, and press Enter to log in to RUBIK Pi 3.

$C:\Users\thundersoft\AppData\Roaming\LarkShell\OptimizeImage\1982f612-258a-4389-b586-2221bad9bad4.jpeg$

e. The following information indicates that the login is successful.

$C:\Users\thundersoft\AppData\Roaming\LarkShell\OptimizeImage\25587927-f85b-47a4-a93c-7ddc06e640cc.jpeg$

1.9.2 Ubuntu

Confirm the network connection.

a. To use SSH login, ensure the RUBIK Pi 3 is connected to the network and the host can successfully ping it. Run the following command to obtain the IP address of RUBIK Pi 3:
```
ifconfig
```
$C:\Users\thundersoft\AppData\Roaming\LarkShell\OptimizeImage\222c5f91-c44c-45c1-a7e8-e2e4b453aec2.jpeg$

b. Run the following command in the Ubuntu terminal and view the execution result.
```
ping 10.9.5.59
```
$C:\Users\thundersoft\AppData\Roaming\LarkShell\OptimizeImage\7d0e73ce-06de-4b28-97d5-7f6fd3ab5f1c.jpeg$
SSH login

a. Type the following command in the Ubuntu terminal and press Enter. root indicates the role you want to log in as. 10.9.5.59 indicates the IP address of RUBIK Pi 3.
```
ssh root@10.9.5.59
```
b. Type the password and press Enter. The login succeeds.

$C:\Users\thundersoft\AppData\Roaming\LarkShell\OptimizeImage\daea85e9-bad1-4d27-a364-28e683f7a3b8.jpeg$

1.10 File transfer

1.10.1 ADB

In the PC terminal, run the following command to upload the test.txt file to the /opt directory:

    adb push test.txt /opt

In the PC terminal, run the following command to download the test.txt file to your current directory:

    adb pull /opt/test.txt ./

1.10.2 SCP

To use Secure Copy Protocol (SCP) transfer, ensure the RUBIK Pi 3 is connected to the network. For example, if the IP address of RUBIK Pi 3 is 10.9.5.59, run the following commands:

tip

Run the ifconfig command on RUBIK Pi 3 to obtain its IP address.

In the PC terminal, run the following command to upload the test.txt file to the /opt directory:

    scp test.txt root@10.9.5.59:/opt

In the PC terminal, run the following command to download the test.txt file to your current directory:

    scp root@10.9.5.59:/opt/test.txt ./

1.11 Set up the Ubuntu development environment

1.11.1 Install software

Run the following commands in the Ubuntu terminal to install the following software.

   sudo apt update
   sudo apt install repo gawk wget git diffstat unzip texinfo gcc build-essential chrpath socat cpio python3 python3-pip python3-pexpect xz-utils debianutils iputils-ping python3-git python3-jinja2 libegl1-mesa libsdl1.2-dev pylint xterm python3-subunit mesa-common-dev zstd liblz4-tool locales tar python-is-python3 file libxml-opml-simplegen-perl vim whiptail bc
   sudo apt-get install lib32stdc++6 libncurses5 checkinstall libreadline-dev libncursesw5-dev libssl-dev libsqlite3-dev tk-dev libgdbm-dev libc6-dev libbz2-dev libffi-dev curl git-lfs

Run the following commands in the Ubuntu terminal to install Python 3.10.2. In the Linux kernel packaging process, the python3.10 command is used. If you have installed Python 3.10.2 or later, skip this step.

    python --version
    # Download it in a directory of your choice
    wget https://www.python.org/ftp/python/3.10.2/Python-3.10.2.tgz
    tar -xvf Python-3.10.2.tgz
    cd Python-3.10.2
    ./configure --enable-optimizations
    make
    sudo make install

Run the following command in the Ubuntu terminal to install pefile.

   sudo pip3.10 install pefile

1.11.2 Install cross-compilation tools

Run the following commands in the Ubuntu terminal to download the cross-compilation toolchain for RUBIK Pi 3.

    git clone https://github.com/rubikpi-ai/toolchains.git
    git lfs pull

Run the following commands in the Ubuntu terminal to install the cross-compilation toolchain.

    cd toolchains
    ./qcom-wayland-x86_64-meta-toolchain-armv8-2a-qcm6490-toolchain-1.0.sh

Follow the prompts to install the cross-compilation environment, type the absolute path to the installation directory, and type "Y".
After the installation is completed, go to the installation directory and run the following command to set up the cross-compilation environment

   source environment-setup-armv8-2a-qcom-linux

Run the following command in the Ubuntu terminal to check the version of the gcc toolchain. If the output is as follows, it indicates that the cross-compilation environment is set up successfully.

   aarch64-qcom-linux-gcc -v

1.11.3 Use the cross-compilation tools

After setting up the cross-compilation environment by using the source environment-setup-armv8-2a-qcom-linux command as described in the previous section, use the following method to cross-compile the executable program of RUBIK Pi 3.

1.11.3.1 Use the Makefile build

The header file path sysroot must be set for cross-compilation. Use the --sysroot=dir parameter to specify the path.

aarch64-qcom-linux-gcc --sysroot=/home/zhy/rubikpi/sdk/sysroots/armv8-2a-qcom-linux

warning

In the above command, the cross-compilation toolchain is placed at the /home/zhy/rubikpi/sdk directory of the PC. Change the directory to your actual directory.

1.11.3.2 Build the project using CMake

The following is an example using aarch64.cmake:

set(CMAKE_SYSTEM_NAME Linux)
set(CMAKE_SYSTEM_PROCESSOR arm64) #Set the target processor architecture

#Set sysroot
set(TOOLCHAIN_DIR /home/zhy/rubikpi/sdk/sysroots/armv8-2a-qcom-linux)
set(CMAKE_SYSROOT ${TOOLCHAIN_DIR}/sysroots/armv8-2a-qcom-linux)

#Set the cross-compiler
SET(CMAKE_C_COMPILER ${TOOLCHAIN_DIR}/sysroots/x86_64-qcomsdk-linux/usr/bin/aarch64-qcom-linux/aarch64-qcom-linux-gcc)
SET(CMAKE_CXX_COMPILER ${TOOLCHAIN_DIR}/sysroots/x86_64-qcomsdk-linux/usr/bin/aarch64-qcom-linux/aarch64-qcom-linux-g++)
set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)

When using CMake to build a project, create a CMakeLists.txt according to the actual situation of the project and run the following command to generate the Makefile.

cmake -DCMAKE_TOOLCHAIN_FILE=aarch64.cmake

1.12 Linux kernel

It is advisable to conduct Linux kernel development in an environment running Ubuntu 18 or a later version.

1.12.1 Download code

Run the following command to download code:

git clone https://github.com/rubikpi-ai/linux.git

1.12.2 Compile code

Set up the cross-compilation environment. For details, refer to "1.11.2. Install cross-compilation tools".

    source <your toolchains directory>/environment-setup-armv8-2a-qcom-linux

warning

The cross-compilation environment is only effective in the current terminal.

If the following error occurs, input the unset LD_LIBRARY_PATH command as prompted and run the above command again.

Go to the kernel directory and compile the kernel.

   ./rubikpi_build.sh -a

note

The first compilation takes a longer time based on different computer configurations. In most cases, it takes less than 20 minutes. Subsequent compilations are only performed on modified code.
The kernel directory can be cleaned up using the make clean command, after which all compilation artifacts and some configuration content will be deleted.

Go to the kernel directory. Package the kernel and device tree image.

    ./rubikpi_build.sh -dp -ip # Package image

warning

If the following error occurs when you package the image:

$C:\Users\thundersoft\AppData\Roaming\LarkShell\OptimizeImage\d3d1c31b-7088-492a-8fb1-1d1766c3013c.jpeg$

Run the following command to modify the .mtoolsrc file, add mtools_skip_check=1, and try packaging the image again.

vim ~/.mtoolsrc

Go to the kernel directory and flash the kernel and device tree image.

    ./rubikpi_flash.sh -d -i -r # Flash

warning

Before flashing, ensure that RUBIK Pi 3 has entered fastboot mode. Use one of the following methods to enter fastboot mode:

In the RUBIK Pi 3 terminal, input reboot bootloader. When RUBIK Pi 3 enters fastboot mode, the blue indicator lights up.
Press and hold the [PWR ON] button until the blue indicator lights up.

For details about how to use the ./rubikpi_build.sh and ./rubikpi_flash.sh scripts, use the –h parameter.

Compile the ko driver module separately.

a. Create a Makefile as follows. Change KDIR to the actual kernel source code directory.

obj-m += hello.o  
KDIR:=/home/rubikpi/kernel-6.6  
PWD?=$(shell pwd)  
all:   
 make -C $(KDIR) M=$(PWD) modules  
 echo $(PWD)  
clean:   
 rm -f *.ko *.o *.mod *.mod.o *.mod.c *.symvers *.order

b. Create a hello.c file as follows:

#include <linux/module.h>  
#include <linux/init.h>  
  
static int hello_init(void)  
{  
 printk("hello RUBIK Pi!\n");  
 return 0;  
}  
  
static void hello_exit(void)  
{  
 printk("bye RUBIK Pi!\n");  
}  
  
module_init(hello_init);  
module_exit(hello_exit);  
  
MODULE_LICENSE("GPL");  
MODULE_VERSION("V1.0");  
MODULE_AUTHOR("RUBIK Pi");

c. Run the following commands to compile the ko driver module:

export ARCH=arm64  
export CROSS_COMPILE=aarch64-qcom-linux-  
make

d. Transfer hello.ko to your RUBIK Pi 3 using the ADB or SCP method.

e. Run the following commands on your RUBIK Pi 3 to verify that the compilation artifact is valid.

insmod hello.ko
rmmod hello.ko
dmesg | grep "RUBIK Pi"

1.12.3 Configure the kernel

Run the following commands to configure the Linux kernel using menuconfig:

cd kernel-6.6/  
make ARCH=arm64 menuconfig

After the configuration is completed, run the following commands to save the configuration.

make ARCH=arm64 savedefconfig  
cp defconfig ./arch/arm64/configs/rubik_pi3_defconfig

1.12.4 Directory analysis

After the operations in 1.12.1. Download code and running the git clone command, the RUBIK Pi 3 Linux repository is as shown in the following figure:

The major folders and files are described as follows:

Name	Description
arch	Architecture-related directory
block	Block device-related directory
certs	Certification and signature-related directory
crypto	Encryption-related directory
documentation	Documentation-related directory
drivers	Driver-related directory
firmeare	Firmware-related directory
fs	File system-related directory
include	Header file-related directory
init	Kernel initialization-related directory
ipc	Inter-process communication-related directory
kernel	Directory of the kernel core code
lib	Directory of kernel core library code
mm	Directory of memory management-related code
net	Directory of network protocol-related code
samples	Directory of kernel compilation examples
scripts	Directory of kernel compilation and configuration scripts
security	Security architecture-related directory
sound	Audio system-related directory
tools	Directory of kernel interaction tools
usr	initramfs-related directory, used to generate the initramfs
virt	Directory that provides Kernel-based Virtual Machine (KVM) technologies
rust	Rust-related directory
rubikpi	RUBIK Pi 3 related directory for storing compilation tools
techpack	Qualcomm platform-related driver
.config	Configuration file for final kernel compilation
Makefile	Main file used to compile the kernel
Kbuild	Script for configuring kernel settings
Kconfig	Configuration file for the graphical configuration interface
MAINTAINERS	List of maintainers
CREDITS	Linux contributors
COPYING	Copyright statement
rubikpi_build.sh	Compilation and packaging scripts provided by RUBIK Pi 3
rubikpi_flash.sh	Flash scripts provided by RUBIK Pi 3

1.12.4.1 Device tree

The top-level device tree of RUBIK Pi 3 is rubikpi3-c6490.dts which is located at the arch/arm64/boot/dts/qcom directory. It is recommended that all modifications to the device tree be made on this file.

In addition, during the development process, the sc7280.dtsi in the same level of directory may be frequently viewed. sc7280.dtsi has nodes commonly used during the development process, including GPIO, SPI, I2C, UART, CPU, and GPU.

1.1 Introduction​

1.2 Specifications​

1.3 Preparations​

1.3.1 Install drivers​

1.3.1.1 Install drivers in a Windows environment​

1.3.1.1.1 Install QUD​

1.3.1.1.2 Install Tflash​

1.3.1.2 Install drivers in an Ubuntu environment​

1.3.1.2.1 Install Tflash​

1.3.2 Download images​

1.3.3 Flash images​

1.3.3.1 Flash images on a Windows system​

1.3.3.2 Flash images on an Ubuntu system​

1.4 Power-on​

1.5 Power-off​

1.6 Reboot​

1.7 Serial port login​

1.7.1 Windows​

1.7.2 Ubuntu​

1.8 ADB login​

1.8.1 Windows​

1.8.1.1 Preparations​

1.8.1.2 ADB login​

1.8.2 Ubuntu​

1.8.2.1 Preparations​

1.8.2.2 ADB login​

1.9 SSH login​

1.9.1 Windows​

1.9.2 Ubuntu​

1.10 File transfer​

1.10.1 ADB​

1.10.2 SCP​

1.11 Set up the Ubuntu development environment​

1.11.1 Install software​

1.11.2 Install cross-compilation tools​

1.11.3 Use the cross-compilation tools​

1.11.3.1 Use the Makefile build​

1.11.3.2 Build the project using CMake​

1.12 Linux kernel​

1.12.1 Download code​

1.12.2 Compile code​

1.12.3 Configure the kernel​

1.12.4 Directory analysis​

1.12.4.1 Device tree​

1.1 Introduction

1.2 Specifications

1.3 Preparations

1.3.1 Install drivers

1.3.1.1 Install drivers in a Windows environment

1.3.1.1.1 Install QUD

1.3.1.1.2 Install Tflash

1.3.1.2 Install drivers in an Ubuntu environment

1.3.1.2.1 Install Tflash

1.3.2 Download images

1.3.3 Flash images

1.3.3.1 Flash images on a Windows system

1.3.3.2 Flash images on an Ubuntu system

1.4 Power-on

1.5 Power-off

1.6 Reboot

1.7 Serial port login

1.7.1 Windows

1.7.2 Ubuntu

1.8 ADB login

1.8.1 Windows

1.8.1.1 Preparations

1.8.1.2 ADB login

1.8.2 Ubuntu

1.8.2.1 Preparations

1.8.2.2 ADB login

1.9 SSH login

1.9.1 Windows

1.9.2 Ubuntu

1.10 File transfer

1.10.1 ADB

1.10.2 SCP

1.11 Set up the Ubuntu development environment

1.11.1 Install software

1.11.2 Install cross-compilation tools

1.11.3 Use the cross-compilation tools

1.11.3.1 Use the Makefile build

1.11.3.2 Build the project using CMake

1.12 Linux kernel

1.12.1 Download code

1.12.2 Compile code

1.12.3 Configure the kernel

1.12.4 Directory analysis

1.12.4.1 Device tree