Quick Start
K4B supports Buildroot (headless) and Ubuntu (login via SSH or UART Serial Terminal). Only the LOGO will be displayed when a monitor is connected.
To start using K4B as a Linux interactive computer , you need to prepare the following items:
- Power Supply
- Display and Display Cable (Optional)
- Boot Media
Power Supply
| Power Mode | Voltage/Current |
|---|---|
| Type - C | 5V/2A(2A is the baseline, or above) |
Type - C
Power supply connection demonstrated:
Display
K4B supports MIPI_LVDS display output.
| Interface | Maximum Resolution Support |
|---|---|
| MIPI | 1920x1200@60Hz |
| LVDS | 1366 x 768@60fps |
The peripheral information of the MIPI_LVDS interface screen is as follows:
| Model | Size | Resolution |
|---|---|---|
| AT101DS40I | 10.1-inch | 800x1280 |
| MX101BA1340 | 10.1-inch | 800x1280 |
| MX080B2140 | 8.0-inch | 800x1280 |
| F050008M01 | 5.0-inch | 720x1280 |
Boot Media
Kickpi K4B is available in two versions: on-board eMMC (embedded Multi Media Card) and NAND. No external boot media is required. However, for subsequent use, if you want to boot from or install an OS via an SD card, you need to prepare an SD card with a storage capacity of ≥ 16GB.
NAND
on-board eMMC
Buttons
K4B has 3 physical buttons on-board, each one has unique function, here are their usage description:
- RST: Short press to hot reset device once.
- USER: Programmable and Customizable Button
- FEL: Located on the bottom side of the board. It is used in the scenario of installing OS Image to on-board eMMC,when pressed and hold with a power-on action, SoC's Init code will put device into MASKROM mode, cooperate with flashing tool to install Image into eMMC / NAND. MASKROM mode means cheating SoC init code into thinking eMMC has nothing programmed, even without U-boot or U-boot is corrupted and unable to work correctly. It give people a chance to reprogram eMMC/NAND after bricking it.
System Startup
User and Password
For any Linux distro Image we released, Default user and password for different distros are as follows:
| System | Username | Password |
|---|---|---|
| Ubuntu20.04 | kickpi | kickpi |
| Ubuntu20.04 | root | root |
| Buildroot | / | / |
Hardware Installation
In below installation diagram, we have installed the power supply, MIPI display, mouse, and keyboard to KickPi K4B (If in you scenario , K4B works as a headless device and without display, here is a way to tell how the device's working and trouble shoot issues via on-board LED).
Note
FPC Antenna has bare metal surface, should avoid direct contact with board. Antenna may also generate electromagnetic interference , harm DDR's signals, please place antenna spatially away from DDR and SoC.
LED Status Indicator
The Linux system equipped on K4B is a headless system. Only the main control model LOGO will be displayed when a monitor is connected. Please judge the system running status via the LED indicators.
- K4B board has two LED indicators. green LED is the power indicator, and blue LED is the heartbeat indicator.
Success
Green LED is steady on, blue LED is blinking.
Failure
If green LED is off when device is powered on, please check power supply or short circuit issue. green LED sucks current directly from DC power without any external control. If the blue LED is off or steady on(no blinking), kernel panic or died. Blinking is controlled by a kernel driver. All our released OS Image work this way: Android, Ubuntu,Debian,Armbian.
Installing Operating System
Obtaining Image
Note
Image Naming Convention: update-t113-s3-kickpi-k4b-buildroot-nand-lvds-7-1024-600-2025102313.img
update: Refers to the complete image package.
t113-s3-kickpi-k4b: Main control model is t113-s3, hardware board type is Kickpi-K4b.
buildroot: File system is Buildroot.
NAND: Storage medium is NAND.
lvds-7-1024-600: 7-inch LVDS display with a resolution of 1024*600.
2025102313.img: Image output date.
Obtain Kickpi K4B image files from OneDrive.
├── 2-Image
│ └── K4B
│ ├── EMMC
│ │ ├── Buildroot201902
│ │ └── Ubuntu2004
│ └── NAND
│ ├── Buildroot201902
│ │ ├── update-t113-s3-kickpi-k4b-buildroot-nand-lvds-7-1024-600-2025102313.img
│ └── Ubuntu2004
SD Card Installation
K4B has a SD card slot ( microSD aka. TransFlash or TF ) which can also serves as a bootable device. In K4B's boot sequence, SD card has higher priority, so K4B always try to boot from SD card first, when no one mounted, K4B then boot from on-board eMMC / NAND. Since SoC vendor's official Tools use terminology SD(microSD) instead of TF, so we use SD card in this context, TF and SD means the same thing.
With SoC vendor's tool, we can make 2 types of booting card. SD Boot Card works like a portable edition OS, e.g. windows PE. We use SD Boot Card to power device for some maintain and fix purpose. also can be used to verify your own customization. the second type is SD installation card. you create this kind of booting card when you try to use it to install new Image into on-board eMMC / NAND. it contains a specific script to create partition, format FS, copy files to eMMC / NAND. Make sure you understand what you need and create the right SD card.
Preparation
Note
Supported SD card filesystem formats: exfat, NTFS
SD Boot Card (SD Boot): Contains bootloader and complete system image, supports device booting directly from microSD card, used in scenarios like eMMC, dev debugging.
SD Installation Card (Upgrade Firmware): Stores firmware image and installation script, used to install or upgrade firmware to the device's on-board storage (e.g., eMMC).
-
Hardware: Windows PC/laptop, USB TYPE-C cable(some cheap TYPE-C cable only provide current, make sure use the one capable of data exchange). some users reported when using double male TYPE-C to TYPE-C cable, installation failed sometimes, when switch to double male USB TYPE-A to TYPE-C, it's ok.
-
Software: Installing tool PhoenixCard, image.
SD Boot Card
Note
The SD Boot Card is classified as an eMMC device. When booting the system from the SD Boot Card on eMMC/NAND motherboards, please select the image from the eMMC folder in the cloud drive for flashing.
1. Navigate to the PhoenixCard extracted folder and launch PhoenixCard.
2. Follow the steps shown in the diagram to flash the downloaded image onto the SD card.
Note
During the operation, if PhoenixCard prompts to format the SD card, confirm the formatting.
The display must be used with the corresponding image. If you have equipped K4B with a 10-inch MIPI/LVDS display, please select the image named update-t113-s3-kickpi-k4b-***-EMMC-mipi-10-800-1280-v2-202*.img.
3. The SD boot card is created successfully.
4. Power off the board, insert the SD Boot Card into the TF card slot of the board, and reconnect the power supply. Since K4B runs a headless system, the startup is successful if the monitor displays the LOGO normally.
Success
The green LED remains lit, and the blue LED blinks continuously (the blue LED will not light up immediately, please wait patiently).
SD Installation Card
Note
When installing the system from an SD card on an eMMC motherboard, select the image from the eMMC folder in the cloud drive for flashing.
When installing the system from an SD card on a NAND motherboard, select the image from the NAND folder in the cloud drive for flashing.
1. Navigate to the PhoenixCard extracted folder and launch PhoenixCard.
2. Follow the steps shown in the diagram to flash the downloaded image onto the SD card.
Note
During the operation, if PhoenixCard prompts to format the SD card, confirm the formatting.
When installing the system from an SD card on an eMMC motherboard, select the image from the eMMC folder in the cloud drive for flashing.
When installing the system from an SD card on a NAND motherboard, select the image from the NAND folder in the cloud drive for flashing.
3. The SD installation card is created successfully.
4. Power off the board, insert the SD Installation Card into the TF card slot of the board, and power on the device again. Wait for the installation to complete. Since K4B runs a headless system, only the LOGO will be displayed on the monitor.
Success
A progress bar will be displayed on the monitor during installation. When the installation is complete, the green LED and blue LED will remain steady on. Power off the board, remove the SD card, power on the board again, and wait for the system to restart.
USB Installation
Preparation
-
Hardware: USB A-to-C cable.
-
Software: Installing tool PhoenixSuit, image.
Steps
1. Connect the computer using a USB A-to-C flashing cable. The board enters the Installation Mode,the green LED stays on.
Note
Installation Mode:
When the motherboard is powered off, press and hold the FEL button on the back of the motherboard, insert the USB flashing cable and connect it to the computer. When the flashing tool detects the device, it is considered to have entered the installation mode, and you can release the FEL button.
When the motherboard is powered on, insert the USB flashing cable, press and hold the FEL button on the back of the motherboard, then press the RST button briefly. When the flashing tool detects the device, it is considered to have entered the installation mode, and you can release the FEL button.
2. Install driver, connect the computer via a USB A - to - C cable, open the computer's Device Manager, and follow the operations shown in the diagram.
Tip
Driver folder path: PhoenixSuit/Drivers/AW_Driver/
3. Open PhoenixSuit from the extracted folder in Administrator mode.
4. In the installing software, click "firmware" to select the image to be install (do not click "Upgrade").
Note
For the K4B eMMC version, please select the image from the eMMC folder in the cloud drive for flashing.
For the K4B NAND version, please select the image from the NAND folder in the cloud drive for flashing.
5. Re-enter the installing mode on the development board, connect the USB, and when the software displays the screen as shown below, click "Yes" to start installing. Simply wait for the installing to complete successfully.
Note
Installation Mode:
When the motherboard is powered off, press and hold the FEL button on the back of the motherboard, then insert the USB flashing cable to connect to the computer. Once the flashing tool detects the device (indicating entry into installation mode), release the FEL button.
When the motherboard is powered on, insert the USB flashing cable, press and hold the FEL button on the back of the motherboard, then press the RST button briefly. Once the flashing tool detects the device (indicating entry into installation mode), release the FEL button.
6. Once the image is installed successfully, the board will restart automatically.
Success
The green LED is steady on, and the blue LED is flashing continuously. (Note: The blue LED will not light up immediately; please wait patiently.)
System Configuration
In this chapter, you will use Mobaxterm for serial debugging, ADB for Android debugging, and SSH for remote connection.
Account and Password
Default usernames and passwords for different systems are as follows:
| System | Username | Password |
|---|---|---|
| Ubuntu20.04 | kickpi | kickpi |
| Ubuntu20.04 | root | root |
| Buildroot | / | / |
Mobaxterm
Using Serial Port debugging tool connect K4B to get a console. please check pinout to find UART pins as shown in below diagram.
K4B DEBUG UART Pins
- Physical Image
Tool Preparation
- Software: Mobaxterm
- Hardware: Serial Debug Cable aka. USB-TTL debug cable
Note
Red: VCC (no need to connect); Green: TX; White: RX; Black: GND. If you can't get Serial Port output in Mobaxterm, just switch Green and White wire and try again.
Hardware Installation
- Diagram
Mobaxterm Configuration
1. Click session to create a new session window.
2. Select the session window type as serial.
3. Select the serial COM port number (Check COM number by opening Windows Device Manager -> Ports interface).
4. Set Speed(bps) to 115200.
5. Start the session window.
As shown, after clicking OK, you will enter the command-line input window.
When the board is powered on and connected to the computer, Mobaxterm will display the information output of the development board during startup.
Connection successful. Press Enter in the command-line interface to input commands, successfully logging into the mainboard console.
ADB
Android system supports ADB functionality. ADB (Android Debug Bridge) is an Android system debugging bridge tool. It supports connecting to devices via USB or network, enabling device management and debugging operations such as app installation, file transfer, command execution, etc. ABD is a utility inside Google's Android platform-tools. you can download platform-tools from Google's developer site also.
Tool Preparation
- Hardware: USB Type-C Data Cable
- Software: download ADB_Tool
Hardware Installation
Connect one end of the USB TYPE-C data cable to the mainboard, the other end to the personal host.
ADB Installation
1. Extract the compressed package, e.g., to Windows path D:\ADB\adb-tools.
2. Open cmd window, switch to the extraction directory.
3. Run the command. Successful run indicates installation success.
4. Start ADB debugging.
SSH
SSH stands for Secure Shell, an encrypted network transmission protocol. Its core function is to securely remotely log into servers, execute commands, or transfer files in insecure network environments.
Account and Password
Default usernames and passwords for different systems are as follows:
| System | Username | Password |
|---|---|---|
| Ubuntu2204 | kickpi | kickpi |
| Ubuntu2204 | root | root |
| Buildroot | / | / |
IP Address Acquisition
DHCP automatically assigns IP addresses; no settings are needed. Device IP can be obtained in multiple ways.
- via serial port: Enter
ifconfig eth0in the serial terminal to get IP address (Serial connection refer to Mobaxterm chapter above).
SSH Connection
Enter the command in the command line to perform SSH connection:
Example:
PS C:\Users\16708> ssh kickpi@192.168.77.186
The authenticity of host '192.168.77.186 (192.168.77.186)' can't be established.
ED25519 key fingerprint is SHA256:635IZrLQdeYlWWl3SCdLxu9fxLEPmStBapj4APCjzZE.
This key is not known by any other names.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Warning: Permanently added '192.168.77.186' (ED25519) to the list of known hosts.
kickpi@192.168.77.186's password:
Welcome to Ubuntu 24.04.2 LTS (GNU/Linux 6.1.75 aarch64)
* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/pro
This system has been minimized by removing packages and content that are
not required on a system that users do not log into.
To restore this content, you can run the 'unminimize' command.
To run a command as administrator (user "root"), use "sudo <command>".
See "man sudo_root" for details.
kickpi@kickpi:~$
Q&A
- ROOT User Login Failed ?
1. Check if configuration was successful
Run the following commands. If the output is PermitRootLogin yes, it indicates configuration success:
console$ cat /etc/ssh/ssh_config | grep PermitRootLogin
PermitRootLogin yes
console$ cat /etc/ssh/sshd_config | grep PermitRootLogin
PermitRootLogin yes
2. Root user login configuration
Modify SSH configuration files: