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OOWOW User Manual

Short introduction: OOWOW getting started

Main Features

  • Install / reinstall OS
  • Download online OS images
  • Backup and restore system
  • Display full device information
  • Configure device
  • Device hardware testing
  • Online script collection
  • Rescue shell
  • Developer and advanced features


Supported devices: OOWOW Devices

Hardware Buttons

You can use the three hardware-buttons on your device to interact directly with the oowow system, we will describe them in more detail within the next section.

  • RESET - reset device
  • FUNCTION - multi functions
  • POWER - multi functions

Common Button Shortcuts

  • Boot OOWOW - hold FUNCTION and short press RESET then release FUNCTION
  • Toggle Easy Wi-Fi - short press POWER button
  • Toggle Hotspot - short press FUNCTION button
  • Accept Hotspot client - short press POWER button
  • Power off - Long press the POWER button until device shuts down
  • Enter multifunction mode - press and hold FUNCTION button (loop cycle: HotspotFirewall AllowFirewall Block → Cancel, each mode wait 2 sec ), release to activate selected function

All shortcut events will be displayed on OOWOW status bar and indicated by LEDs.

Tips to Boot OOWOW

  • Eject your micro SD-card before booting OOWOW (micro SD-card has highest priority)
  • Boot OOWOW from sleep: hold FUNCTION button + short press RESET button + release FUNCTION button
  • Boot OOWOW with power cable: hold FUNCTION button + plug power cable

LED Indication Table

Most system events have corresponding LED indications:

Events Indications
Device starts or reboots White solid
Device power off Red solid
System start in default mode White heartbeat
Network connected White solid
HotSpot mode activated White fast blinking
HotSpot mode ready White solid
HotSpot client pending White and red blinking
HotSpot client accepted White slow blinking
HotSpot mode deactivated White heartbeat
Easy Wi-Fi activated White blinking
Easy Wi-Fi awaits connection White slow blinking
Easy Wi-Fi deactivated White heartbeat
Firewall block incoming Red breathing
Firewall allow incoming White solid, red off
Firewall disabled Red blinking
Image installation progress Red & white blinking
Image installation done White solid, red off

Multifunctional modes:

Events Indications
Hotspot White off
Firewall block incoming White solid, red off
Firewall allow incoming White & red solid
Cancel White blinking


OOWOW provides a universal user interface (terminal mode menu + top status line) for HDMI, WEB, SSH, Serial-UART, etc (all interfaces work simultaneously)

  • Keys: 0-9 A-Z ⇦ ⇨ ⇧ ⇩ Space Enter Esc Tab
  • Mouse (for Web Interface only): select menu items and press buttons

HDMI + Keyboard

A HDMI screen and keyboard is the primary interface modality.

Web Access


Access can be restricted by the firewall

Mobile Navigation

  • Keys: 0-9 A-Z Space Enter
  • Touchscreen: select menu items and press buttons
  • Some virtual keyboard have additional keys: ⇦ ⇨ ⇧ ⇩ Esc Tab

SSH Access

  • root access works by default without password
  • ssh root@vim4-xxxxx.local - plain shell
  • ssh root@vim4-xxxxx.local system - main menu

Access can be restricted by the Firewall.

Serial UART Access

For developers and advanced users.

  • Check how-to Setup Serial Tool
  • Root access works by default without password
  • Type system to enter to main menu, or use other shell commands


For developers and advanced users WIP:

Access can be restricted by the firewall

Dump eMMC by usb network

curl -L -OJ

Dump eMMC by LAN network

curl -L OOWOW_HOST_NAME_OR_IP/api/disk/rdz/mmc.zst -OJ

Write SPI oowow image by LAN network

Write or update SPI-flash firmware by LAN
curl OOWOW_HOST_NAME_OR_IP/shell/write | sh -s - XXX-oowow-latest-spi.img.gz -spi

Write SPI oowow image by USB-otg network

Write or update SPI-flash firmware by USB-otg network
curl | sh -s - XXX-oowow-latest-spi.img.gz -spi


Network connection is required for:

  • OS downloading and installation
  • OOWOW system updates
  • Dynamic syncing of online scripts
  • Remote control over LAN and WLAN

Device Network Name

Every OOWOW device can be accessed remotely via its unique LAN name.


  • device: lowercase device name, e.g. VIM4 → vim4
  • xxxxx: last 5 digits of the device serial number

Network name examples:

  • vim4-00010
  • vim4-00012
  • vim3-12333

Network Name Resolution

Depends on your LAN configuration, for example:

  • vim4-00010 - dns resolver
  • vim4-00010.local - umdns resolving - canonical variant for OOWOW
  • Use device ip address if name resolution doesn't work.
  • OOWOW uses the DHCP hostname.
  • OOWOW uses the MDNS hostname announcement.

Network Name Usage Examples

~$ ping vim4-05690
PING vim4-05690 ( 56(84) bytes of data.
64 bytes from ( icmp_seq=1 ttl=64 time=37.3 ms
~$ ping -c1 vim4-05690.local
PING vim4-05690.local ( 56(84) bytes of data.
64 bytes from ( icmp_seq=1 ttl=64 time=37.3 ms
~$ curl http://vim4-05690.local
~$ curl
~$ curl
~$ ssh root@vim4-05690
~$ ssh root@vim4-05690.local

Ethernet LAN

Ethernet works automatically; just plug in an ethernet cable from your router.

Wireless LAN

User can setup and configure a WLAN connection Network → Wi-Fi → Wi-Fi Select Connection.

  • Wi-Fi configurations are automatically saved and will persist after rebooting.
  • All system configurations will be saved only after a planned shutdown. Check animation.

Easy Wi-Fi

In cases wherein you are unable to configure a WLAN or LAN connection locally on your device, you can share your internet connection from a mobile device (e.g. smartphone) to your single board computer using the Easy Wi-Fi mode.

You can enable the Easy Wi-Fi mode on your device in two ways:

  • Toggle Easy Wi-Fi - short press POWER button
  • Network ⇒ Wi-Fi ⇒ Easy Wi-Fi oowow ⇒ Enable / Disable

Setup a new hotspot from your mobile device with the following configuration:

  • SSID: oowow
  • Password: 12345678

Once OOWOW is in the Easy Wi-Fi mode, it will automatically scan and connect to your Wi-Fi hotspot generated by your mobile device.


You can enable the OOWOW hot-spot feature in two ways:

  • Toggle hotspot - short press FUNCTION button
  • Network ⇒ Hotspot ⇒ Hotspot Enable / Disable

The OOWOW hot-spot will have the following configuration:

  • SSID: vim4-xxxxx ( xxxxx - last 5 digits from device serial number )
  • Password: 12345678

These host names can be used for device access via the hotspot:

Tip: For security reasons, you need to manually accept incoming hotspot connections by short pressing the POWER button once.

Hotspot QR code

Network → Hotspot → Hotspot QR code.

Web access QR code

  • Network ⇒ Hotspot ⇒ Device Web Access QR code
  • Network ⇒ Wi-Fi ⇒ Device Web Access QR code

USB-OTG Network

Connect your device directly to your computer using a USB cable. This feature will interest developers or advanced users; there is only a peer-to-peer network connection, no internet packets will be forwarded to your device.


Network → Firewall Mode:

  • block - Block all incoming connections SECURE
  • allow - Allow incoming connections from local networks RECOMMENDED
  • disabled - Allow all connections, firewall disabled DANGER
  • By default, remote access is blocked by the firewall
  • Easily configure the firewall with the hardware button shortcuts
  • ICMP pings are always allowed, irrespective of firewall mode
  • Hotspot mode allows incoming connections only after pressing the POWER button (device access: or
  • USB-OTG connection is always allowed

Usage Examples

Configure Wi-Fi with Wizard

Check here.

Wi-Fi Connection

Check here.

Easy Wi-Fi Connection

Check here.

Hotspot Mode

Check here.

Hotspot Mode + Ethernet LAN

Internet access provided by LAN ethernet cable, user device access provided by WLAN hotspot.

Hotspot Mode + Wi-Fi WLAN Connection

Internet access provided by WLAN wifi-connection and user device access provided by WLAN hotspot same time.



Device configure KBI

Main menu ⇒ Device configure KBI

KBI is an abbreviation for Khadas Bootloader Instructions, which is developed to fulfill the following purposes:

  • Manage the programmable MCU
  • Carry out low level hardware management
  • Let developers utilize all the features of SBC device

Reset MCU to factory mode

Reset MCU/KBI configuration to default values

This procedure totally safe, and never change eMMC storage content or any other parts.


Setup device boot-mode values:

  • emmc - boot up device from eMMC default
  • spi - boot up device from SPI-flash

For use Android need setup boot-mode to emmc


Security and Privacy

  • OOWOW works only by user demand, and never works in the background
  • OOWOW never sends any private data from your device to the internet
  • By default, remote access to your device is blocked by the firewall


  • Unicode international symbols don’t display properly for HDMI (Wi-Fi network names)
  • IPV6 disabled at this time


  • Automatically looks for updates when internet is connected, user will be notified if new updates need to be applied
  • System updates must be manually approved by the user
  • Don't turn off computer - during update

Download OOWOW

Image Types

  • BOARD-oowow-latest-sd.img.gz - latest oowow image for SD-card or USB-thumb drive
  • BOARD-oowow-latest-spi.img.gz - latest oowow image for SPI-flash
  • BOARD-oowow-latest-spi-upgrade-sd.img.gz - upgrade oowow SPI-flash firmware from SD-card

Filename for Latest OOWOW Version

More information

Last modified: 2023/02/27 01:37 by hyphop