UKM-404 Overview and Use Cases

What Is the UKM-404?

The OREI UKM-404 is a USB 3.2 Gen 1 4x4 USB matrix switch. It allows up to four USB host computers to share up to four USB devices.

The UKM-404 is useful when multiple computers or laptops need access to shared USB peripherals such as a keyboard, mouse, USB drive, camera, table microphone, conferencing soundbar, or other USB device.

The UKM-404 supports USB 3.2 Gen 1 with data transfer speeds up to 5Gbps. It is also backward compatible with USB 2.0 and USB 1.1. The USB-A device ports provide up to 5V/1.5A output power. It is plug-and-play, requires no drivers, and works with Windows, Linux, and macOS. It can be controlled using the front-panel buttons, included IR remote, RS-232, TCP/IP, or Web GUI. 

IMPORTANT — UKM-404 Is a USB Matrix, Not a Video KVM

The UKM-404 is a USB matrix switch.

It does not switch HDMI, DisplayPort, or USB-C video signals.

It is used to route USB devices between USB host computers.

Use this product when you want multiple computers to share USB peripherals.

Do not use this product if you need to switch video displays, monitors, HDMI signals, or DisplayPort signals.

IMPORTANT — USB Ports Do Not Support DP Alt Mode or Power Delivery

The USB 3.2 Gen 1 ports on the UKM-404 are for USB data and USB device sharing.

They do not support:

• DisplayPort Alt Mode 
• USB-C video output 
• Power Delivery charging 

This means the UKM-404 cannot be used as a USB-C video dock, USB-C monitor adapter, or laptop charging dock.

IMPORTANT — Each Host Computer Must Be Connected by USB Type-B

The UKM-404 has four USB host ports.

Each host computer connects to the UKM-404 using a USB 3.0 Type-A to Type-B cable.

The package includes four USB 3.0 Type-A to Type-B cables.

If a computer is not connected to one of the HOST 1–4 ports, the shared USB devices cannot be routed to that computer.

IMPORTANT — Each USB Device Can Be Routed to Any Host

The UKM-404 allows each of the four USB device ports to be assigned to any of the four connected hosts.

For example:

• Device 1 can connect to Host 1 
• Device 2 can connect to Host 3 
• Device 3 can connect to Host 4 
• Device 4 can connect to Host 2 

This is more flexible than a basic USB switch because each USB device can be routed separately.

IMPORTANT — USB 3.2 Gen 1 Speed Depends on Cable Length and Device Support

The UKM-404 supports USB 3.2 Gen 1 data transfer speeds up to 5Gbps.

The manual lists a USB 3.2 Gen 1 5Gbps transmission distance of 3m / 9.8ft over passive cable.

To get USB 3.2 Gen 1 speeds, the connected computer, USB device, and cable must all support USB 3.2 Gen 1 / USB 3.0 performance.

If any part of the setup is USB 2.0, the connection will run at USB 2.0 speed.

IMPORTANT — USB-A Device Ports Provide Up to 5V/1.5A

The USB-A device ports can provide up to 5V/1.5A output power.

This is useful for many USB peripherals, but some high-power USB devices may require more power than the port can provide.

If a USB device is not working reliably, try using a lower-power USB device or a powered USB hub.

IMPORTANT — Web GUI Requires Network Setup

The UKM-404 can be controlled through a Web GUI.

The default IP address is 192.168.0.100.

To access the Web GUI, the computer must be on the same network segment as the UKM-404.

For example, if the matrix IP address is 192.168.0.100, the computer should use an IP address in the same range, such as 192.168.0.104, but not the exact same IP address.

Default Web GUI login:

Ports and Panel Layout

Step-by-Step Setup

1. Connect the included DC 24V power adapter to the UKM-404. 
2. Connect Host 1, Host 2, Host 3, and Host 4 to the UKM-404 using USB 3.0 Type-A to Type-B cables. 
   Examples include desktop PCs, laptops, mini PCs, or workstations. 
3. Connect USB devices to DEVICE 1, DEVICE 2, DEVICE 3, and DEVICE 4. 
   Examples include a keyboard, mouse, USB drive, camera, table microphone, conferencing soundbar, or USB accessory. 
4. Power on the UKM-404. 
5. Use the front-panel DEVICE buttons to assign each USB device to the desired host. 
6. You can also use the included IR remote to select the host for each device. 
7. If using Web GUI control, connect the TCP/IP port to a router, network switch, or computer. 
8. If using RS-232 control, connect the RS-232 port to a PC or control system. 
9. If the unit is installed inside a cabinet or out of IR line of sight, connect the included IR receiver cable to the IR EXT port. 

USB Cable Requirement — Critical

For best USB 3.2 Gen 1 performance, use USB 3.0 / USB 3.2 Gen 1 cables that support 5Gbps data transfer.

The manual lists 3m / 9.8ft as the transmission distance for USB 3.2 Gen 1 5Gbps over passive cable.

Poor-quality or long USB cables may cause:

• USB devices not detected 
• Slow data transfer 
• Intermittent USB connection 
• Keyboard or mouse delay 
• USB drive disconnecting 
• Camera or microphone instability 

For troubleshooting, use the included USB cables or try shorter USB 3.0-rated cables.

Understanding USB Matrix Routing

The UKM-404 is a 4x4 USB matrix.

This means each USB device can be independently routed to one of four USB hosts.

This allows flexible setups where different USB devices can be assigned to different computers at the same time.

Understanding Front-Panel Control

Each DEVICE button controls the routing for that USB device.

For example:

• Press DEVICE 1 to switch Device 1 between Host 1, Host 2, Host 3, and Host 4 
• Press DEVICE 2 to switch Device 2 between Host 1, Host 2, Host 3, and Host 4 

The H1–H4 LEDs show which host is currently assigned to that device.

When the selected host LED lights up, that USB device is connected to that host.

Understanding the IR Remote

The included IR remote can control power and USB routing.

Use the included IR receiver cable if the unit is installed where the front IR receiver cannot see the remote.

Understanding Web GUI Control

The UKM-404 supports Web GUI control through the TCP/IP port.

The Web GUI includes:

• Information page 
• Matrix page 
• USB page 
• Network page 
• System page 

The Information page shows basic information such as model, firmware version, and network settings.

The Matrix page allows users to select the host for Device 1, Device 2, Device 3, and Device 4. It also supports saving, recalling, and clearing up to 8 presets.

The USB page allows users to rename each host and device.

The Network page allows users to modify IP mode, IP address, gateway, subnet mask, Telnet port, and domain name.

The System page allows password changes, panel lock, beep on/off, serial baud rate changes, reboot, factory reset, and firmware update.

Understanding Presets

The UKM-404 supports up to 8 presets.

Presets allow you to save a group of USB routing settings and recall them later.

For example, you can save a setup where:

This is useful for meeting rooms, shared workstations, conference systems, labs, and control rooms where users need to quickly recall common USB routing setups.

Understanding Network Settings

The default network settings shown in the manual are:

The IP address can be checked using the RS-232 command get ip addr or get ipconfig.

If the UKM-404 is set to DHCP, the router will assign an IP address automatically.

If it is set to Static, the IP address, gateway, subnet, and Telnet port can be changed manually.

RS-232 Control

The UKM-404 supports RS-232 command control.

Default RS-232 settings:

RS-232 commands can control:

• Power on/off 
• Beep on/off 
• Front-panel lock 
• Baud rate 
• Reboot 
• Factory reset 
• USB device-to-host routing 
• Save / recall / clear presets 
• Network configuration 
• IP mode 
• IP address 
• Subnet mask 
• Gateway 
• TCP/IP port 
• Telnet port 

Example command function:

Understanding USB Device Power

Each USB-A device port can provide up to 5V/1.5A.

This can support many standard USB devices, including:

• Keyboard 
• Mouse 
• USB drive 
• Table microphone 
• USB camera 
• Conferencing soundbar 
• Basic USB accessories 

Some high-power USB devices may need their own power supply or a powered USB hub.

If a device works directly on the computer but does not work through the UKM-404, check the USB cable, power requirement, and routing selection.

What Host Devices Is the UKM-404 Compatible With?

The UKM-404 can connect to USB host devices such as:

• Windows PCs 
• Linux computers 
• macOS computers 
• Laptops 
• Desktop PCs 
• Mini PCs 
• Workstations 
• Conference room computers 
• Control room computers 

The computer must connect to one of the HOST 1–4 USB Type-B ports.

What USB Devices Is the UKM-404 Compatible With?

The UKM-404 can share USB devices such as:

• Keyboard 
• Mouse 
• USB flash drive 
• USB hard drive 
• USB camera 
• USB microphone 
• Table microphone 
• Conferencing soundbar 
• Printer 
• Scanner 
• USB audio device 
• Other USB peripherals 

For USB 3.2 Gen 1 speeds, the USB device, USB cable, and host computer must support USB 3.2 Gen 1 / USB 3.0.

Frequently Asked Questions

Q: What is the OREI UKM-404 used for? 
A: The UKM-404 is used to share up to four USB devices between up to four computers or laptops.

Q: Is the UKM-404 a KVM switch? 
A: No. The UKM-404 is a USB matrix. It switches USB devices between computers, but it does not switch video displays.

Q: Does the UKM-404 support HDMI or DisplayPort video? 
A: No. It does not support HDMI, DisplayPort, or any video switching.

Q: Does the UKM-404 support USB-C video or DP Alt Mode? 
A: No. The USB 3.2 Gen 1 ports do not support DisplayPort Alt Mode.

Q: Does the UKM-404 support USB Power Delivery charging? 
A: No. The USB ports do not support Power Delivery charging.

Q: How many host computers can I connect? 
A: You can connect up to four host computers.

Q: How many USB devices can I connect? 
A: You can connect up to four USB devices.

Q: Can each USB device go to a different computer? 
A: Yes. Each USB device can be routed independently to Host 1, Host 2, Host 3, or Host 4.

Q: Does the UKM-404 require drivers? 
A: No. It is plug-and-play and does not require drivers.

Q: What operating systems are supported? 
A: The manual lists compatibility with Windows, Linux, and macOS.

Q: What USB speed does it support? 
A: It supports USB 3.2 Gen 1 data transfer up to 5Gbps.

Q: Is it backward compatible with USB 2.0? 
A: Yes. It is backward compatible with USB 2.0 and USB 1.1.

Q: How much power do the USB-A device ports provide? 
A: The USB-A device ports provide up to 5V/1.5A.

Q: Can I connect a USB camera and microphone? 
A: Yes. USB cameras, microphones, and conferencing devices can be connected as long as they are standard USB devices and are within the power and bandwidth limits.

Q: How do I switch Device 1 to Host 3? 
A: Press the Device 1 button until the H3 indicator lights up, or use the IR remote and press H3 under Device 1.

Q: How do I know which host a device is connected to? 
A: The H1–H4 LEDs under each device section show which host is currently selected.

Q: Can I control the UKM-404 from a browser? 
A: Yes. The UKM-404 supports Web GUI control through the TCP/IP port.

Q: What is the default Web GUI IP address? 
A: The default IP address is 192.168.0.100.

Q: What is the default Web GUI login? 
A: Select username Admin and enter password 1234.

Q: Can I rename the hosts and devices? 
A: Yes. The Web GUI USB page allows each host and device to be renamed.

Q: Can I save presets? 
A: Yes. Up to 8 presets can be saved, recalled, or cleared through the Web GUI or RS-232 commands.

Q: Does the UKM-404 support RS-232 control? 
A: Yes. It supports RS-232 command control.

Q: What is the default RS-232 baud rate? 
A: The default RS-232 baud rate is 115200.

Q: What should I do if the Web GUI does not open? 
A: Make sure the computer and UKM-404 are on the same network segment. Check the current IP address using RS-232 command get ip addr or get ipconfig.

Q: What should I do if a USB device is not detected? 
A: Check that the device is connected to one of the DEVICE ports, confirm the selected host is powered on and connected to the matching HOST port, try a shorter USB cable, and check whether the device needs more power.

Q: Does the UKM-404 need external power? 
A: Yes. Connect the included DC 24V power adapter.