EPOMAKER SKYLOONG SK21 Numpad User Manual

1. Introduction

This manual provides detailed instructions for the setup, operation, and maintenance of your EPOMAKER SKYLOONG SK21 Numpad. The SK21 is a 21-key programmable numpad featuring PBT keycaps, RGB backlighting, and a Type-C interface, designed for enhanced productivity and customization.

Figure 1: Front view of the EPOMAKER SKYLOONG SK21 Numpad, showcasing its compact design and illuminated keys.

2. Package Contents

Please verify that all items are present in your package:

• EPOMAKER SKYLOONG SK21 Numpad
• USB Type-C Cable

3. Setup Guide

3.1 Connecting the Numpad

1. Locate the USB Type-C port on the back of the SK21 Numpad.
2. Connect one end of the provided USB Type-C cable to the numpad.
3. Connect the other end of the USB cable to an available USB port on your computer.
4. The numpad will automatically be recognized by your operating system (Windows, macOS, Android).

Figure 2: The USB Type-C interface on the SK21 Numpad, illustrating the connection point for the included cable.

3.2 Driver and Software Installation

To unlock the full customization potential of your SK21 Numpad, including RGB lighting effects, macro programming, and key remapping, it is recommended to download and install the official EPOMAKER SKYLOONG software driver. Please visit the official EPOMAKER website for the latest driver version.

4. Operating Instructions

4.1 Basic Numpad Functionality

Once connected, the SK21 Numpad functions as a standard numeric keypad. Ensure the 'Num Lock' function is active on your main keyboard or the numpad itself for numeric input. The numpad's 'Num' key (often labeled 'Num Lock') controls this function.

4.2 RGB Backlight Control

The SK21 Numpad features 16.8 million colors RGB backlighting with various effects. You can control and customize these effects through the dedicated software driver. The software allows for rhythm and sound lighting combinations, and additional lighting effects can be downloaded and applied.

4.3 Macro and Key Customization

The SK21 Numpad offers extensive customization with three programmable layers (FN1, FN2, FN3). These layers allow you to assign macros or remap keys for specific tasks, gaming, or professional workflows. The onboard 8M Flash Memory saves your settings, ensuring they persist even when the numpad is disconnected.

• Accessing Layers: The 'Fn' key (typically F3 on the numpad) is crucial for accessing these layers. Pressing 'Fn' + '1', 'Fn' + '2', or 'Fn' + '3' will switch between the custom layers.
• Driver Mode: 'Fn' + '0' may activate a 'driver mode' where the numpad is controlled directly by the software.
• Returning to Standard Mode: Pressing 'Fn' + the currently active layer number will typically return the numpad to its standard numeric input mode.
• Important Note: The 'Fn' key itself (F3) is generally fixed in its position and cannot be remapped.

Use the EPOMAKER SKYLOONG software to program macros and remap keys within these layers. The software provides a user-friendly interface for these advanced settings.

5. Features Overview

• 21-Key Functional Numpad: Engineered with a 21-key PCB and a 32-bit MCU, providing ample space and processing power for demanding tasks and full programmability.
• OEM PBT Keycaps: High-quality PBT keycaps with an OEM profile offer superior durability, oil-resistance, and color retention compared to ABS keycaps. Shine-through legends ensure visibility of backlighting.


Figure 3: Detail of the OEM PBT double-shot keycaps, highlighting their construction and shine-through capability.

• 16.8 Million Types RGB Backlight: Features extensive RGB lighting customization with various effects, rhythm, and sound lighting combinations, all manageable via the software driver.
• 3 Fn Macros Customization: Offers three definable layers (FN1/FN2/FN3) for comprehensive macro and key remapping. Settings are saved to built-in flash memory for offline use.
• Superior Hardware Architecture: Integrates a 32-bit M3 MCU chipset with onboard 8M Flash Memory and a 3-channel 256 professional-level RGB color management chip for seamless programming and macro customizations.
• Hot-Swappable Optical Switches: The SK21 Numpad supports hot-swappable optical switches, allowing users to easily change switches without soldering to customize typing feel.


Figure 4: Demonstration of the hot-swappable optical switch feature, showing a switch being removed from the PCB.

6. Maintenance

6.1 Cleaning

To clean your numpad, disconnect it from your computer. Use a soft, lint-free cloth slightly dampened with water or a mild cleaning solution. For keycaps, you may use a keycap puller to remove them and clean them separately with water and mild soap, ensuring they are completely dry before reattaching.

6.2 Keycap and Switch Replacement

The PBT keycaps can be removed using a standard keycap puller. For optical switches, use the provided switch puller (if included) to carefully remove and replace switches. Ensure proper alignment when inserting new switches to avoid bending pins.

7. Troubleshooting

• Numpad Not Responding: Ensure the USB Type-C cable is securely connected to both the numpad and your computer. Try a different USB port or cable.
• Keys Not Registering: Check if 'Num Lock' is active. If specific keys are not working, and you have hot-swappable switches, try reseating or replacing the switch.
• RGB Backlight Not Working/Incorrect: Verify that the numpad is connected and the software driver is installed. Use the software to adjust lighting settings.
• Macros Not Saving/Working: Ensure you have saved your macro settings within the software. Confirm you are in the correct programmable layer (FN1, FN2, or FN3). Remember that the 'Fn' key itself cannot be remapped.
• Software Issues: If the software is sluggish or crashes, try restarting your computer and reinstalling the latest driver from the official EPOMAKER website.

8. Specifications

9. Warranty and Support

EPOMAKER products typically come with a limited warranty. For specific warranty details, return policies, and technical support, please refer to the documentation included with your purchase or visit the official EPOMAKER website. Keep your proof of purchase for warranty claims.