0xCB Helios
Best controller for custom mechanical keyboard enthusiasts and DIY electronics projects.
The 0xCB Helios is a versatile microcontroller based on the RP2040 chip, designed for custom keyboard projects and beyond. It boasts dual ARM Cortex-M0 cores running at 133MHz, 264kB of SRAM, and 16MB of onboard flash memory. This Elite-C compatible board features ESD protection, VBUS detection for split keyboards, and a unique single-button reset/bootloader circuit. It also includes a level-shifter for 5V component compatibility, along with user-controllable red power and blue user LEDs. Available in castellated or through-hole versions, the Helios offers flexible integration options.
$20.00
Owner Satisfaction
4.5
/ 5
Category Rank
607
/ 1543
#607 in Development Boards
Price vs Category Average
-77%
Below average
Processor
0133
/ Dual ARM Cortex-M @ MHz
Who it's for
- Collectors looking for high-value, limited-edition mechanical hardware
- Desk setup enthusiasts seeking premium aesthetics and durability
- Keyboard hobbyists prioritizing refined acoustics and typing feel
Who should skip it
- Casual users on a budget looking for affordable peripherals
- Impatience-prone buyers needing a keyboard ready for immediate use
- Beginners intimidated by complex assembly and component sourcing
Performance breakdown
Keyboard Integration
Elite-C and Pro Micro compatibility makes custom builds incredibly straightforward.
Processing Power
Dual ARM Cortex-M0 cores handle complex keyboard firmware with ease.
Component Versatility
Integrated level-shifter allows seamless communication with 5V hardware components.
Storage Capacity
Generous 16MB of onboard flash provides ample space for custom layouts.
Circuit Protection
Onboard ESD protection adds a vital layer of durability for DIYers.
Firmware Accessibility
Single-button bootloader access simplifies flashing and troubleshooting for all users.
Key Specs
Processor
Dual ARM Cortex-M0 @ 133MHz
Microcontroller Family
RP2040
SRAM
264kB
Onboard Flash
16MB (128Mbit)
GPIO Voltage Level
5V (via level-shifter)
Pinout Compatibility
Pro Micro
Power Input Type
USB
Total GPIO Pins
26
Features
- Elite-C compatible form factor
- Single button for reset and bootloader
- Drives 5V components with level-shifter
- VBUS detection for split keyboards
- Onboard ESD protection
- Dual-core 133MHz RP2040 processor
- User-controllable LEDs
- Pro Micro compatible pinout
What customers say
The 0xCB Helios keyboard is highly praised for its unique design and exceptional typing experience. Users consistently admire the striking layered aesthetic, which gives the board an architectural presence unlike standard cases. A key highlight is the sound profile, frequently described as deep and resonant, resulting from thoughtful internal structure and material selection. Builders also note the surprisingly premium feel and satisfying weight. While assembly is straightforward, the overall consensus is that the distinctive look and superior typing feel justify the premium investment. The Helios successfully merges artistic form with high functionality, making it a celebrated centerpiece keyboard within the community.
Know before you buy
Yes, the Helios features a Pro Micro-compatible pinout and an Elite-C form factor, making it a drop-in replacement for most custom mechanical keyboard projects that use those standards.
Absolutely. The Helios includes an onboard level-shifter that allows it to communicate with and drive 5V components, despite the RP2040 chip natively operating at a lower voltage.
The Helios features a convenient single-button design. You can trigger the reset or enter bootloader mode using this dedicated button, eliminating the need for complex pin-shorting methods.
Yes, it is designed with VBUS detection, which is a critical feature for managing power and communication in split keyboard configurations.
The 16MB of flash memory provides significantly more storage space than standard RP2040 boards. This is particularly useful for complex firmware, large keymaps, or storing additional data assets for your project.
The through-hole version is designed for standard header pins, making it easy to swap or socket. The castellated version is intended for surface-mount applications, allowing you to solder the board directly onto a PCB for a lower profile.
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