M5Stack CardKB2 Keyboard Unit (ESP32-C61)
M5Stack CardKB2 Keyboard Unit (ESP32-C61)
The M5Stack CardKB2 Keyboard Unit is a compact card-sized input module built for portable text entry, embedded interaction, and wireless control workflows. Powered by the ESP32-C61HF4, it combines a 42-key keyboard layout with modern wireless capability, compact physical dimensions, and flexible connectivity options that make it well suited for handheld controllers, maker projects, educational systems, and custom human-machine interface builds.
According to the official M5Stack product page, CardKB2 supports four communication modes: I2C, UART, BLE HID, and ESP-NOW. It also includes a USB Type-C port for power and firmware flashing, a HY2.0-4P expansion interface, an onboard RGB indicator LED, and dedicated Reset and Boot buttons. Its slim format and lightweight design make it especially practical for on-the-go and embedded use.
Features
- ESP32-C61HF4 based: Uses a RISC-V single-core MCU running at 120MHz with 4MB flash.
- 42-key compact keyboard: Provides portable text input in a card-sized form factor.
- Four communication modes: Supports I2C, UART, BLE HID, and ESP-NOW for flexible integration.
- Wireless ready: Built-in 2.4GHz Wi-Fi 6 and BLE support for modern embedded control workflows.
- USB Type-C connectivity: Used for power supply and firmware flashing.
- HY2.0-4P interface: Adds convenient expansion for M5Stack and Grove-style workflows.
- RGB status indicator: Onboard RGB LED provides keyboard status indication.
- Portable and lightweight: Card-sized design makes it suitable for handheld and mobile projects.
Specifications
| Parameter | Value |
|---|---|
| Product Name | M5Stack CardKB2 Keyboard Unit (ESP32-C61) |
| SoC | ESP32-C61HF4, RISC-V 32-bit single-core, 120MHz |
| Flash | 4MB |
| Wireless | 2.4GHz Wi-Fi 6, BLE |
| Communication Modes | I2C, UART, BLE HID, ESP-NOW |
| Keys | 42-key keyboard, 1x Reset button, 1x Boot button |
| USB | USB Type-C for power and firmware flashing, default log output 115200bps @ 8N1 |
| Indicator | 1x RGB LED |
| Expansion Interface | 1x HY2.0-4P |
| Power Supply | USB Type-C / DC 5V |
| Standby Power | 5V @ 19.31mA under Grove interface power supply conditions |
| Product Size | 84.7 x 54.3 x 1.0mm |
| Product Weight | 22.4g |
| Package Size | 170.0 x 120.0 x 8.0mm |
| Gross Weight | 28.9g |
Applications
- Portable device text input
- Embedded human-machine interaction
- Wireless control terminals for IoT devices
- Maker and educational programming projects
- Compact input interfaces for custom handheld systems
Hardware Highlights
- Card-sized design: Easy to integrate in space-constrained portable builds.
- Multi-mode communications: Can be adapted for wired or wireless keyboard workflows.
- Direct firmware access: USB-C and onboard buttons simplify flashing and setup.
- M5Stack ecosystem fit: HY2.0-4P interface helps it integrate cleanly with modular M5Stack hardware.
Packing List
- Unit CardKB2 x1
- HY2.0-4P Grove Cable (20cm) x1
FAQ
What wireless functions does CardKB2 support?
It supports Wi-Fi 6 and BLE, with communication modes including BLE HID and ESP-NOW.
How many keys does it have?
It uses a 42-key keyboard layout and also includes Reset and Boot buttons.
Can it be used with wired communication?
Yes. It supports both I2C and UART in addition to wireless modes.
What port is used for power and firmware flashing?
It uses a USB Type-C port.
Is it suitable for embedded or handheld projects?
Yes. Its card-sized format and low weight make it especially suitable for portable embedded systems.
Where can I find the official documentation?
You can review the official product and documentation pages from M5Stack for setup and development details.
Resources
- Official M5Stack product page - Product overview and specifications.
- M5Stack documentation - Product documents and usage references.
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2.1 Germany Domestic Shipping
| Shipping Method | Order Value | Cost | Est. Delivery |
|---|---|---|---|
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|
DHL Paket (Faster Delivery) |
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|
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|---|---|---|---|
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| Region | Shipping Method | Order Value | Cost | Est. Delivery |
|---|---|---|---|---|
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|---|---|
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