Devices and Parts List

Compatible Devices (comparative table)¶

Device	M5StickV	Maix Amigo	Maix Dock	Maix Bit	Yahboom k210 module	Maix Cube	WonderMV
Price range	US$ 50-55	US$ 50-85	US$ 27-35	US$ 32-42	US$ 45-61	US$ 34-49	US$ 58-86
Screen size / resolution	1.14" / 135*240	3.5" / 320*480	2.4" / 240*320	2.4" / 240*320	2" / 240*320	1.3" / 240*240	2" / 240*320
Brightness control
Device size	482422mm	1046317mm	985918mm	698441mm	574117mm	404016mm	594117mm
Touchscreen		Capacitive			Capacitive		Capacitive
Camera	`OV7740`	`OV7740` rear `GC0328` front	`GC0328`	`OV2640` or `OV5642`	`OV2640` (VER:1.0) or `GC2145` (VER:1.1)	`OV7740`	`GC2145`
Battery	200mAh	520mAh				200mAh
Requirements	None	None	Rotary encoder 3D printed case Soldering Assembly	Buttons 3D printed case Soldering Assembly	None	None	None
Warnings				Camera has lens distortion	Micro USB	3-Way button

: The USB-C ports on the M5StickV and WonderMV lack the pull-up resistors required for host (computer) recognition and power. If you don't have a USB-A port available, you can use a USB hub between your computer's USB-C port and these devices.

: Some Amigo screens have inverted X coordinates, others display colors differently. For more info see Troubleshooting.

: Some Maix Dock units are shipped with soldered pin connectors, which prevent them from fitting into the 3D-printed case. Certain boards also come with built-in Wi-Fi.

: WonderMV may restart when certain SD cards are inserted. See Why does my WonderMV reboot.

All devices feature Kendryte K210 chip: 28nm process, dual-core RISC-V 64bit @400MHz, 8 MB high-speed SRAM, DVP camera and MCU LCD interface, AES Accelerator, SHA256 Accelerator, FFT Accelerator.

M5StickV¶

Krux was first ported to this device in March 2022. Featuring the smallest screen size and resolution, it also includes a built-in battery. Refer to the USB-C recognition warning above for important notes. Below is a list of distributors where it can be found:

Maix Amigo¶

Krux has supported this device since its second version in August 2022. It offers the largest screen size and resolution, a touchscreen, and a built-in battery. Below is a list of distributors where it is available:

Yahboom k210 module¶

Supported by Krux since March 2024, this device features a touchscreen and comes with a compatible 32 GB card, a USB card reader, one PH2.0 4-pin male-to-male connector, and a PH2.0 female adapter for connecting to a thermal printer. Below is a list of distributors where it is available:

Maix Cube¶

Supported by Krux since July 2024, this device features the second smallest screen size and resolution, a 3-way button, and a built-in battery. Below is a list of distributors where it is available:

WonderMV¶

Supported by Krux since September 2024, this touchscreen device features a metal backplate and includes a compatible 32 GB card, a USB card reader, and two 5264 4-pin connector male-to-male cables for connecting to a thermal printer. Refer to the USB-C recognition warning and the SD card warning above for important notes. The following distributors offer this device:

Maix Dock and Maix Bit¶

For DIY enthusiasts, Krux has supported the Maix Dock and Maix Bit since August 2022. These kits include a board and screen but require you to source a rotary encoder or buttons separately and assemble the device yourself. Some Maix Dock boards also include Wi-Fi.

Here are example builds with instructions on how to recreate them:

Available from these distributors:

Other Parts¶

USB-C or Micro USB Charge Cable¶

This will come with the device. It will be necessary to power, charge the device (if it has battery) and to initially flash the firmware.

(Optional) MicroSD Card¶

We cannot guarantee that a microSD card is compatible and will work in your device; you'll need to test it on the device to be sure, read the Troubleshooting for more info. Yahboom will come with a compatible 32G card. The size of the SD card isn't important; anything over a few megabytes will be plenty.

(Optional) TTL Serial Thermal Printer¶

Warning/Disclaimer: This feature is intended for individuals with experience in electronics tinkering and soldering.

Krux has the capability to print all QR codes it generates, including those for mnemonics, xpubs, wallet backups, and signed PSBTs, using a locally-connected thermal printer via its serial port.

Many TTL serial thermal printers may be compatible, but currently, the Goojprt QR203 has the best support (except this printer only supports ASCII or Chinese characters, non-ASCII characters will be printed as Chinese). The Adafruit printer starter pack can also be a convenient option to get started, as it includes all the necessary components for printing (except the conversion cable). To ensure proper functionality, enable the printer driver in settings, set the Tx pin and baud rate value to either 19200 or 9600 (depends on the printer), as explained in this Adafruit printer tutorial. You will need to connect the device's Tx to the printer's Rx and device's ground to the printer's ground, do not connect any other pins because a wrong connection may damage your device. The printer requires a dedicated power supply, typically with an output of 5 to 9V (or 12V) and capable of supplying at least 2A. For more information, see this discussion.

Conversion Cable¶

To connect the printer to M5StickV, Amigo or Cube, you will need a grove conversion cable with a 4-pin male Grove connector on one end (to connect to the device) and 4-pin male jumpers on the other end (to connect to the printer). Check your device and printer model connection first, Yahboom comes with PH2.0 4Pin female connector; Dock and Bit doesn't have a connector; WonderMV comes with Molex 51004 4-pin connector (used with smart servo). For a more reliable connection, it is recommended to cut and solder the wires of your custom cables instead of using jumpers. Here we have a description of some inter-integrated circuit (I2C) connector standards.