Comu
cheyao·comu·hardware/comu.kicad_pcb
About the Comu PCB
Comu is an open source RISC-V PCB design by cheyao, published on GitHub under the SHL-2.1 license. It is a 2-layer board measuring 9.4 × 13 mm, with 9 components from 6 distinct parts.
Its main chip is the CH32V203F8U6, from the RISC-V family. Other key parts include the XC6206PXXXMR. By type, the board carries 3 capacitors, 2 ICs, 2 diodes and 2 resistors.
From the project
A bite-sized CH32V203 board that fits inside your USB port.
A bite-sized CH32V203 board that fits inside your USB port.
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Comu is a tiny CH32V203 RISC-V computer that fits inside a USB port. It is user programmable, fitted with a custom bootloader, has four captive touch buttons and two LEDs. The board is supported by ch32fun, allowing easy and lightweight RISC-V bare-metal development.

Main components on the Comu
Comu bill of materials (BOM)
9 components, 6 distinct parts — part numbers from the project's BOM.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 1 | CH32V203F8U6 | QFN-20-1EP_3x3mm_P0.4mm_EP1.65x1.65mm | U1 |
| 1 | XC6206PXXXMR XC6206PxxxMR | SOT-23-3 | U2 |
| 2 | LED | LED_0402_1005Metric | D1, D2 |
| 2 | 1UF 1uF | C_0402_1005Metric | C1, C2 |
| 1 | 100NF 100nF | C_0402_1005Metric | C3 |
| 2 | 1k | R_0402_1005Metric | R1, R2 |
Comu design files
The KiCad project lives in the cheyao/comu repository on GitHub; these links point at the commit this page was built from.
Comu: common questions
What microcontroller does the Comu use?
The Comu is built around the CH32V203F8U6, from the RISC-V family.
How big is the Comu PCB?
The Comu measures 9.4 × 13 mm, has 2 copper layers and is 0.6 mm thick.
How many components are on the Comu?
9 components, from 6 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.
Where can I download the Comu design files?
From the cheyao/comu repository on GitHub, which has the KiCad layout, the schematic and the BOM; the links under Design files point to each one.
Can I use the Comu design in my own project?
It is published under SHL-2.1, which limits how it may be reused; read the license before building on it.
Can I test firmware for the Comu without the hardware?
Yes. HardLabs builds a simulation of the board from its netlist and BOM, so you can run and debug RISC-V firmware against it before you order a PCB.
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