Over the years, we have seen several tiny “omu” USB boards that share this “fits-in-a-USB-port” form factor. It started with the Tomu, based on a Silicon Labs EFM32 Cortex-M0+, followed by the Fomu with a Lattice iCE40 FPGA, Qomu with an EOS S3 Cortex-M4F MCU and FPGA, and the Somu, a tiny FIDO2 security key.Icy Electronics has now introduced Comu, another tiny development board based on the WCH CH32V203 144 MHz RISC-V MCU. While measuring just 13 x 9.4 mm (slightly smaller than a microSD card), the board still packs two white LEDs, four capacitive touch buttons, and six GPIOs exposed through test pads. It is designed for bare-metal programming, custom USB HID projects, and USB packet experimentation.Comu specifications:
MCU – WCH CH32V203V203F8
CPU – Single-core 32-bit RISC-V clocked at 144MHz
Memory – 20KB SRAM
Storage – 224KB Flash (64KB of 0-wait Flash and 160KB of normal Flash)
