Viswa informs us that the Lemcu.org crew have implemented a purely software based USB peripheral for ARM Cortex M0+ devices and a made a tiny Quick start board for EFM32ZG110 MCU. “This software enables Cortex M0+ devices to act as a Low speed USB device. It includes a lightweight USB & HID Stack and can easily be optimized to consume only 4KB of flash.”
Source files are available on GitHub.
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