In this latest update, I'm excited to introduce a new firmware that prioritizes energy efficiency. It leverages the fact that the TinyML board has a neural network accelerator (NDP101) and host processor (ATSAMD21G18) as two separate devices. The NDP101 can process the input audio with extremely low power consumption. While NDP101 is processing the audio, the host MCU can be in sleep mode until the moment the NDP101 recognizes the desired sound pattern. If this happens, the NDP101 wakes up the host MCU via a dedicated interrupt pin. As the host MCU takes the largest portion of energy, this approach will dramatically reduce total power consumption.

Before the low-power mode was implemented the total current draw was about 15mA. It's now been impressively reduced to under 2mA ! This current is low enough to power the whole device with a small solar panel (keep the battery charged). FW is available on GitHub – Please follow the readme file for further instructions. You can also watch the demonstration video on YT.