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An external button can be connected to the pin 1 (3V3) and 3 (RXD) of the UART header (J9). Pulling pin 3 (RXD) high momentarily toggles the EPM. External button is supported in firmware builds starting from March 2017.
LED indication
Status LED
This LED indicator shows the status of the device derived from the continuous self-diagnostics, according to the UAVCAN node status code:
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