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6.4. Bootloader LED behavior
This section documents the behavior of the P-Star’s LEDs while it is in bootloader mode.
If an active USB connection is present, the green LED will blink to indicate whether the device has reached the USB Configured state. If the device has not reached the Configured state, the green LED will blink on and off with a 50% duty cycle and a period of about 1.4 seconds. If the device has reached the Configured state, then it will do a double-blink every 1.4 seconds.
The yellow LED is usually on solid, but it will blink quickly whenever a USB command is received.
If USB is not connected or the USB connection is in suspend mode, the bootloader will briefly blink the green LED about once per second, and the yellow LED will be off.