Note: Signal strength indication: when the signal is strong the signal indicator shows green, when the
signal is moderate the indicator shows yellow, and when the signal is weak the indicator shows red.
Power indication: when the power is sufficient the indicator shows green, when the power is average the
indicator shows yellow, when the power is low, the indicator shows red,and when charging the power
indicator flashes, when charging is complete, the power indicator stops flashing and the green light is
always on.
2.2 GPIO Definition
Signal strength Power indication