There is 4 LED bar graph display to show estimate battery level and a single button to control On/off, Different Level of Brightness , and Select one , all or few of LED boards to litup.
there is not much to describe in term of schmeatic and firmware as all the Firmware and Schmeatic aer already on my github account.User interface panel is made out of PCB with 4 battery status LED a port for solar panel Connector and a control switch.
when battery is chargin LED status displayed accordingly and when battery is discharging led status updated accordingly.
i have a good quality connector for solar panel connection and after using it for few months i can say it worth every penny i spent on the connector.
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