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# Introduction
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We started with a U.S. Solid Smart Motorized Ball Valve (Model USS-MSV00087). Due to the reliance on an online application, we approached this as a hardware base. Reverse engineering was successful with the identification of key components as follows:
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## Motor control
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- RZ7888 (2A motor control driver IC, SOP-8 package)
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- [RZ7888](https://www.micros.com.pl/mediaserver/UIRZ7888_0001.pdf) (2A motor control driver IC, SOP-8 package)
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- Activation of the close function of the valve via Y1 NPN transistor (noted in purple below) - tied to pin 1 of the motor control and controlled by pin 6 of the control board
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- Activation of the close function of the valve via Y1 NPN transistor (noted in orange below) - tied to pin 2 of the motor control and controlled by pin 5 of the control board
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- Both transistors are held in the open position with their bases held high by 10Kohm resistors to the 3.3v rail
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