The PL2303HX is a USB to UART TTL (Transistor-Transistor Logic) converter module that allows communication between a computer or other USB-equipped device and a UART device through a USB port.
The HW586 is maximum battery capacity range: 9999Ah (1Ah = 1000mAh) greater value by shifting the decimal point to switch, when the display is less than 10Ah X.XXX, as shown above to achieve 10Ah XX.XX, and so on.
The PCF8591 is a monolithic single supply low power 8-bit CMOS data acquisition device. PCF8591 has four analog inputs, one analog output and a serial I2C bus interface.