Standard Raspberry Pi 40PIN GPIO extension header, supports Raspberry Pi series boards. Adopts the combination scheme of SC16IS752, SP3485 and SP3232, converts SPI to one RS485 and one RS232 ^^ Onboard resettable fuse and protection diodes, ensure the stable output of RS485 current and voltage, prevent over-current and over-voltage, improve shock resistance ^^ Onboard TVS (Transient Voltage Suppressor), can effectively suppress surge voltage and transient spike voltage in the circuit, lightningproof & anti-electrostatic ^^ Breakout SPI control pins, for connecting with Arduino and other host control boards ^^ Comes with development resources and manual (examples in C and Python)