PL2303 USB To TTL Module.
Just about all electronics use TTL serial for debugging, bootloading, programming, serial output, etc. But it's rare for a computer to have a serial port anymore. This is a USB to TTL serial cable, with a PL2303 USB/serial chip embedded in the head. It has a 6-pin socket at the end with 5V power and ground, as well as RX, TX, RTS, and CTS at 3V logic levels. These are perfect for use with a Boarduino or other Arduino clones and derivatives, and Useful whenever you want to communicate with a TTL serial device.
PL2303 USB To TTL Module Pinout:
Black - GND
Green - TXD
White - RXD
Red - VCC (5V)
PL2303 USB To TTL Module Data Sheet: PL2303 Windows Driver User Manual v1.16.0