This driver package installs the necessary software to enable communication between a PC and a device connected via a Prolific PL2303-based USB-to-Serial adapter. Version 3.3.3.114 is a legacy driver intended for older operating systems and older PL2303 chip revisions (specifically PL2303 HXA, XA, or older revisions).

Background Prolific Technology Inc. produces the PL-2303 chipset used in many inexpensive USB-to-RS232 adapters. Manufacturers and resellers bundle Prolific-based dongles to provide serial connectivity for instruments, industrial gear, embedded devices, CNC controllers, and serial consoles. Driver version 3.3.3.114 is one of the stable Prolific USB-to-Serial driver releases used to create a virtual COM port in Windows.