The UC4854 is the converter that transform the USB port to your computer into four asynchronous RS-422 or RS585 serial ports. This unit supports RS422/485 Auto Detect & Switch technology so when there is defined activity on the connected serial device, the converter automatically switches to the active serial port. Compatible with both USB 1.1 and 2.0, these devices can transfer data up to 115.2Kbps. Because UC4854 operates with plug-and play ease(under Windows) or with the provided Linux driver via a USB port interface, it doesn't require any IRQ, DMA or I/O addressing resources. Embedded electrostatic surge protection, prevents damage to serial devices caused by air discharges as high as 15,000 volts.