USB, is the English Universal Serial BUS (Universal Serial Bus) acronym, is an external bus standard, a specification for a computer with an external device connection and communication, is used in the field of PC interface technology.
          Why use USB it? PC-limited I / O slots can not meet the growing needs peripherals; USB is generated for this purpose. USB is a computer peripheral device is connected so that the standardization, simplification of the interface, and its specifications by Intel (Intel), NEC, Compaq, DEC, IBM (Business Machines Corporation), Microsoft (Microsoft), Northern Telecom contact making. In USB mode, all peripherals are outside of the chassis, connecting peripherals without having to re-open the case; allow hot-swappable peripherals without having to turn off the system, to achieve true plug and play.

          A USB (USB converter) interface can theoretically support 128 devices, but is still unable to reach this figure. In fact, for a computer, the connected peripheral peripherals rarely have more than 10, so this number is enough for us to use. USB for PC peripheral expansion provides a good solution.

         UT-2003A is a universal USB to RS485 / 422 converter, no external power supply, built-in optical isolator and DC / DC power supply isolation module. Compatible USB, RS-422, RS-485 standard, the ability to convert single-ended USB signals to balanced differential RS-422 or RS-485 signals, I converter with zero delay automatic internal transceiver conversion, unique / O circuit automatically controls the data flow direction, without any handshaking signals (such as RTS, DTR, etc.) without the jumper settings to achieve full-duplex (RS-422), half-duplex (RS-485) mode switch, plug and play. to ensure that it meets all existing hardware through software and interface.
UT-2003A optical isolation interface converter for point to point, multipoint communications to provide reliable connectivity, multipoint each Port port allows connection 128 RS-422 or RS-485 interface devices, data communication speed 300-128000bps, with a power indicator and data traffic lights can indicate fault conditions, support of communication with a USB to RS-422, USB to RS-485 converter.

  Compliance USB1.1,1.0 standard, backward compatible with USB2.0
  Supports RS-422/485 universal interface, no jumper
  RS-422/485 interface DB9 needle
  Enhanced optical isolation (isolation voltage 2.5KVrms / 500VDC insulation), dedicated DC / DC module,
  RS-485/422 provides 600W per line lightning protection, surge, + / - 15KV ESD protection and prevention of common ground disturbance
  Data (TXD) automatic flow control, zero-latency design
  Communication rate: 300-128000bps
  Support automatic handshake protocol
  Supports remote wakeup and power management
  Power input: AC100V-240V / 50 ~ 60Hz
  Power consumption: 12W maximum
  Dimensions: 490mmX201mmX43mm
  Use of the environment: -25 ℃ to 70 ℃, relative humidity of 5% to 95%
  Support Win98 / Win2000 / WinXP / Vista / Win7 / Linux, etc.