A universal interface driver application specific integrated circuit (UIDA) for a data reading device which supports multiple host interface configurations through the use of shared communications lines. In one application, the UIDA is a 32 or 44-pin TQFP chip located in a bar code scanner, or other data reader, connected to a host processing device such as a computer terminal. The scanner reads and decodes bar codes, transmitting the information to the host processing device through an interconnect cable using a host specific input/output interface protocol. The UIDA contains circuitry to support numerous different host interface protocols, such as RS-232C, IBM46XX, or Keyboard Wedge interface, in order to allow a single data reader to operate with a wide variety of host processing devices. The desired host interface for the data reader is communicated to the device through any one of various methods, such as by signals initiated from the interconnect cable itself or by scanning the information from a configuration bar code. The UIDA then selects the appropriate host interface protocol and configures the scanner for operation with the host processing device.