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UART Serial Data

Description
Two methods of data transmission are used. One method involves a Universally Asynchronous Receiving/Transmitting (UART) protocol. UART is an interfacing device that allows the on board computer to send and receive serial data. Serial data refers to information which is transferred in a linear fashion - over a single line, one bit at a time. A data bus describes the electronic pathway through which serial data travels.

Operation
The UART receives data in a serial format, converts the data to parallel format, and places them on the data bus (which is recognizable to the on board computer). This method had been the common strategy for establishing a communication link between the on board control module and the off board monitor/scanner since 1981. UART is now used to communicate between certain modules within the vehicle.