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MC9S08GB/GT Data Sheet, Rev. 2.3
Freescale Semiconductor
167
Chapter 11 Serial Communications Interface (SCI) Module
11.1
Introduction
The MC9S08GB/GT includes two independent serial communications interface (SCI) modules —
sometimescalleduniversalasynchronousreceiver/transmitters(UARTs).Typically,thesesystemsareused
to connect to the RS232 serial input/output (I/O) port of a personal computer or workstation, and they can
also be used to communicate with other embedded controllers.
A flexible, 13-bit, modulo-basedbaud rate generatorsupports a broad rangeof standard baud rates beyond
115.2 kbaud. Transmit and receive within the same SCI use a common baud rate, and each SCI module
has a separate baud rate generator.
This SCI system offers many advanced features not commonly found on other asynchronous serial I/O
peripherals on other embedded controllers. The receiver employs an advanced data sampling technique
that ensures reliable communication and noise detection. Hardware parity, receiver wakeup, and double
buffering on transmit and receive are also included.