Datasheet

MC68HC908KX8 • MC68HC908KX2 • MC68HC08KX8 Data Sheet, Rev. 2.1
Freescale Semiconductor 111
Chapter 12
Serial Communications Interface Module (SCI)
12.1 Introduction
The serial communications interface (SCI) allows asynchronous communications with peripheral devices
and other microcontroller unit (MCU).
12.2 Features
The SCI module’s features include:
• Full-duplex operation
• Standard mark/space non-return-to-zero (NRZ) format
• Choice of baud rate clock source:
– Internal bus clock
–CGMXCLK
• 32 programmable baud rates
• Programmable 8-bit or 9-bit character length
• Separately enabled transmitter and receiver
• Separate receiver and transmitter central processor unit (CPU) interrupt requests
• Programmable transmitter output polarity
• Two receiver wakeup methods:
– Idle line wakeup
– Address mark wakeup
• Interrupt-driven operation with eight interrupt flags:
– Transmitter empty
– Transmission complete
– Receiver full
– Idle receiver input
– Receiver overrun
– Noise error
– Framing error
– Parity error
• Receiver framing error detection
• Hardware parity checking
• 1/16 bit-time noise detection