MC908JL8CDWE Datasheet, PDF (121/212 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 9
Serial Communications Interface (SCI)
9.1 Introduction
This section describes the serial communications interface (SCI) module, which allows high-speed
asynchronous communications with peripheral devices and other MCUs.
9.2 Features
Features of the SCI module include the following:
• Full-duplex operation
• Standard mark/space non-return-to-zero (NRZ) format
• 32 programmable baud rates
• Programmable 8-bit or 9-bit character length
• Separately enabled transmitter and receiver
• Separate receiver and transmitter 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
• Bus clock as baud rate clock source
9.3 Pin Name Conventions
The generic names of the SCI I/O pins are:
• RxD (receive data)
• TxD (transmit data)
The SCI I/O (input/output) lines are dedicated pins for the SCI module. Table 9-1 shows the full names
and the generic names of the SCI I/O pins.
MC68HC908JL8/JK8 • MC68HC08JL8/JK8 • MC68HC908KL8 Data Sheet, Rev. 3.1
Freescale Semiconductor
121