Serial Communications Interface (SCI)
Pin Name Conventions
MC68HC908AZ60A — Rev 2.0 Technical Data
MOTOROLA Serial Communications Interface (SCI) 245
– Idle Receiver Input
– Receiver Overrun
– Noise Error
– Framing Error
– Parity Error
• Receiver Framing Error Detection
• Hardware Parity Checking
• 1/16 Bit-Time Noise Detection
18.4 Pin Name Conventions
The generic names of the SCI input/output (I/O) pins are:
• RxD (receive data)
• TxD (transmit data)
SCI I/O lines are implemented by sharing parallel I/O port pins. The full
name of an SCI input or output reflects the name of the shared port pin.
Table 18-1 shows the full names and the generic names of the SCI I/O
pins.The generic pin names appear in the text of this section.
18.5 Functional Description
Figure 18-1 shows the structure of the SCI module. The SCI allows full-
duplex, asynchronous, NRZ serial communication between the MCU
and remote devices, including other MCUs. The transmitter and receiver
of the SCI operate independently, although they use the same baud rate
generator. During normal operation, the CPU monitors the status of the
SCI, writes the data to be transmitted, and processes received data.
Table 18-1. Pin Name Conventions
Generic Pin Names RxD TxD
Full Pin Names PTE1/SCRxD PTE0/SCTxD
