MC68HC908GZ8 Datasheet, PDF (220/344 Pages) Motorola, Inc – Microcontrollers

Enhanced Serial Communications Interface (ESCI) Module
• 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
19.3 Pin Name Conventions
The generic names of the ESCI input/output (I/O) pins are:
• RxD (receive data)
• TxD (transmit data)
ESCI I/O lines are implemented by sharing parallel I/O port pins. The full name of
an ESCI input or output reflects the name of the shared port pin. Table 19-1 shows
the full names and the generic names of the ESCI I/O pins. The generic pin names
appear in the text of this section.
Table 19-1. Pin Name Conventions
Generic Pin Names
Full Pin Names
RxD
PTE1/RxD
TxD
PTE0/TxD
19.4 Functional Description
Figure 19-1 shows the structure of the ESCI module. The ESCI allows full-duplex,
asynchronous, NRZ serial communication between the MCU and remote devices,
including other MCUs. The transmitter and receiver of the ESCI operate
independently, although they use the same baud rate generator. During normal
operation, the CPU monitors the status of the ESCI, writes the data to be
transmitted, and processes received data.
For reference, a summary of the ESCI module input/output registers is provided in
Figure 19-2.
Data Sheet
220
Enhanced Serial Communications Interface (ESCI) Module
MC68HC908GZ8
Freescale Semiconductor