MC68HC908GT16 Datasheet, PDF (254/412 Pages) Motorola, Inc – Microcontrollers

Enhanced Serial Communications Interface (ESCI)
18.4 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 18-1 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 18-1. Pin Name Conventions
Generic Pin Names
Full Pin Names
RxD
PTE1/RxD
TxD
PTE0/TxD
18.5 Functional Description
Figure 18-1 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 18-2.
Technical Data
254
MC68HC908GT16 • MC68HC908GT8 — Rev. 2
Enhanced Serial Communications Interface (ESCI) Module
MOTOROLA