mc68hc908gr8b Freescale Semiconductor, Inc, mc68hc908gr8b Datasheet - Page 131

• Manufacturer Part Number: mc68hc908gr8b
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

13.3 Pin Name Conventions
The generic names of the SCI I/O pins are:
SCI I/O (input/output) 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.
names of the SCI I/O pins.
The generic pin names appear in the text of this section.
13.4 Functional Description
Figure 13-3
communication among 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.
The baud rate clock source for the SCI can be selected via the configuration bit, SCIBDSRC, of the
CONFIG2 register ($001E). Source selection values are shown in
13.4.1 Data Format
The SCI uses the standard non-return-to-zero mark/space data format illustrated in
Freescale Semiconductor
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•
RxD (receive data)
TxD (transmit data)
shows the structure of the SCI module. The SCI allows full-duplex, asynchronous, NRZ serial
START
START
BIT
BIT
BIT 0
BIT 0
BIT 1
BIT 1
Generic Pin Names:
BIT 2
BIT 2
Table 13-1. Pin Name Conventions
MC68HC908GR8B Data Sheet, Rev. 3.0
Full Pin Names:
Figure 13-2. SCI Data Formats
BIT 3
BIT 3
BIT M IN SCC1 CLEAR
8-BIT DATA FORMAT
9-BIT DATA FORMAT
BIT M IN SCC1 SET
BIT 4
BIT 4
BIT 5
BIT 5
PTE1/RxD
Table 13-1
RxD
BIT 6
BIT 6
PARITY
BIT 7
BIT 7
BIT
Figure
shows the full names and the generic
PTE0/TxD
PARITY
STOP
BIT 8
TxD
BIT
BIT
13-3.
START
STOP
NEXT
BIT
BIT
START
NEXT
BIT
Pin Name Conventions
Figure
13-2.
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