MC68HC908AP64_07 FREESCALE [Freescale Semiconductor, Inc], MC68HC908AP64_07 Datasheet - Page 157

• Manufacturer Part Number: MC68HC908AP64_07
• Description: Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

11.4 Functional Description
Figure 11-2
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 ($001D).
Freescale Semiconductor
BUS CLOCK
CGMXCLK
CGMXCLK is from CGM module
RxD
shows the structure of the SCI module. The SCI allows full-duplex, asynchronous, NRZ serial
SL = 0 => X = A
SL = 1 => X = B
SCTIE
SCRIE
RWU
TCIE
SCIBDSRC
SBK
ILIE
RE
TE
CONFIG
A
B
FROM
SL
SHIFT REGISTER
X
REGISTER
SCI DATA
RECEIVE
÷ 4
CONTROL
WAKEUP
Figure 11-2. SCI Module Block Diagram
SCRF
SCTE
IDLE
SCALER
MC68HC908AP Family Data Sheet, Rev. 4
TC
ENSCI
PRE-
DIVIDER
BAUD
÷ 16
CONTROL
RECEIVE
INTERNAL BUS
LOOPS
BKF
RPF
DATA SELECTION
CONTROL
OR
NF
FE
PE
FLAG
CONTROL
WAKE
ILTY
PEN
PTY
LOOPS
ENSCI
M
TRANSMIT
CONTROL
SHIFT REGISTER
DMARE
DMATE
Functional Description
TXINV
ORIE
NEIE
FEIE
PEIE
R8
T8
REGISTER
TRANSMIT
SCI DATA
TxD
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