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10.1.2
Block diagram
Figure 10.1 shows a block diagram of SCI3.
Clock
TXD
RXD
SCK
BRR
SMR
SCR3
SSR
TDR
RDR
TSR
RSR
SPCR
Transmit/receive
control circuit
Internal data bus
Notation:
RSR:
RDR:
TSR:
TDR:
SMR:
SCR3:
SSR:
BRR:
BRC:
SPCR:
Receive shift register
Receive data register
Transmit shift register
Transmit data register
Serial mode register
Serial control register 3
Serial status register
Bit rate register
Bit rate counter
Serial port control register
Interrupt request
(TEI, TXI, RXI, ERI)
3x
Internal clock (ø/64, ø/16, øw/2, ø)
External
clock
BRC
Baud rate generator
Figure 10.1 SCI3 Block Diagram