HD6475328-CP10 Datasheet, PDF (262/459 Pages) Hitachi Semiconductor – original Hitachi CMOS microcomputer unit (MCU)

14.1.3 Input and Output Pins
Table 14-1 lists the input and output pins used by the SCI module.
Table 14-1 SCI Input/Output Pins
Name
Serial clock
Receive data
Transmit data
Abbreviation
SCK
RXD
TXD
I/O
Input/output
Input
Output
Function
Serial clock input and output.
Receive data input.
Transmit data output.
14.1.4 Register Configuration
Table 14-2 lists the SCI registers.
Table 14-2 SCI Registers
Name
Abbreviation R/W
Initial Value Address
Receive shift register
RSR
—
—
—
Receive data register
RDR
R
H'00
H'FFDD
Transmit shift register
TSR
—
—
—
Transmit data register
TDR
R/W
H'FF
H'FFDB
Serial mode register
SMR
R/W
H'04
H'FFD8
Serial control register
SCR
R/W
H'0C
H'FFDA
Serial status register
SSR
R/(W)* H'87
H'FFDC
Bit rate register
BRR
R/W
H'FF
H'FFD9
* Software can write a “0” to clear the status flag bits, but cannot write a “1.”
14.2 Register Descriptions
14.2.1 Receive Shift Register (RSR)
Bit
7
6
5
4
3
2
1
0
Read/Write
—
—
—
—
—
—
—
—
The RSR receives incoming data bits. When one data character has been received, it is transferred
to the receive data register (RDR).
The CPU cannot read or write the RSR directly.
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