HD6432633 Datasheet, PDF (832/1453 Pages) Renesas Technology Corp – Series of Microcomputers (MCUs: microcomputer units)

17.2.4 Serial Control Register (SCR)
Bit
:
7
6
5
TIE
RIE
TE
Initial value :
0
0
0
R/W
: R/W
R/W
R/W
4
3
2
1
0
RE
MPIE TEIE CKE1 CKE0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
In smart card interface mode, the function of bits 1 and 0 of SCR changes when bit 7 of the serial
mode register (SMR) is set to 1.
Bits 7 to 2—Operate in the same way as for the normal SCI.
For details, see section 16.2.6, Serial Control Register (SCR).
Bits 1 and 0—Clock Enable 1 and 0 (CKE1, CKE0): These bits are used to select the SCI clock
source and enable or disable clock output from the SCK pin.
In smart card interface mode, in addition to the normal switching between clock output enabling
and disabling, the clock output can be specified as to be fixed high or low.
SCMR
SMIF
0
1
1
1
SMR
SCR Setting
C/A, GM CKE1
CKE0
See the SCI
0
0
0
0
0
1
1
0
0
1
1
0
1
1
1
1
0
1
1
1
1
SCK Pin Function
Operates as port I/O pin
Outputs clock as SCK output pin
Operates as SCK output pin, with output fixed
low
Outputs clock as SCK output pin
Operates as SCK output pin, with output fixed
high
Outputs clock as SCK output pin
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