
R8C/10 Group 13.1 Clock Synchronous Serial I/O Mode
Rev.1.20 Jan 27, 2006 page 97 of 180
REJ09B0019-0120
13.1.1 Polarity Select Function
Figure 13.7 shows the polarity of the transfer clock. Use the CKPOL bit in the U0C0 register to select
the transfer clock polarity.
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W
h
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U
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r
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C
K
P
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b
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1
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D
0
D
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T
X
D
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R
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D
0
C
L
K
0
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C
K
P
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L
b
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D
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D
7
D
0
T
X
D
0
R
X
D
0
C
L
K
0
NOTES:
1. When not transferring, the CLK0 pin outputs a high signal.
2. When not transferring, the CLK0 pin outputs a low signal.
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Figure 13.7 Transfer Clock Polarity
13.1.2 LSB First/MSB First Select Function
Figure 13.8 shows the transfer format. Use the UFORM bit in the U0C0 register to select the transfer
format.
Figure 13.8 Transfer Format
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W
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U
0
C
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U
F
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M
b
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L
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f
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)
D
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T
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D
0
R
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D
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C
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K
0
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U
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C
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D
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N
O
T
E
S
:
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