CHAPTER 10 SERIAL INTERFACE FUNCTION
User’s Manual U13850EJ4V0UM
265
(3) IIC clock selection registers 0, 1 (IICCL0, IICCL1)
IICCLn is used to set the transfer clock for the I
2
Cn bus.
IICCLn can be set by an 8-/1-bit memory manipulation instruction. Bits SMCn, CLn1 and CLn0 are set using
CLXn bit of IIC function expansion register n (IICXn) in combination with bits IICCEn1 and IICCEn0 of IIC clock
expansion register n (IICCEn) (n = 0, 1) (see
10.3.2 (6) I
2
Cn transfer clock setting method
).
RESET input clears IICCLn to 00H.
Figure 10-11. IIC Clock Selection Register n (IICCLn)
After reset: 00H
R/W
Note
Address: FFFFF344H, FFFFF354H
7
6
<5>
<4>
3
2
1
0
IICCLn
0
0
CLDn
DADn
SMCn
DFCn
CLn1
CLn0
(n = 0, 1)
CLDn
Detection of SCLn line level (valid only when IICEn = 1)
0
SCLn line was detected at low level.
1
SCLn line was detected at high level.
Condition for clearing (CLDn = 0)
Condition for setting (CLDn = 1)
•
When the SCLn line is at low level
•
When IICEn = 0
•
When RESET is input
•
When the SCLn line is at high level
DADn
Detection of SDAn line level (valid only when IICEn = 1)
0
SDAn line was detected at low level.
1
SDAn line was detected at high level.
Condition for clearing (DADn = 0)
Condition for setting (DADn = 1)
•
When the SDAn line is at low level
•
When IICEn = 0
•
When RESET is input
•
When the SDAn line is at high level
SMCn
Operation mode switching
0
Operates in standard mode.
1
Operates in high-speed mode.
DFCn
Digital filter operation control
0
Digital filter off.
1
Digital filter on.
Digital filter can be used only in high-speed mode.
In high-speed mode, the transfer clock does not vary regardless of DFCn switching (on/off).
Note
Bits 4 and 5 are read only bits.
Remark
IICEn: Bit 7 of IIC control register n (IICCn)