RL78/G1P
CHAPTER 12 SERIAL INTERFACE IICA
R01UH0895EJ0100 Rev.1.00
481
Nov 29, 2019
Figure 12-9. Format of IICA Control Register n1 (IICCTLn1) (2/2)
CLDn
Detection of SCLAn pin level (valid only when IICEn = 1)
0
The SCLAn pin was detected at low level.
1
The SCLAn pin was detected at high level.
Condition for clearing (CLDn = 0)
Condition for setting (CLDn = 1)
When the SCLAn pin is at low level
When IICEn = 0 (operation stop)
Reset
When the SCLAn pin is at high level
DADn
Detection of SDAAn pin level (valid only when IICEn = 1)
0
The SDAAn pin was detected at low level.
1
The SDAAn pin was detected at high level.
Condition for clearing (DADn = 0)
Condition for setting (DADn = 1)
When the SDAAn pin is at low level
When IICEn = 0 (operation stop)
Reset
When the SDAAn pin is at high level
SMCn Operation
mode
switching
0
Operates in standard mode (fastest transfer rate: 100 kbps).
1
Operates in fast mode (fastest transfer rate: 400 kbps) or fast mode plus (fastest transfer rate: 1
Mbps).
DFCn
Digital filter operation control
0
Digital filter off.
1
Digital filter on.
Digital filter can be used only in fast mode and fast mode plus.
In fast mode and fast mode plus, the transfer clock does not vary, regardless of the DFCn bit being set (1) or
cleared (0).
The digital filter is used for noise elimination in fast mode and fast mode plus.
PRSn
Division of the operation clock
0 Selects
f
CLK
as operation clock.
1 Selects
f
CLK
/2 as operation clock.
Caution
The fastest operation frequency of the operation clock of the serial interface IICA is 20
MHz (Max.). If the f
CLK
exceeds 20 MHz, set the clock to f
CLK
/2 by setting the PRSn bit to
1.
Remarks 1.
IICEn: Bit 7 of IICA control register n0 (IICCTLn0)
2.
n = 0, 1