Bit 3—Acknowledgement Mode Select (ACK): Selects acknowledgement mode or serial mode.
In acknowledgement mode (ACK = 0), data is transferred in frames consisting of the number of
data bits selected by BC2 to BC0 in ICMR, plus an extra acknowledge bit. In serial mode (ACK =
1), the number of data bits selected by BC2 to BC0 in ICMR is transferred as one frame.
Bit 3: ACK
Description
0
1
Acknowledgement mode
Serial mode
(Initial value)
Bits 2 to 0—Serial Clock Select (CKS2 to CKS0): These bits, together with the IICX bit in the
STCR register, select the serial clock frequency in master mode. They should be set according to
the required transfer rate.
Transfer Rate*
(STCR) Bit 2: Bit 1: Bit 0:
IICX
CKS2 CKS1 CKS0 Clock øP = 5 MHz øP = 8 MHz øP = 10 MHz øP = 16 MHz
0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
øP/28
øP/40
øP/48
øP/64
øP/80
179 kHz
125 kHz
104 kHz
78.1 kHz
62.5 kHz
286 kHz
200 kHz
167 kHz
125 kHz
100 kHz
80.0 kHz
71.4 kHz
62.5 kHz
143 kHz
100 kHz
83.3 kHz
62.5 kHz
50.0 kHz
40.0 kHz
35.7 kHz
31.3 kHz
357 kHz
250 kHz
208 kHz
156 kHz
125 kHz
100 kHz
89.3 kHz
78.1 kHz
179 kHz
125 kHz
104 kHz
78.1 kHz
62.5 kHz
50.0 kHz
44.6 kHz
39.1 kHz
571 kHz
400 kHz
333 kHz
250 kHz
200 kHz
160 kHz
143 kHz
125 kHz
286 kHz
200 kHz
167 kHz
125 kHz
100 kHz
80.0 kHz
71.4 kHz
62.5 kHz
øP/100 50.0 kHz
øP/112 44.6 kHz
øP/128 39.1 kHz
1
øP/56
øP/80
øP/96
89.3 kHz
62.5 kHz
52.1 kHz
øP/128 39.1 kHz
øP/160 31.3 kHz
øP/200 25.0 kHz
øP/224 22.3 kHz
øP/256 19.5 kHz
Note: * øP = ø.
The shaded setting exceeds the maximum transfer rate in the standard I2C bus
specifications.
289
RENESAS [ RENESAS TECHNOLOGY CORP ]
