Renesas SH7641 - Manual (Page 531)

Section 16 I 2 C Bus Interface 2 (IIC2)
Rev. 4.00 Sep. 14, 2005 Page 481 of 982
REJ09B0023-0400
Bit Bit Name
Initial
Value R/W
Description
5, 4  All 1  Reserved
These bits are always read as 1.
3 BCWP 1 R/W BC Write Protect
This bit controls the BC2 to BC0 modifications. When
modifying BC2 to BC0, this bit should be cleared to 0.
In clock synchronous serial mode, BC should not be
modified.
0: When writing, values of BC2 to BC0 are set.
1: When reading, 1 is always read.
When writing, settings of BC2 to BC0 are invalid.
Bit Counter 2 to 0
These bits specify the number of bits to be transferred
next. When read, the remaining number of transfer bits
is indicated. With the I
2 C bus format, the data is
transferred with one addition acknowledge bit. should
be made between transfer frames. If bits BC2 to BC0
are set to a value other than 000, the setting should be
made while the SCL pin is low. The value returns to 000
at the end of a data transfer, including the acknowledge
bit. These bits are cleared by a power-on reset and in
standby mode. These bits are also cleared by setting
IICRST of ICCR2 to 1. With the clock synchronous
serial format, these bits should not be modified.
2
1
0
BC2
BC1
BC0
0
0
0
R/W
R/W
R/W
I 2 C Bus Format
000: 9 bits
001: 2 bits
010: 3 bits
011: 4 bits
100: 5 bits
101: 6 bits
110: 7 bits
111: 8 bits
Clock Synchronous Serial Format
000: 8 bits
001: 1 bit
010: 2 bits
011: 3 bits
100: 4 bits
101: 5 bits
110: 6 bits
111: 7 bits