LH79524/LH79525 User’s Guide
I
2
C Module
Version 1.0
9-7
9.2.2 Register Definitions
9.2.2.1 I
2
C Configuration Register (ICCON)
The ICCON register allows controlling the operating mode of the I
2
C Module, operating
parameters, and contains the flags used to start a transfer and to set the data direction.
Not all bits are active in every operating mode. Check the individual bit description to
determine if the bit is active during a particular operating mode.
Table 9-4. ICCON Register
BIT
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
FIELD
///
RESET
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
TYPE
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
BIT
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
FIELD
///
SABT
RW
C
STOP
START
S
PEED
I2C
E
N
MODE
RESET
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
TYPE
RO
RO
RO
RO
RO
RO
RO
RO
RW
RW
RW
RW
RW
RW
RW
RW
ADDR
0xFF 0x00
Table 9-5. ICCON Fields
BITS
NAME
DESCRIPTION
31:8
///
Reserved
Reading returns 0. Write the reset value.
7
SABT
Stop After Bus Transaction
This bit is only active when in Master mode and
the ACK signal is not driven LOW by the Slave with which the I
2
C Module is
communicating.
Under those conditions, this bit is used to define whether or not a STOP Condi-
tion is generated after each bus transaction or not.
1 = No STOP Condition is generated
0 = An I
2
C STOP Condition is generated after each bus transaction
6
RWC
Read/Write Control
Only active in Master mode, it specifies direction for data
transfers.
1 = Read (Master receiver)
0 = Write (Master transmitter)
5
STOP
Stop Transfer
This bit is only active when in Master mode. It instructs the I
2
C
Module to terminate the data transfer after the completion of the current transac-
tion. Once the transaction is terminated, this bit is automatically reset to 0.
1 = Terminate data transfer following current transaction completion
0 = Do not terminate data transfer if additional data is pending
4
START
Start Transfer
This bit is active in both Master and Slave modes. In Master
mode, this bit causes the I
2
C Module to commence a transaction on the I
2
C bus.
In Slave mode this bit causes the I
2
C Module to transmit a byte of data to the
Master. This bit is automatically reset to 0 at the completion of the transaction.
1 = (Master) Commence transaction; (Slave) transmit one data byte
0 = No action