LAPIS Semiconductor ML610421, Руководство пользователя, Страница: 222 / 437

ML610Q421/ML610Q422/ML610421 User’s Manual
Chapter 15 I
2
C Bus Interface
15 – 6
15.2.5 I
2
C Bus 0 Control Register (I2C0CON)
Address: 0F2A3H
Access: R/W
Access size: 8 bits
Initial value: 00H
7 6 5 4 3 2 1 0
I2C0CON I20ACT — — — — I20RS I20SP I20ST
R/W R/W R/W R/W R/W R/W W W R/W
Initial value 0 0 0 0 0 0 0 0
I2C0CON is a special function register (SFR) to control transmit and receive operations.
[Description of Bits]
•
I20ST (bit 0)
The I20ST bit is used to control the communication operation of the I
2
C bus interface. When the I20ST bit is set to
“1”, communication starts. When “1” is overwritten to the I20ST bit in a control register setting wait state after
transmission/reception of acknowledgment, communication starts again. When the I20ST bit is set to “0”,
communication is stopped forcibly.
The I20ST bit can be set to “1” only when the I2C bus interface is in an operation enable state (I20EN = “1”).
When the I20SP bit is set to “1”, the I20ST bit is set to “0”.
I20ST Description
0 Stops communication (initial value)
1 Starts communication
•
I20SP (bit 1)
The I20SP bit is a write-only bit used to request a stop condition. When the I20SP bit is set to “1”, the I
2
C bus
shifts to the stop condition and communication stops. When the I20SP bit is read, “0” is always read.
I20SP Description
0 No stop condition request (initial value)
1 Stop condition request
•
I20RS (bit 2)
The I20RS bit is a write-only bit used to request a repeated start. When this bit is set to “1” during data
communication, the I
2
C bus shifts to the repeated start condition and communication restarts from the slave address.
I20RS can be set to “1” only while communication is active (I20ST =“1”). When the I20RS bit is read, “0” is
always read.
I20RS Description
0 No repeated start request (initial value)
1 Repeated start request
•
I20ACT (bit 7)
The I20ACT bit is used to set the acknowledge signal to be output at completion of reception.
I20ACT Description
0 Acknowledgment data “0” (initial value)
1 Acknowledgment data “1”