CHAPTER 16 I
2
C BUS
User’s Manual U16896EJ2V0UD
484
16.5.7 Wait state cancellation method
In the case of I
2
C0, wait state can be canceled normally in the following ways.
•
By writing data to the IIC0 register
•
By setting the IICC0.WREL0 bit (wait state cancellation)
•
By setting the IICC0.STT0 bit (start condition generation)
Note
•
By setting the IICC0.SPT0 bit (stop condition generation)
Note
Note
Master
only
If any of these wait state cancellation actions is performed, I
2
C0 will cancel wait state and restart communication.
When canceling wait state and sending data (including address), write data to the IIC0 register.
To receive data after canceling wait state, or to complete data transmission, set the WREL0 bit to 1.
To generate a restart condition after canceling wait state, set the STT0 bit to 1.
To generate a stop condition after canceling wait state, set the SPT0 bit to 1.
Execute cancellation only once for each wait state.
For example, if data is written to the IIC0 register following wait state cancellation by setting the WREL0 bit to 1,
conflict between the SDA0 line change timing and IIC0 register write timing may result in the data output to the SDA0
line may be incorrect.
Even in other operations, if communication is stopped halfway, clearing the IICC0.IICE0 bit to 0 will stop
communication, enabling wait state to be cancelled.
If the I
2
C bus dead-locks due to noise, etc., setting the IICC0.LREL0 bit to 1 causes the communication operation to
be exited, enabling wait state to be cancelled.
<R>
Содержание V850ES/KE1+
Страница 2: ...User s Manual U16896EJ2V0UD 2 MEMO...