
CHAPTER 17 SERIAL INTERFACE IIC0
User’s Manual U17473EJ2V0UD
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(1) During address transmission/reception
Slave device operation:
Interrupt and wait timing are determined depending on the conditions described in
Notes 1 and 2 above, regardless of the WTIM0 bit.
Master device operation: Interrupt and wait timing occur at the falling edge of the ninth clock regardless of
the WTIM0 bit.
(2) During data reception
Master/slave device operation: Interrupt and wait timing are determined according to the WTIM0 bit.
(3) During data transmission
Master/slave device operation: Interrupt and wait timing are determined according to the WTIM0 bit.
(4) Wait cancellation method
The four wait cancellation methods are as follows.
Writing data to IIC shift register 0 (IIC0)
Setting bit 5 (WREL0) of IIC control register 0 (IICC0) (canceling wait)
Setting bit 1 (STT0) of IIC0 register (generating start condition)Note
Setting bit 0 (SPT0) of IIC0 register (generating stop condition)Note
Note
Master only.
When an 8-clock wait has been selected (WTIM0 = 0), the presence/absence of ACK generation must be
determined prior to wait cancellation.
(5) Stop condition detection
INTIIC0 is generated when a stop condition is detected (only when SPIE0 = 1).
17.5.9 Address match detection method
In I
2C bus mode, the master device can select a particular slave device by transmitting the corresponding slave
address.
Address match can be detected automatically by hardware. An interrupt request (INTIIC0) occurs when a local
address has been set to slave address register 0 (SVA0) and when the address set to SVA0 matches the slave
address sent by the master device, or when an extension code has been received.
17.5.10 Error detection
In I
2C bus mode, the status of the serial data bus (SDA0) during data transmission is captured by IIC shift register 0
(IIC0) of the transmitting device, so the IIC0 data prior to transmission can be compared with the transmitted IIC0 data
to enable detection of transmission errors. A transmission error is judged as having occurred when the compared
data values do not match.