Datasheet

78K0/Ix2 CHAPTER 15 SERIAL INTERFACE IICA
R01UH0010EJ0500 Rev.5.00 511
Feb 28, 2012
(2) When communication reservation function is disabled (bit 0 (IICRSV) of IICA flag register 0 (IICAF0) = 1)
When bit 1 (STT0) of the IICA control register 0 (IICACTL0) is set to 1 when the bus is not used in a communication
during bus communication, this request is rejected and a start condition is not generated. The following two
statuses are included in the status where bus is not used.
 When arbitration results in neither master nor slave operation
 When an extension code is received and slave operation is disabled (ACK is not returned and the bus was
released by setting bit 6 (LREL0) of the IICACTL0 register to 1 and saving communication)
To confirm whether the start condition was generated or request was rejected, check the STCF flag (bit 7 of IICF0
register). It takes up to 5 clocks until the STCF flag is set to 1 after setting STT0 = 1. Therefore, secure the time
by software.