RL78/F13, F14 CHAPTER 16 SERIAL INTERFACE IICA
R01UH0368EJ0210 Rev.2.10 1093
Dec 10, 2015
The meanings of <7> to <15> in (3) Data ~ data ~ stop condition in Figure 16-32 are explained below.
<7> After data transfer is completed, because of ACKE0 = 1, the slave device sends an ACK by hardware to the
master device. The ACK is detected by the master device (ACKD0 = 1) at the rising edge of the 9th clock.
<8> The master device and slave device set a wait status (SCLA0 = 0) at the falling edge of the 9th clock, and
both the master device and slave device issue an interrupt (INTIICA0: end of transfer).
<9> The master device writes the data to transmit to the IICA shift register 0 (IICA0) and releases the wait status
that it set by the master device.
<10> The slave device reads the received data and releases the wait status (WREL0 = 1). The master device then
starts transferring data to the slave device.
<11> When data transfer is complete, the slave device (ACKE0 =1) sends an ACK by hardware to the master
device. The ACK is detected by the master device (ACKD0 = 1) at the rising edge of the 9th clock.
<12> The master device and slave device set a wait status (SCLA0 = 0) at the falling edge of the 9th clock, and
both the master device and slave device issue an interrupt (INTIICA0: end of transfer).
<13> The slave device reads the received data and releases the wait status (WREL0 = 1).
<14> By the master device setting a stop condition trigger (SPT0 = 1), the bus data line is cleared (SDAA0 = 0)
and the bus clock line is set (SCLA0 = 1). After the stop condition setup time has elapsed, by setting the bus
data line (SDAA0 = 1), the stop condition is then generated (i.e. SCLA0 =1 changes SDAA0 from 0 to 1).
<15> When a stop condition is generated, the slave device detects the stop condition and issues an interrupt
(INTIICA0: stop condition).
Remark <1> to <15> in Figure 16-32 represent the entire procedure for communicating data using the I
2
C bus.
Figure 16-32 (1) Start condition ~ address ~ data shows the processing from <1> to <6>, Figure 16-32 (2)
Address ~ data ~ data shows the processing from <3> to <10>, and Figure 16-32 (3) Data ~ data ~ stop
condition shows the processing from <7> to <15>.