RL78/G1P
CHAPTER 12 SERIAL INTERFACE IICA
R01UH0895EJ0100 Rev.1.00
542
Nov 29, 2019
The following describes the operations in Figure 12-32 (4) Data ~ restart condition ~ address. After the operations
in steps <7> and <8>, the operations in steps <i> to <iii> are performed. These steps return the processing to step
<iii>, the data transmission step.
<7> After data transfer is completed, because of ACKEn = 1, the slave device sends an ACK by hardware to the
master device. The ACK is detected by the master device (ACKDn = 1) at the rising edge of the 9th clock.
<8> The master device and slave device set a wait status (SCLAn = 0) at the falling edge of the 9th clock, and
both the master device and slave device issue an interrupt (INTIICAn: end of transfer).
<i>
The slave device reads the received data and releases the wait status (WRELn = 1).
<ii> The start condition trigger is set again by the master device (STTn = 1) and a start condition (i.e. SCLAn =1
changes SDAAn from 1 to 0) is generated once the bus clock line goes high (SCLAn = 1) and the bus data
line goes low (SDAAn = 0) after the restart condition setup time has elapsed. When the start condition is
subsequently detected, the master device is ready to communicate once the bus clock line goes low
(SCLAn = 0) after the hold time has elapsed.
<iii> The master device writing the a R/W (transmission) to the IICA shift register (IICAn) enables the
slave address to be transmitted.
Remark
n = 0, 1