CHAPTER 17 SERIAL INTERFACE IIC0 (
µ
PD780344Y, 780354Y SUBSERIES ONLY)
349
User’s Manual U15798EJ2V0UD
Figure 17-16. Communication Reservation Timing
2
1
3
4
5
6
2
1
3
4
5
6
7
8
9
SCL0
SDA0
Program processing
Hardware processing
Write to
IIC0
Set SPD0
and INTIIC0
STT0 = 1
Communi-
cation
reservation
Set
STD0
Output by master with bus access
Remark
IIC0:
IIC shift register 0
STT0: Bit 1 of IIC control register 0 (IICC0)
STD0: Bit 1 of IIC status register 0 (IICS0)
SPD0: Bit 0 of IIC status register 0 (IICS0)
Communication reservations are accepted at the following timing. After bit 1 (STD0) of IIC status register 0 (IICS0)
is set to 1, a communication reservation can be made by setting bit 1 (STT0) of IIC control register 0 (IICC0) to 1
before a stop condition is detected.
Figure 17-17. Timing for Accepting Communication Reservations
SCL0
SDA0
STD0
SPD0
Standby mode
Figure 17-18 shows the communication reservation protocol.
