NEC 78K0 Series User Manual page 467

(f) When arbitration loss occurs due to low-level data when attempting to generate a restart condition
(i) When WTIM0 = 0
ST AD6 to AD0 R/W ACK
1: IICS0 = 1000×110B
2: IICS0 = 1000×000B (Sets WTIM0 to 1)
3: IICS0 = 1000×100B (Clears WTIM0 to 0)
4: IICS0 = 01000000B
5: IICS0 = 00000001B
Remark : Always generated
: Generated only when SPIE0 = 1
×: Don't care
(ii) When WTIM0 = 1
ST AD6 to AD0 R/W ACK
1: IICS0 = 1000×110B
2: IICS0 = 1000×100B (Sets STT0 to 1)
3: IICS0 = 01000100B
4: IICS0 = 00000001B
Remark : Always generated
: Generated only when SPIE0 = 1
×: Don't care
CHAPTER 17 SERIAL INTERFACE IIC0
STT0 = 1
↓
D7 to D0 ACK D7 to D0
1 2 3
STT0 = 1
↓
D7 to D0 ACK D7 to D0
1 2
Preliminary User's Manual U17260EJ3V1UD
ACK D7 to D0 ACK SP
4
ACK D7 to D0 ACK SP
3
5
4
467