Host Address Detection - Renesas RZ/A Series User Manual

RZ/A1L Group, RZ/A1LU Group, RZ/A1LC Group
18.9.4

Host Address Detection

The RIIC has a function to detect the host address while the SMBus is operating. When the
RIICnSER.HOAE bit is set to 1 while the RIICnMR3.SMBS bit is 1, the RIIC can detect the host
address (0001 000
When the RIIC detects the host address, the RIICnSR1.HOA flag is set to 1 at the rising edge of the
ninth SCL clock cycle, and at the same time, the RIICnSR2.RDRF flag is set to 1 when the R/W# bit is
0 (Wr bit). This causes a receive data full interrupt (INTRIICRI) to be generated. The HOA flag is used
to recognize that the host address was sent from the smart battery or other devices.
If the bit following the host address (0001 000
the host address. After the host address is detected, the RIIC operates in the same manner as normal
slave operation.
[Host address reception]
SCLn
SDAn
BBSY
AAS0
AAS1
AAS2
HOA
RDRF
Figure 18.29
R01UH0437EJ0600 Rev.6.00
Jan 29, 2021
) in slave receive mode (RIICnCR2.MST and TRS bits = 00
B
S 1 2 3 4 5 6
0 0 0 1 0 0
HOA Flag Set Timing during Reception of Host Address
) is an Rd bit (R/W# bit = 1), the RIIC can also detect
B
7 8 9 1 2 3 4
Data (DATA 1)
0 W ACK
Receive data (7-bit address)
Host address match (0001 000b)
Read RIICnDRR
(Dummy read [7-bit address])
18. I²C Bus Interface
).
B
5 6 7 8 9 1 2
ACK
Receive data (DATA 1)
Read RIICnDRR
(DATA 1)
3 4 5
Data (DATA 2)
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