Figure 15.16 shows an example of SCI operation for multiprocessor format reception.
Data
(Data1)
Start
bit
Stop Start
bit bit
Stop
bit
1
MPB
1
1
MPB
0
Data (ID1)
D0 D1
Serial
data
Idle state
(mark state)
0
D7
1
0
D0 D1
D7
1
MPIE
RDRF
SCRDR1
value
ID1
RXI interrupt request SCRDR1 data read As data is not this RXI interrupt The RDRF flag
(multiprocessor
interrupt)
MPIE = 0
and RDRF flag
cleared to 0 by RXI
interrupt handler
station’s ID, MPIE request
bit is set to 1 again
is cleared to 0
by the RXI
interrupt handler.
(a) Data does not match station’s ID
Data
(Data2)
Start
bit
Stop Start
bit bit
Stop
bit
MPB
1
MPB
0
1
1
Data (ID2)
Idle state
(mark state)
Serial
data
0
D0
D1
D7
1
0
D0 D1
D7
1
MPIE
RDRF
SCRDR1
value
Data2
ID2
ID1
RXI interrupt request
(multiprocessor interrupt)
MPIE = 0
As data matches this
MPIE bit set
to 1 again
SCRDR1 data read
and RDRF flag
cleared to 0 by RXI
interrupt handler
station’s ID, reception
continues and data is
received by RXI
interrupt handler
(b) Data matches station’s ID
Figure 15.16 Example of SCI Receive Operation (Example with 8-Bit Data, Multiprocessor
Bit, One Stop Bit)
Rev. 6.0, 07/02, page 641 of 986
RENESAS [ RENESAS TECHNOLOGY CORP ]
