Hitachi H8/3032 Series Hardware Manual page 370

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Figure 11-13 shows an example of SCI receive operation using a multiprocessor format.
Start
Data (ID1)
1
bit
0 D0
MPIE
RDRF
RDR value
Start
1 Data (ID2)
bit
0 D0
MPIE
RDRF
RDR value ID1
Figure 11-13 Example of SCI Receive Operation (8-Bit Data with Multiprocessor Bit and
Stop Start
MPB Data (data1)
bit bit
D1 D7 1 1 0 D0
RXI request RXI handler reads
(multiprocessor RDR data and clears
interrupt), MPIE = 0 RDRF flag to 0
a. Own ID does not match data
Stop Start
MPB Data (data2)
bit bit
D1 D7 1 1 0 D0
RXI request RXI interrupt handler
(multiprocessor reads RDR data and
interrupt), MPIE = 0 clears RDRF flag to 0
b. Own ID matches data
One Stop Bit)
355
Stop
MPB
1
bit
D1 D7 0 1 Idle (mark)
state
ID1
Not own ID, so No RXI request,
MPIE bit is set RDR not updated
to 1 again
Stop
MPB 1
bit
D1 D7 0 1 Idle (mark)
state
ID2 Data 2
Own ID, so receiving MPIE bit is set
continues, with data to 1 again
received by RXI
interrupt handler