Figure 12.13 Example Of Sci Receive Operation (8-Bit Data With Multiprocessor Bit And One Stop Bit) - Hitachi H8/3062 Hardware Manual

Figure 12.13 shows an example of SCI receive operation using a multiprocessor format.
Start
1
bit
0 D0
MPIE
RDRF
RDR value
RXI interrupt request
MPB detection
(multiprocessor interrupt)
MPIE = 0
Start
1
bit
0 D0
MPIE
RDRF
ID1
RDR value
RXI interrupt request
MPB detection
(multiprocessor interrupt)
MPIE = 0
(8-Bit Data with Multiprocessor Bit and One Stop Bit)
406
Data (ID1) MPB
D7
D1
1
RXI interrupt handler reads
RDR data and clears
RDRF flag to 0
a. Own ID does not match data
Data (ID2) MPB
D7
D1
1
b. Own ID matches data
Figure 12.13 Example of SCI Receive Operation
Stop Start
Data (data1)
bit bit
0
D0 D1
1
Stop Start
Data (data2)
bit bit
0
D0 D1
1
RXI interrupt handler Own ID, so receiving
reads RDR data and continues, with data
clears RDRF flag to 0 received by RXI
interrupt handler
Stop
MPB
bit
D7 1
0
Idle (mark)
state
ID1
Not own ID, so MPIE No RXI interrupt
bit is set to 1 again request, RDR not
updated
Stop
MPB
bit
D7 1
0
Idle (mark)
state
ID2
Data2
MPIE bit is set to
1 again
1
1