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Read ORER and FER flags in SSR
No
Read receive data in RDR
No
Read ORER and FER flags in SSR
Read receive data in RDR
No
Figure 16-12 Sample Multiprocessor Serial Reception Flowchart
634
Initialization
Start reception
Read MPIE bit in SCR
FER∨ORER= 1
No
Read RDRF flag in SSR
RDRF= 1
Yes
This station's ID?
Yes
FER∨ORER= 1
No
Read RDRF flag in SSR
RDRF= 1
Yes
All data received?
Yes
Clear RE bit in SCR to 0
<End>
[1]
SCI initialization:
[1]
The RxD pin is automatically
designated as the receive data
input pin.
[2]
ID reception cycle:
[2]
Set the MPIE bit in SCR to 1.
[3]
SCI status check, ID reception
and comparison:
Yes
Read SSR and check that the
RDRF flag is set to 1, then read
the receive data in RDR and
compare it with this station's ID.
[3]
If the data is not this station's ID,
set the MPIE bit to 1 again, and
clear the RDRF flag to 0.
If the data is this station's ID,
clear the RDRF flag to 0.
[4]
SCI status check and data
reception:
Read SSR and check that the
RDRF flag is set to 1, then read
the data in RDR.
[5]
Receive error processing and
break detection:
If a receive error occurs, read the
ORER and FER flags in SSR to
Yes
identify the error. After
performing the appropriate error
processing, ensure that the
ORER and FER flags are all
cleared to 0.
[4]
Reception cannot be resumed if
either of these flags is set to 1.
No
In the case of a framing error, a
break can be detected by reading
the RxD pin value.
[5]
Error processing
(Continued on
next page)
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