Figure 12.13 Sample Multiprocessor Serial Reception Flowchart (1) - Renesas H8S/2111B Hardware Manual

Set MPIE bit in SCR to 1
Read ORER and FER flags in SSR
FER ∨ ORER = 1
Read RDRF flag in SSR
No
Read receive data in RDR
No
This station's ID?
Read ORER and FER flags in SSR
FER ∨ ORER = 1
Read RDRF flag in SSR
Read receive data in RDR
No
All data received?
Clear RE bit in SCR to 0

Figure 12.13 Sample Multiprocessor Serial Reception Flowchart (1)

Rev. 1.00, 05/04, page 262 of 544
Initialization
Start reception
No
RDRF = 1
Yes
Yes
Yes
No
RDRF = 1
Yes
Yes
<End>
[1] SCI initialization:
[1]
The RxD pin is automatically designated as
the receive data input pin.
[2] ID reception cycle:
Set the MPIE bit in SCR to 1.
[2]
[3] SCI status check, ID reception and
comparison:
Read SSR and check that the RDRF flag is
Yes
set to 1, then read the receive data in RDR
and compare it with this station's ID.
If the data is not this station's ID, set the MPIE
bit to 1 again, and clear the RDRF flag to 0.
[3] 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 identify the error. After
performing the appropriate error processing,
ensure that the ORER and FER flags are all
cleared to 0.
Reception cannot be resumed if either of
these flags is set to 1.
In the case of a framing error, a break can be
detected by reading the RxD pin value.
[Legend]
∨ : Logical OR
[4]
No
[5]
Error processing
(Continued on
next page)