Datasheet

Section 15 Serial Communication Interface (SCI, IrDA)
Page 910 of 1408 R01UH0309EJ0500 Rev. 5.00
Sep 24, 2012
H8S/2456, H8S/2456R, H8S/2454 Group
Yes
<End>
[1]
No
Initialization
Start of reception
No
Yes
[4]
Clear RE bit in SCR to 0
Error handling
(Continued on
next page)
[5]
No
Yes
FER ∨ ORER = 1?
RDRF = 1?
All data received?
Set MPIE bit in SCR to 1 [2]
Read ORER and FER flags in SSR
Read RDRF flag in SSR [3]
Read receive data in RDR
No
Yes
This station's ID?
Read ORER and FER flags in SSR
Yes
No
Read RDRF flag in SSR
No
Yes
FER ∨ ORER = 1?
Read receive data in RDR
RDRF = 1?
SCI initialization:
The RxD pin is automatically
designated as the receive data
input pin.
ID reception cycle:
Set the MPIE bit in SCR to 1.
SCI status check, ID reception
and comparison:
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.
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.
SCI status check and data
reception:
Read SSR and check that the
RDRF flag is set to 1, then read
the data in RDR.
Receive error handling 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
handling, ensure that the ORER
and FER flags are both 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.
[1]
[2]
[3]
[4]
[5]
Figure 15.13 Sample Multiprocessor Serial Reception Flowchart (1)