Renesas H8 Series Hardware Manual page 415

• Receiving
Figure 10.13 shows an example of a flowchart for data reception. This procedure should be
followed for data reception after initializing SCI3.
Read bit OER
OER = 1?
Read bit RDRF
RDRF = 1?
Read receive
data in RDR
Continue data
reception?
Clear bit RE to
0 in SCR3
Figure 10.13 Example of Data Reception Flowchart (Synchronous Mode)
Start
[1]
in SSR
Yes
No
[2]
in SSR
No
Yes
Overrun error
processing
[3]
Yes
No
Start overrun
4
error processing
Overrun error
End
processing
Clear bit OER to
End of overrun
error processing
Section 10 Serial Communication Interface
[1] Read bit OER in the serial status register
(SSR) to determine if there is an error.
If an overrun error has occurred, execute
overrun error processing.
[2] Read SSR and check that bit RDRF is
set to 1. If it is, read the receive data in
RDR. When the RDR data is read, bit
RDRF is cleared to 0 automatically.
[3] When continuing data reception, finish
reading of bit RDRF and RDR before
receiving the MSB (bit 7) of the current
frame. When the data in RDR is read,
bit RDRF is cleared to 0 automatically.
[4] If an overrun error has occurred, read bit
OER in SSR, and after carrying out the
necessary error processing, clear bit OER
to 0. Reception cannot be resumed if bit
OER is set to 1.
[4]
0 in SSR
Rev. 7.00 Mar 10, 2005 page 373 of 652
REJ09B0042-0700