SH7760 Datasheet, PDF (643/1345 Pages) Renesas Technology Corp – SuperHTM RISC engine

(5) Serial Data Reception (Synchronous Mode)
Figure 17.19 shows a sample flowchart for serial reception.
Use the following procedure for serial data reception after enabling the SCIF for reception.
When switching the operating mode from asynchronous mode to synchronous mode without
initializing the SCIF, make sure that the ORER, PER7 to PER0, and FER7 to FER0 flags are
cleared to 0.
Initialization
[1]
Start of reception
[1] SCIF initialization:
See Sample SCIF Initialization
Flowchart in figure 17.16.
[2] Receive error handling:
Read ORER flag in SCLSR
ORER = 1?
No
Yes
[2]
Error handling
Read the ORER flag in SCLSR to
identify any error, perform the
appropriate error handling, then clear
the ORER flag to 0.
Transmission/reception cannot be
resumed while the ORER flag is set
to 1.
[3] SCIF status check and receive data
read:
Read RDF flag in SCFSR
[3]
No
RDF = 1?
Yes
Read receive data in
SCFRDR, and clear RDF
[4]
flag in SCFSR to 0
No
All data received?
Yes
Read SCFSR and check that RDF =
1, then read the receive data in
SCFRDR, and clear the RDF flag to
0. The transition of the RDF flag from
0 to 1 can also be identified by an
RXI interrupt.
[4] Serial reception continuation
procedure:
To continue serial reception, read at
least the receive trigger set number
of receive data bytes from SCFRDR,
read 1 from the RDF flag, then clear
the RDF flag to 0. The number of
receive data bytes in SCFRDR can
be ascertained by reading SCRFDR.
Clear RE bit in SCSCR to 0
End of reception
Figure 17.19 Sample Serial Reception Flowchart (1)
Rev. 1.0, 02/03, page 593 of 1294