h8s-2646 Renesas Electronics Corporation., h8s-2646 Datasheet - Page 500

• Manufacturer Part Number: h8s-2646
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 13 Serial Communication Interface (SCI)
Serial data reception (asynchronous mode): Figure 13.7 shows a sample flowchart for serial
reception.
The following procedure should be used for serial data reception.
Rev. 5.00 Sep 22, 2005 page 474 of 1136
REJ09B0257-0500
No
No
Read receive data in RDR, and
clear RDRF flag in SSR to 0
PER
Read RDRF flag in SSR
Clear RE bit in SCR to 0
Read ORER, PER, and
All data received?
FER flags in SSR
Figure 13.7 Sample Serial Reception Data Flowchart
Start reception
Initialization
FER
RDRF = 1
<End>
Yes
Yes
No
ORER = 1
(Continued on next page)
Error processing
Yes
[1]
[2]
[4]
[5]
[3]
[1]
[2] [3]
[4]
[5]
SCI initialization:
The RxD pin is automatically
designated as the receive data
input pin.
break detection:
If a receive error occurs, read the
ORER, PER, and FER flags in
SSR to identify the error. After
performing the appropriate error
processing, ensure that the
ORER, PER, and FER flags are
all cleared to 0. Reception cannot
be resumed if any of these flags
are set to 1. In the case of a
framing error, a break can be
detected by reading the value of
the input port corresponding to
the RxD pin.
SCI status check and receive
data read :
Read SSR and check that RDRF
= 1, then read the receive data in
RDR and clear the RDRF flag to
0. Transition of the RDRF flag
from 0 to 1 can also be identified
by an RXI interrupt.
Serial reception continuation
procedure:
To continue serial reception,
before the stop bit for the current
frame is received, read the
RDRF flag, read RDR, and clear
the RDRF flag to 0. The RDRF
flag is cleared automatically
when DTC is activated by an RXI
interrupt and the RDR value is
read.
Receive error processing and