HD6473837H Datasheet, PDF (293/562 Pages) Renesas Technology Corp – Hardware Manual

Start
1
Read bits OER, PER, and
FER in SSR
OER + PER +
Yes
FER = 1
No
1. Read bits OER, PER, and
FER in the serial status
register (SSR) to
determine if a receive
error has occurred.
If a receive error has
occurred, receive error
processing is executed.
2 Read bit RDRF in SSR
No
RDRF = 1?
Yes
Read received data in RDR
4 Receive error processing
Yes
3
Continue receiving?
No
A
2. Read the serial status register
(SSR), and after confirming
that bit RDRF = 1, read
received data from the receive
data register (RDR).
When RDR data is read, RDRF
is automatically cleared to 0.
3. To continue receiving data,
read bit RDRF and finish
reading RDR before the stop
bit of the present frame is
received.
When data is read from RDR,
RDRF is automatically cleared
to 0.
Clear bit RE in SCR3 to 0
End
4
Start receive
error processing
Yes
OER = 1?
No
Yes
FER = 1?
No
Yes
PER = 1?
4. When a receive error occurs,
read bits OER, PER, and FER
in SSR to determine which
error (s) occurred.
After the necessary error
processing, be sure to clear
the above bits all to 0.
Data receiving cannot be resumed
Overrun error
while any of bits OER, PER, or
processing
FER is set to 1.
When a framing error occurs,
a break can be detected by
Break?
reading the RXD pin value.
Yes
No
Framing error
processing
No
Clear bits OER, PER, and
FER in SSR to 0
Parity error
processing
End receive error
processing
A
Figure 10.14 Typical Serial Data Receiving Flow Chart in Asynchronous Mode
276