NEC PD78F9488 User Manual
Page 201
CHAPTER 11 SERIAL INTERFACE 20
User’s Manual U15331EJ4V1UD
201
(c) Asynchronous serial interface status register 20 (ASIS20)
ASIS20 is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input sets ASIS20 to 00H.
PE20
0
1
Parity error flag
No parity error occurred
A parity error occurred (when the transmit parity and receive parity did not match)
No framing error occurred
A framing error occurred (when stop bit was not detected)
Note 1
No overrun error occurred
An overrun error occurred
Note 2
(when the next receive operation was completed before data was read from reception buffer register 20)
FE20
0
1
0
1
Framing error flag
Overrun error flag
OVE20
0
0
0
0
0
PE20
FE20
OVE20
ASIS20
7
6
5
4
Symbol
Address
After reset
R/W
FF71H
00H
R
3
<2>
<1>
<0>
Notes 1. Even when the stop bit length is set to 2 bits by setting bit 2 (SL20) of asynchronous serial
interface mode register 20 (ASIM20), the stop bit detection at reception is performed with 1 bit.
2. Be sure to read receive buffer register 20 (RXB20) when an overrun error occurs. If not, an
overrun error will occur every time data is received.