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CHAPTER 14 SERIAL INTERFACE UART
(b) Asynchronous serial interface status register (ASIS)
ASIS is read with an 8-bit memory manipulation instruction.
When RESET is input, its value is 00H.
Address: FF86H After Reset: 00H R
Symbol
7
6
5
4
3
2
1
0
ASIS
0
0
0
0
0
PE
FE
OVE
PE
Parity Error Flag
0
No parity error
1
Parity error
(Transmit data parity does not match)
FE
Framing Error Flag
0
No framing error
1
Framing error
Note 1
(Stop bit not detected)
OVE
Overrun Error Flag
0
No overrun error
1
Overrun error
Note 2
(Next receive operation was completed before data was read from receive buffer register)
Notes 1. Even if a stop bit length of two bits has been set to bit 2 (SL) in the asynchronous serial interface
mode register (ASIM), stop bit detection during a receive operation only applies to a stop bit
length of 1 bit.
2. Be sure to read the contents of the receive buffer register (RXB) when an overrun error has
occurred.
Until the contents of RXB are read, further overrun errors will occur when receiving data.
Summary of Contents for mPD780973 Series
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