Owners manual

Interfaces
H3 Datasheet(Revision1.2) Copyright© 2015 Allwinner Technology Co.,Ltd.All Rights Reserved. Page 475
3
R
0
FE
Framing Error
This is used to indicate the occurrence of a framing error in the receiver. A
framing error occurs when the receiver does not detect a valid STOP bit in
the received data.
In the FIFO mode, since the framing error is associated with a character
received, it is revealed when the character with the framing error is at the
top of the FIFO. When a framing error occurs, the UART tries to
resynchronize. It does this by assuming that the error was due to the start
bit of the next character and then continues receiving the other bit i.e. data,
and/or parity and stop. It should be noted that the Framing Error (FE) bit
(LSR[3]) is set if a break interrupt has
occurred, as indicated by Break Interrupt (BI) bit (LSR[4]).
0: no framing error
1:framing error
Reading the LSR clears the FE bit.
2
R
0
PE
Parity Error
This is used to indicate the occurrence of a parity error in the receiver if the
Parity Enable (PEN) bit (LCR[3]) is set. In the FIFO mode, since the parity
error is associated with a character received, it is revealed when the
character with the parity error arrives at the top of the FIFO. It should be
noted that the Parity Error (PE) bit (LSR[2]) is set if a break interrupt has
occurred, as indicated by Break Interrupt (BI) bit (LSR[4]).
0: no parity error
1: parity error
Reading the LSR clears the PE bit.
1
R
0
OE
Overrun Error
This occurs if a new data character was received before the previous data
was read. In the non-FIFO mode, the OE bit is set when a new character
arrives in the receiver before the previous character was read from the RBR.
When this happens, the data in the RBR is overwritten. In the FIFO mode, an
overrun error occurs when the FIFO is full and a new character arrives at the
receiver. The data in the FIFO is retained and the data in the receive shift
register is lost.
0: no overrun error
1: overrun error
Reading the LSR clears the OE bit.
0
R
0
DR
Data Ready
This is used to indicate that the receiver contains at least one character in
the RBR or the receiver FIFO.
0: no data ready
1: data ready
confidential