Rohm LAPIS SEMICONDUCTOR ML620Q503, User Manual

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ML620Q503/Q504 User's Manual
Chapter 14 UART with FIFO(UARTF)
FEUL620Q504 14-22
14.3.6 Error Status
(a)
Overrun error
An overrun error indicates that the data in RBR was not read before the next character was sent to RBR to
overwrite the previous character.
At this time, UF0OER of UAF0LSR is set.
(b) Parity error
A parity error indicates that the parity of the received data and the received parity bit did not match. At this
time, UF0PER of UAF0LSR is set.
Note that, this error will only occur when parity is enabled.
In FIFO mode, this bit indicates that an error exists for the leading data. If a parity error occurs in the data
that is not the leading data in the FIFO, it is not reflected to UF0PER of UAF0LSR.
(c)
Framing error
A framing error indicates that there is no valid stop bit in the received character. This error will occur when
the stop bit after the last data bit or after the parity bit is "0" (spacing level).
At this time, UF0FER of UAF0LSR is set.
In FIFO mode, this is related to a specific character in the FIFO. UF0FER indicates that an error is present
when that character comes to the beginning of the FIFO.
(d)
Break interrupt
A break interrupt indicates that the input data received was maintained in the spacing ("0") state during the
transmission of one frame (start bit + data bit + parity bit + stop bit).
At this time, UF0BI of the UAF0LSR register is set.
In FIFO mode, this is related to a specific character in the FIFO. UF0BI indicates that the break character is
present at the beginning of the FIFO.