ox16cf950 ETC-unknow, ox16cf950 Datasheet - Page 31

• Manufacturer Part Number: ox16cf950
• Description: Cost Asynchronous Card
• Manufacturer: ETC-unknow

bit mode LSR[2] is no longer a flag and corresponds to the
9
LSR[3]: Received data framing error
logic 0
logic 1
This status bit is set and cleared in the same manner as
LSR[2]. When a framing error occurs, the UART will try to
re-synchronise by assuming that the error was due to
sampling the start bit of the next data item.
LSR[4]: Received break error
logic 0
logic 1
A break condition occurs when the SIN line goes low
(normally signifying a start bit) and stays low throughout
the start, data, parity and first stop bit. (Note that the SIN
line is sampled at the bit rate). One zero character with
associated break flag set will be transferred to the RHR
and the receiver will then wait until the SIN line returns
high. The LSR[4] break flag will be set when this data item
gets to the top of the RHR and it is cleared following a read
of the LSR.
th
OXFORD SEMICONDUCTOR LTD.
bit of the received data in RHR.
No framing error.
Data has been received with an invalid stop
bit.
No receiver break error.
The receiver received a break.
LSR[5]: THR empty
logic 0
logic 1
LSR[6]: Transmitter and THR empty
logic 0
logic 1
LSR[7]: Receiver data error
logic 0
logic 1
In 450 mode LSR[7] is permanently cleared, otherwise this
bit will be set when an erroneous character is transferred
from the receiver to the RHR. It is cleared when the LSR is
read. Note that in 16C550 this bit is only cleared when
all of the erroneous data are removed from the FIFO. In
9-bit data framing mode parity is permanently disabled, so
this bit is not affected by LSR[2].
Transmitter FIFO (THR) is not empty.
Transmitter FIFO (THR) is empty.
The transmitter is not idle
THR is empty and the transmitter has
completed the character in shift register and is
in idle mode. (I.e. set whenever the transmitter
shift register and the THR are both empty.)
Either there are no receiver data errors in the
FIFO or it was cleared by an earlier read of
LSR.
At least one parity error, framing error or break
indication in the FIFO.
OXCF950 DATA SHEET V1.1
Page 31