EP80579 Datasheet, PDF (1188/1916 Pages) Intel Corporation – Intel® EP80579 Integrated Processor Product Line

Intel^® EP80579 Integrated Processor
Table 33-20. Offset 05h: LSR - Line Status Register (Sheet 3 of 3)
Description:
View: IA F
Base Address: Base (IO)
Offset Start: 05h
Offset End: 05h
Size: 8 bit
Default: 60h
Power Well: Core
Bit Range
01
00
Bit Acronym
Bit Description
Sticky
Overrun Error: In non-FIFO mode, OE indicates that
data in the receiver buffer register was not read by the
processor before the next character was transferred into
the receiver buffer register, thereby destroying the
previous character. In FIFO mode, OE indicates that all
16 bytes of the FIFO are full and the most recently
OE
received byte has been discarded. The OE indicator is
set to a logic “1” upon detection of an overrun condition
and reset when the processor reads the Line Status
Register.
0 = No data has been lost
1 = Received data has been lost.
Data Ready: DR is set to logic 1 when complete
incoming character has been received and transferred
into the Receiver Buffer Register (RBR) or the FIFO. In
non-FIFO mode, DR is reset to 0 when the receive buffer
is read. In FIFO mode, DR is reset to a logic 0 if the
DR
FIFO is empty (last character has been read from
Receiver Buffer Register) or the RESETRF bit is set in
FCR.
0 = No data has been received
1 = Data available in RBR or the FIFO.
Bit Reset
Value
0h
0h
Bit Access
RO
RO
33.5.3.9
Offset 06h: MSR - Modem Status Register
This 8-bit register provides the current state of the control lines from the modem or
data set (or a peripheral device emulating a modem) to the processor. In addition to
this current state information, four bits of the Modem Status register provide change
information. Bits 03:00 are set to a logic 1 when a control input from the Modem
changes state. They are reset to a logic 0 when the processor reads the Modem Status
register.
When bits 0, 1, 2, or 3 are set to logic 1, a Modem Status interrupt is generated if bit 3
of the Interrupt Enable Register is set.
Intel^® EP80579 Integrated Processor Product Line Datasheet
1188
August 2009
Order Number: 320066-003US