Intel
®
81341 and 81342—UARTs
Intel
®
81341 and 81342 I/O Processors
Developer’s Manual
December 2007
906
Order Number: 315037-002US
15.4.11 UART x FIFO Occupancy Register
This register shows the number of bytes currently remaining the Receive FIFO. It can
be used by the processor to determine the number of trailing bytes to remove from the
receive FIFO when the Character Time-out Interrupt is detected. Refer to
15.3.2, “Removing Trailing Bytes In Interrupt Mode” on page 884
. The FOR register is
incremented once for each byte of data written to the Receive FIFO and decremented
once for each byte read.
Table 578. UART x FIFO Occupancy Register - (UxFOR)
Bit
Default
Description
31:7
000 0000h
Reserved
6:0
000 0000
2
FOR[6:0]: Number of bytes (0-63) remaining in the Receiver FIFO
PC
I
IO
P
A
tt
ri
bu
te
s
A
tt
ri
bu
te
s
28
24
20
16
12
8
4
0
31
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
rv
na
ro
na
ro
na
ro
na
ro
na
ro
na
ro
na
ro
na
Unit #
01
Intel XScale
®
Core internal bus address
+2324H (DLAB=x)
+2364H (DLAB=x)
Attribute Legend:
RV = Reserved
PR = Preserved
RS = Read/Set
RW = Read/Write
RC = Read Clear
RO = Read Only
NA = Not Accessible