
XRT7245
DS3 UNI FOR ATM
á
PRELIMINARY
REV. 1.03
266
The contents of this register reflect the total number of
valid cells that the Receive Cell Processor has received
since the last reading of this register. This register is
reset upon read.
Finally, the user can also monitor the total number of
cells that have been discarded (either due to HEC
errors, Idle Cell removal, or User cell filtering) by
reading the PMON Discarded Cell Count Registers
(Address = 36h, 37h). The bit-format of this register
is presented below.
The contents of these registers reflect the number of
cells that have been discarded since the last read of
these registers. These registers are reset upon read.
7.3.2.5
In numerous applications the payload portion of the
incoming cells will be scrambled by the Transmit Cell
Processor, within the Far End Transmitting terminal.
These cells are scrambled in order to prevent the user
data from mimicking framing or control bytes. There-
Cell Payload De-Scrambling
fore, the Receive Cell Processor provides the user
will the option of de-scrambling the payload of these
cells in order to restore the original content of the cell
payload. (Please note that this cell de-scrambler
presumes that the cell payload were scrambled via
the scrambling generating polynomial of x
43
+ 1.) The
user can configure this option by writing a “1” to Bit 2
(De-Scramble Enable) of the Rx CP Configuration
Register, as depicted below.
PMON Received Valid Cell Count—MSB (Address = 34h)
B
IT
7
B
IT
6
B
IT
5
B
IT
4
B
IT
3
B
IT
2
B
IT
1
B
IT
0
Rx Valid Cell Count—High Byte
RUR
RUR
RUR
RUR
RUR
RUR
RUR
RUR
0
0
0
0
0
0
0
0
PMON Received Valid Cell Count—LSB (Address = 35h)
B
IT
7
B
IT
6
B
IT
5
B
IT
4
B
IT
3
B
IT
2
B
IT
1
B
IT
0
Rx Valid Cell Count—Low Byte
RUR
RUR
RUR
RUR
RUR
RUR
RUR
RUR
0
0
0
0
0
0
0
0
PMON Discarded Cell Count—MSB (Address = 36h)
B
IT
7
B
IT
6
B
IT
5
B
IT
4
B
IT
3
B
IT
2
B
IT
1
B
IT
0
Cell Drop Count—High Byte
RUR
RUR
RUR
RUR
RUR
RUR
RUR
RUR
0
0
0
0
0
0
0
0
PMON Discarded Cell Count—LSB (Address = 37h)
B
IT
7
B
IT
6
B
IT
5
B
IT
4
B
IT
3
B
IT
2
B
IT
1
B
IT
0
Cell Drop Count—Low Byte
RUR
RUR
RUR
RUR
RUR
RUR
RUR
RUR
0
0
0
0
0
0
0
0