Datasheet

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DP83849C
8 SD_OPTION 1, RW Signal Detect Option:
1 = Default operation. Link will be asserted following detection of
valid signal level and Descrambler Lock. Link will be maintained as
long as signal level is valid. A loss of Descrambler Lock will not
cause Link Status to drop.
0 = Modified signal detect algorithm. Link will be asserted following
detection of valid signal level and Descrambler Lock. Link will be
maintained as long as signal level is valid and Descrambler re
-
mains locked.
7 DESC_TIME 0, RW Descrambler Timeout:
Increase the descrambler timeout. When set this should allow the
device to receive larger packets (>9k bytes) without loss of syn
-
chronization.
1 = 2ms
0 = 722us (per ANSI X3.263: 1995 (TP-PMD) 7.2.3.3e)
6 RESERVED 0, RO RESERVED:
Must be zero.
5 FORCE_100_OK 0, RW Force 100Mb/s Good Link:
1 = Forces 100Mb/s Good Link.
0 = Normal 100Mb/s operation.
4:3 RESERVED 0,RO RESERVED:
Must be zero
2 NRZI_BYPASS 0, RW NRZI Bypass Enable:
1 = NRZI Bypass Enabled.
0 = NRZI Bypass Disabled.
1:0 RESERVED 0,RO RESERVED:
Must be zero.
Table 35. 100 Mb/s PCS Configuration and Status Register (PCSR), address 16h (Continued)
Bit Bit Name Default Description