Datasheet

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DP83849C
8 LOOPBACK_10_DIS 0, RW 10Base-T Loopback Disable:
In half-duplex mode, default 10BASE-T operation loops Transmit
data to the Receive data in addition to transmitting the data on the
physical medium. This is for consistency with earlier 10BASE2 and
10BASE5 implementations which used a shared medium. Setting
this bit disables the loopback function.
This bit does not affect loopback due to setting BMCR[14].
7 LP_DIS 0, RW Normal Link Pulse Disable:
1 = Transmission of NLPs is disabled.
0 = Transmission of NLPs is enabled.
6 FORCE_LINK_10 0, RW Force 10Mb Good Link:
1 = Forced Good 10Mb Link.
0 = Normal Link Status.
5 RESERVED 0, RW RESERVED:
Must be zero.
4 POLARITY RO/LH 10Mb Polarity Status:
This bit is a duplication of bit 12 in the PHYSTS register. Both bits
will be cleared upon a read of 10BTSCR register, but not upon a
read of the PHYSTS register.
1 = Inverted Polarity detected.
0 = Correct Polarity detected.
3 RESERVED 0, RW RESERVED:
Must be zero.
2 RESERVED 1, RW RESERVED:
Must be set to one.
1 HEARTBEAT_DIS 0, RW Heartbeat Disable: This bit only has influence in half-duplex 10Mb
mode.
1 = Heartbeat function disabled.
0 = Heartbeat function enabled.
When the device is operating at 100Mb or configured for full
duplex operation, this bit will be ignored - the heartbeat func
-
tion is disabled.
0 JABBER_DIS 0, RW Jabber Disable:
Applicable only in 10BASE-T.
1 = Jabber function disabled.
0 = Jabber function enabled.
Table 39. 10Base-T Status/Control Register (10BTSCR), address 1Ah (Continued)
Bit Bit Name Default Description