ICS1893 datasheet(102/152 Pages) ICST

102 / 152 page

ICS1893 Rev C 6/6/00

June, 2000

102

Chapter 8

Management Register Set

ICS1893 Data Sheet - Release

8.14.5

Twisted Pair Tri-State Enable, TPTRI (bit 19.7)

The ICS1893 provides a Twisted Pair Tri-State Enable bit. This bit forces the TP_TXP and TP_TXN signals

to a high-impedance state. When this bit is set to logic:

• Zero, the Twisted Pair Interface is operational.

• One, the Twisted Pair Interface is tri-stated.

8.14.6

ICS Reserved (bits 19.12:6)

See Section 8.11.2, “ICS Reserved (bits 16.14:11)”, the text for which also applies here.

8.14.7

Force LEDs On (bit 19.5)

Each ICS1893 provides a Force LEDs On bit as a diagnostic function. This bit overrides the normal

operation of the LEDs and forces them on. When this bit is set to logic:

• Zero, the normal operation of all ICS1893 LEDs is unaffected.

• One, all ICS1893 LEDs forced on.

Note:

The ‘on’state of the LEDs driven from multi-function configuration pins is determined after the pin

is sampled.

8.14.8

ICS Reserved (bits 19.4:1)

See Section 8.11.2, “ICS Reserved (bits 16.14:11)”, the text for which also applies here.

8.14.9

Automatic 100Base-TX Power-Down (bit 19.0)

The Automatic 100Base-TX Power Down bit provides an STA with the means of enabling the ICS1893 to

automatically shut down 100Base-TX support functions when 10Base-T operations are being used. When

this bit is set to logic:

• Zero, the 100Base-TX Transceiver does not power down automatically in 100Base-TX mode.

• One, and the ICS1893 is operating in 10Base-T mode, the 100Base-TX Transceiver automatically turns

off to reduce the overall power consumption of the ICS1893.

Note:

There are other means of powering down the 100Base-TX Transceiver (for example, when the

entire device is isolated using bit 0:10).

ICS1893 датащи(PDF) 102 Page - Integrated Circuit Systems