I347-AT4 Datasheet, PDF (37/148 Pages) Intel Corporation – Intel® Ethernet Network Connection I347-AT4 Datasheet

Device Functionality—I347-AT4
Table 13. Automatic MAC Interface Power Down
3.6.3
Copper Detect Mode
Register
20_6.2:0
001
Mode
SGMII (System) to Copper
MAC Interface Power Down
Control Bit
16_2.3
MAC Interface Powered
Down
SGMII
The I347-AT4 can be placed in cable detect mode power down modes by selecting
either of the two cable detect modes. Both modes enable the PHY to wake up on its
own by detecting activity on the CAT 5 cable. The status of the cable detect is reported
in register 17_0.4 and the cable detect changes are reported in register 19_0.4.
3.6.3.1
Cable Detect (Mode 1)
Cable detect mode (Mode 1) is entered by setting register 16_0.9:8 to 10.
In Mode 1, only the signal detection circuitry and serial management interface are
active. If the PHY detects energy on the line, it starts to auto-negotiate sending FLPs
for five seconds. If at the end of five seconds the auto-negotiation is not completed,
then the PHY stops sending FLPs and goes back to monitoring receive energy. If auto-
negotiation completes, then the PHY goes into normal 10/100/1000 Mb/s operation. If
during normal operation the link is lost, the PHY re-starts auto-negotiation. If no
energy is detected after five seconds, the PHY goes back to monitoring receive energy.
3.6.3.2
Cable Detect Mode (Mode 2)
Cable detect mode (Mode 2) is entered by setting register 16_0.9:8 to 11.
In Mode 2, the PHY sends out a single 10 Mb/s Normal Link Pulse (NLP) every one
second. Except for this difference, Mode 2 is identical to Mode 1 operation. If the I347-
AT4 is in Mode 1, it cannot wake up a connected device; therefore, the connected
device must be transmitting NLPs, or either device must be woken up through register
access. If the I347-AT4 is in Mode 2, then it can wake a connected device.
3.6.3.3
Normal 10/100/1000 Mb/s Operation
Normal 10/100/1000 Mb/s operation can be entered by turning off cable detect mode
by setting register 16_0.9:8 to 0x0.
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