DP83640_08 Datasheet, PDF (68/124 Pages) National Semiconductor (TI) – Precision PHYTER - IEEE® 1588 Precision Time Protocol Transceiver

14.2.10 Energy Detect Control (EDCR)
This register provides control and status for the Energy Detect function.
Bit
Bit Name
15
ED_EN
14
ED_AUTO_UP
13
ED_AUTO_DOWN
12
ED_MAN
11
ED_BURST_DIS
10
ED_PWR_STATE
9
ED_ERR_MET
8
ED_DATA_MET
7:4
ED_ERR_COUNT
3:0
ED_DATA_COUNT
TABLE 36. Energy Detect Control (EDCR), address 0x1D
Default
0, RW
1, RW
1, RW
0, RW/SC
0, RW
0, RO
0, RO/COR
0, RO/COR
0001, RW
0001, RW
Description
Energy Detect Enable:
Allow Energy Detect Mode.
Energy Detect Automatic Power Up:
Automatically begin power up sequence when Energy Detect Data
Threshold value (EDCR[3:0]) is reached. Alternatively, the device could
be powered up manually using the ED_MAN bit (ECDR[12]).
Energy Detect Automatic Power Down:
Automatically begin power down sequence when no energy is detected.
Alternatively, the device could be powered down using the ED_MAN bit
(EDCR[12]).
Energy Detect Manual Power Up/Down:
Begin power up/down sequence when this bit is asserted. When set,
the Energy Detect algorithm will initiate a change of Energy Detect state
regardless of threshold (error or data) and timer values. In managed
applications, this bit can be set after clearing the Energy Detect interrupt
to control the timing of changing the power state.
Energy Detect Burst Disable:
Disable bursting of energy detect data pulses. By default, Energy Detect
(ED) transmits a burst of 4 ED data pulses each time the CD is powered
up. When bursting is disabled, only a single ED data pulse will be sent
each time the CD is powered up.
Energy Detect Power State:
Indicates current Energy Detect Power state. When set, Energy Detect
is in the powered up state. When cleared, Energy Detect is in the
powered down state. This bit is invalid when Energy Detect is not
enabled.
Energy Detect Error Threshold Met:
No action is automatically taken upon receipt of error events. This bit is
informational only and would be cleared on a read.
Energy Detect Data Threshold Met:
The number of data events that occurred met or surpassed the Energy
Detect Data Threshold. This bit is cleared on a read.
Energy Detect Error Threshold:
Threshold to determine the number of energy detect error events that
should cause the device to take action. Intended to allow averaging of
noise that may be on the line. Counter will reset after approximately 2
seconds without any energy detect data events.
Energy Detect Data Threshold:
Threshold to determine the number of energy detect events that should
cause the device to take actions. Intended to allow averaging of noise
that may be on the line. Counter will reset after approximately 2 seconds
without any energy detect data events.
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