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7.3.4 TDR Window Register (TDR_WIN), Page 2, address 17h

This register contains sample window control for the Time Domain Reflectometry (TDR) cable diagnostics. The two val-

ues contained in this register specify the beginning and end times for the window to monitor the response to the transmit-

ted pulse. Time values are in 8ns increments. This provides a method to search for multiple responses and also to

screen out the initial outgoing pulse.

7.3.5 TDR Peak Register (TDR_PEAK), Page 2, address 18h

This register contains the results of the TDR Peak Detection. Results are valid if the TDR_CTRL[11] is clear following

sending the TDR pulse.

7.3.6 TDR Threshold Register (TDR_THR), Page 2, address 19h

This register contains the results of the TDR Threshold Detection. Results are valid if the TDR_CTRL[11] is clear follow-

ing sending the TDR pulse

Table 46. TDR Window Register (TDR_WIN), address 17h

Bit

Bit Name

Default

Description

15:8

TDR_START

0, RW

TDR Start Window:

Specifies start time for monitoring TDR response.

7:0

TDR_STOP

0xFF, RW

TDR Stop Window:

Specifies stop time for monitoring TDR response. The Stop Win-

dow should be set to a value greater than or equal to the Start Win-

dow.

Table 47. TDR Peak Register (TDR_PEAK), address 18h

Bit

Bit Name

Default

Description

15:14

RESERVED

0, RO

RESERVED: Writes ignored, read as 0.

13:8

TDR_PEAK

0, RO

TDR Peak Value:

This register contains the peak value measured during the TDR

sample window. If Min Mode control (TDR_CTRL[7]) is 0, this con-

tains the maximum detected value. If Min Mode control is 1, this

contains the minimum detected value.

7:0

TDR_PEAK_TIME

0, RO

TDR Peak Time:

Specifies the time for the first occurrence of the peak value.

Table 48. TDR Threshold Register (TDR_THR), address 19h

Bit

Bit Name

Default

Description

15:9

RESERVED

0, RO

RESERVED: Writes ignored, read as 0.

TDR_THR_MET

0, RO

TDR Threshold Met:

This bit indicates the TDR threshold was met during the sample

window. A value of 0 indicates the threshold was not met.

7:0

TDR_THR_TIME

0, RO

TDR Threshold Time:

Specifies the time for the first data that met the TDR threshold.

This field is only valid if the threshold was met.

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