Teledyne LeCroy QPHY-SAS3 - Manual (Page 38)

In the measure section:
• Rpre(ML) (P9) is the precursor equalization ratio (Rpre) value which was returned from the
SAS3_EYEOPENING script. This is the measured value for TX – Rpre Ref1 (5.4.2.1). This value
must be greater than 2.1 and less than 2.97, inclusive.
• Rpost(ML) (P10) is the postcursor equalization ratio (Rpost) value which was returned from the
SAS3_EYEOPENING script. This is the measured value for TX – Rpost Ref1 (5.4.2.2). This
value must be greater than 3 and less than 4, inclusive.
• VMA(ML) (P11) is the VMA value which was returned from the SAS3_EYEOPENING script. This is
the measured value for TX – VMA Ref1 (5.4.2.3). This value must be greater than 80 mV.
• VHL(ML) (P11) is the VHL value which was returned from the SAS3_EYEOPENING script. This is
the measured value for TX – VMA Ref1 (5.4.2.3). This value must be greater than 850 mV and
less than 1.2 V.
• Rpre (P4) is the precursor equalization ratio (Rpre) value which was calculated as the ratio of the V3
and V2 points in the F4 waveform. This value is provided for additional information only.
• Rpost (P5) is the postcursor equalization ratio (Rpost) value which was calculated as the ratio of the
V1 and V2 points in the F4 waveform. This value is provided for additional information only.
• VMA (P6) is the VMA value which was calculated as the difference between the V2 and V5 points in
the F4 waveform. This value is provided for additional information only.
• VHL (P7) is the VHL value which was calculated as the difference between VH and VL in the F4
waveform. This value is provided for additional information only.
Tx Emphasis Ref2 (IDLE_REF2)
The purpose of this test is to verify that Rpre, RPost, VMA, and VHL are within the specified limits for the
reference 2 coefficient settings.
With the transmitter set to its maximum peak voltage the emphasis coefficients for REF2 must be set to:
Figure 34 – IDLE_REF2 Message Box
38 922545 Rev A