:SPRocess:FFEQualizer:TAPS:AUTo
Instrument:
N1010A
DCA-X
DCA-M
Meas. mode:
Scope
Eye
Jitter
Flex Apps:
FlexDCA
FlexRT
Command Syntax
:SPRocessN:FFEQualizer:TAPS:AUTo {OFF | ON}
Where N identifies one of up to 64 possible operators {1:64} that can be defined as part of a math function. The operators are numbered in the order that they were originally added to the function.
Query Syntax
:SPRocessN:FFEQualizer:TAPS:AUTo?
Description
Turns on and off automatic configuration of taps for a Linear Equalizer operator (LFE) (:FUNCtion:FOPerator FFEQualizer). By default, automatic configuration is on.
- OFF
- Disables automatic tap configuration to enable manual entry of tap values. Use the
:SPRocess:FFEQualizer:TAPScommand to enter the individual tap values. Use the:SPRocess:FFEQualizer:TAPS:NORMalizecommand to automatically adjust the tap values for a maximum equalizer gain of 0 dB (unity). The relative contributions of the tap values are maintained. Use the:SPRocess:FFEQualizer:TSPacingcommand to select tap spacing based on taps-per-bit or seconds. - ON
- Enables automatic tap configuration. Use the
:SPRocess:FFEQualizer:NPRecursorscommand to specify the precursors used for automatic configuration. To enter the number of taps, use the:SPRocess:FFEQualizer:TAPS:COUNtcommand. Automatic tap configuration sets the optimum tap values to open an eye diagram, but requires that you use a PRBS pattern that has a length that is listed in the following table. Inverted PRBS patterns are also supported. The table also lists the generating polynomials. Use the:SPRocess:FFEQualizer:TSPacing:TPBitcommand to enter the tap spacing in number of taps-per-bit. You cannot specify a tap spacing based on time in automatic tap configuration mode. Use the:SPRocess:FFEQualizer:TAPS:RECalculatecommand to automatically recalculate the tap values.
| PRBS | Polynomial | PRBS | Polynomial |
|---|---|---|---|
| 25−1 | x5+x4+x2+x1+1 | 211−1 | x11+x9+1 |
| 26−1 | x6+x5+x3+x2+1 | 212−1 | x12+x9+x8+x5+1 |
| 27−1 | x7+x6+1 | 213−1 | x13+x12+x10+x9+1 |
| 28−1 | x8+x7+x3+x2+1 | 214−1 | x14+x13+x10+x9+1 |
| 29−1 | x9+x5+1 | 215−1 | x15+x14+1 |
| 210−1 | x10+x7+1 |
Beginning with FlexDCA revision A.05.60, use of an *OPC? query to pause program execution while waiting for this command to execute.
The Linear Feedforward Equalizer operator is provided with the 86100D-201/N1010A-201 Advanced Waveform Analysis license.
Example Command Sequence
:FUNCtion2:FOPerator FFEQualizer :SPRocess2:FFEQualizer:TAPS:AUTo ON;*OPC? :SPRocess2:FFEQualizer:TAPS:COUNt 5;*OPC? :SPRocess2:FFEQualizer:NPRecursors 3 :SPRocess2:FFEQualizer:TSPacing:TPBit 2 :SPRocess2:FFEQualizer:BANDwidth:AUTo OFF :SPRocess2:FFEQualizer:BANDwidth 8.0E9 :FUNCtion2:COLor TCOLor4 :FUNCtion2:DISPlay ON *OPC? … // Your code to synchronize execution timing.