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User Manual
E727T0005, valid for E-727
BRO, 2019-06-28
Physik Instrumente (PI) GmbH & Co. KG, Auf der Roemerstrasse 1, 76228 Karlsruhe, Germany
Page 120 / 240
Phone +49 721 4846-0, Fax +49 721 4846-1019, Email
is set to "IIR low-pass filter, 2nd order", the required time depends on the cut-off-
frequency f
g
of the IIR low-pass filter which is given by the
Digital Filter Bandwidth
parameter, ID 0x05000001. For signal frequencies f < f
g
/2, the duration of the
filtering can be estimated as follows:
t ≈ 0.216 / f
g
If required, increase f
g
. Examples:
f
g
= 300 Hz:
t = 0.72 ms
f
g
= 1000 Hz:
t = 0.216 ms
INFORMATION
The DDL table content and the calculated processing parameters will be lost when the controller is
powered down or rebooted.
DDL-Related Commands and Parameters
Command
Description
Notes
DDL
Set DDL Table Values
Can be used to fill the DDL table(s) "manually"
with data
DDL?
Get DDL Table Values
Reads the current content of the DDL tables(s)
DPO
DDL Parameter
Optimization
Recalculates the DDL processing parameters
(
Time Delay Max
, ID 0x14000006, and
Time
Delay Min
, ID 0x14000007), required if the
servo parameters have changed
DTC
Clear DDL Table Data
It is recommended that the content of DDL
tables which are not used be deleted. This
avoids errors due to unsufficient memory space
during the DDL initialization.
On controller power down or reboot, the
content of the DDL tables will be erased
automatically.
DTL?
Get DDL Table Length
Returns the value of the
Max DDL Points
parameter, ID 0x1400000B
TLT?
Get Number of DDL Tables The reported value corresponds to the number
of axes available on the controller
WAV
Set Waveform Definition Since DDL works only in conjunction with the
wave generator output, the waveform must first
be defined
WGO
Set Wave Generator
Start/Stop Mode
The WGO command starts the wave generator
output and provides two modes for the DDL:
"Use and reinitialize DDL" and "Use DDL"
See "How to Work with the DDL" (p. 118) for more information. For detailed command
descriptions see the GCS commands manual PZ281E. For the identifiers of the items which can be
addressed with the commands see "Axes, Channels, Functional Elements" (p. 22).