Teledyne LeCroy PXA125 - Manual (Page 192)

User Manual PXA125
Programming Reference 4-74
command removes all stop bits and clears the segment table. You can recover
memory segments by using the TRAC:DEF command. You can also use this technique
to resize, or combine waveform segments.
TRACe:SELect
Purpose
This command will select the active waveform segment for the output. By selecting the active segment you
are performing two functions:
1. Successive :TRAC commands will affect the selected segment
2. The SYNC output will be assigned to the selected segment. This behavior is especially important for
sequence operation, where multiple segments form a large sequence. In this case, you can synchronize
external devices exactly to the segment of interest
•
will set the active waveform segment number
Parameter type
Numeric (integer only)
Parameter range
1 to 4096
TRACe:SELect?
Response
The PXA125 will return the active segment number.
Sequenced
Waveforms
Sequenced waveforms are made of a number of arbitrary waveforms,
which can be linked and looped in user-programmable order.
Sequenced waveforms are generated from waveforms stored in the
PXA125 as memory segments. Therefore, before a sequence can be
used, download waveform segments to the arbitrary memory using
TRAC# or DMA methods. Information on how to partition the memory
and how to download waveforms is given in the section entitled
Downloading Arbitrary Waveforms.
An example of how sequenced waveforms work is demonstrated in
figure 1-1a through 1-6d. The sequence generator lets you link and
loop segments in user-defined order. Figure 1-6d shows a sequence
of waveforms that were stored in three different memory segments.
There are a number of tools that you can use to build a sequence
table. The easiest way is of course to use the ArbExplorer program.
Information how to use the ArbExplorer program is given in a later
chapter. In other cases, SCPI programming allows low-level
programming of sequence tables.
Use the information below to understand sequence commands and
how to implement them in your application.