Aim-TTI TGA1240 Series, Инструкция по эксплуатации

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48
Sequence Set
−
up
Pressing the
sequence setup
… soft
−
key on the
SEQUENCE
screen (or the
setup
…
soft
−
key next to
sequence
on the
STANDARD WAVEFORMS
screen) calls the sequence set
up screen:
◊
seg: 2 off
◊
♦
wfm wv03
◊
step on: count
◊
cnt: 00001 done
◊
Repeated presses of the
seg
soft
−
key steps the display through the set
−
ups of each of the
16 segments of the sequence. With the exception of segment 1 which is always on (and
therefore has no on
−
off soft
−
key) the 16 segment set
−
ups are identical in format. When
segment 1 is displayed the
segs=
field shows the total number of segments in the current
sequence.
The segment to be set
−
up is selected with the
seg
soft
−
key; the 16 segments can be
selected in sequence with repeated presses of the soft
−
key or by using the rotary control.
Once the segment to be edited has been set the waveform for that segment is selected with the
wfm
(waveform) soft
−
key; the list of all arbitrary waveforms already created is stepped
through with repeated presses of the
wfm
soft
−
key or by using the rotary control.
The criteria for stepping between waveform segments is set by the
step on
soft
−
key. The
default setting is
step on: count
which means that the waveform will step on to the next
segment after the number of waveform cycles specified in the
cnt
(count) field; up to 32768
cycles can be set with
cnt
selected, using direct keyboard entries or by rotary control.
Alternatively, the step on criteria can be set to
trig edge
or
trig level
in the step on
field; trigger edge or trigger level can be mixed with count (i.e. some segments can step on
count, others on the specified trigger condition) but trigger edge cannot be mixed with trigger
level in the same sequence.
If
trig edge
is selected the sequence starts running at the first waveform segment when
sequence is set to
run
and steps to the following segments in turn at each subsequent trigger.
The trigger source can be any of the settings selected on the
TRIGGER IN
setup screen
(called by the TRIG IN key); these are described fully in the Triggered Burst and Gate section. At
each trigger the current waveform cycle plus one further whole cycle are completed before the
waveform of the next segment is started.
If
trig level
is selected the sequence runs continuously through each segment in turn (1
cycle per segment) while the trigger level is true. When the trigger level goes false the waveform
currently selected runs continuously until the level goes true again at which point the sequence
runs continuously through each segment in turn again. The trigger level source can be any of the
settings selected on the
TRIGGER IN
setup screen with the exception of the MAN TRIG key
which can only produce an edge, not a level, when pressed.
Providing the
step on:
field is set to
count
for all segments the waveform sequence can
also be run in Gated and Triggered Burst modes in the same way as simple waveforms; refer to
the Triggered Burst and Gated section for full details.
The individual segments of the sequence can be turned on or off with the
on
−
off
soft
−
key.
Note that turning a segment off will automatically set all subsequent segments off; turning a
segment on will also turn on any others between segment 1 and itself that were previously off.
Segment 1 is always on.
When the whole sequence is defined the set
−
up is constructed by pressing the
done
soft
−
key
which returns the display to the initial
SEQUENCE
screen. The sequence can be run and
stopped from this screen with the
run
and
stop
soft
−
keys respectively.