Racal Instruments 3152, User Manual

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Using The Instrument 3-29
Use this command up to 4095 times, each time for a different step
and for a different segment number and repeat combination. Note
that the same segment number can be used for different sequence
steps. The SEQ:DEF command does not change the FUNC:MODE
setting. Unless the FUNC:MODE SEQ command is used, the
SEQ:DEF command will have no immediate effect on the output
waveform or function.
The sequence generator goes through the steps in descending
order. In the continuous operating mode, the sequence is repeated
automatically after the last step has been completed. When the
generator is set to operate in Triggered mode, the output stops at
the last point of the last waveform in the sequence. In Gated mode,
the sequence is always completed after the gate stop signal.
If removal of a step from the sequence is required, use the
following command:
SEQuence:DELete <n>
where <n> is the step number to be removed from the sequence.
To delete all sequences, use the following command:
SEQuence:DELete:ALL
CAUTION The above command will destroy sequences previously
loaded into memory.
Triggered Sequence
Advance
Triggered Sequence Advance is a special case sequenced mode.
In Triggered Sequence Advance mode, the Model 3152 idles
between steps until a valid trigger signal is sensed. The trigger
source can be selected from a number of options:
!
An external trigger signal applied to the front panel TRIG IN
connector
!
An internal trigger generator whose period is programmable
!
VXIbus TTLTRG<n> triggers
!
soft triggers.
A sequence operating in Continuous mode can be seen in Figure
3-6. Figure 3-7 shows an example of the same sequence in
Triggered Sequence Advance mode.