Racal Instruments 3152, User Manual

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Using The Instrument 3-18
The query:
TRIGger:COUNt?
queries the burst count and returns an integer.
Selecting the
Trigger Source
When an external source is not available, the operator has the
option to use either the built-in trigger generator or a TTLTRG<n>
signal to stimulate its output. Use the following command to select
the trigger source for the instrument:
TRIGger:SOURce:ADVance {EXTernal | INTernal | TTLTrg<n>}
EXT is the default trigger source for the Model 3152. Select the
TTLT<n> option with <n> ranging from 0 to 7 to use one of the
TTLTRG lines available on the backplane. Select INT to use the
internal trigger generator. Remember to program the period of this
generator (as shown later).
The query:
TRIGger:SOURce:ADVance?
queries the trigger source and returns EXT, INT or TTLT<n>.
Using the Internal
Trigger Generator
The internal trigger generator is a free-running generator which is
asynchronous with the main output generator. When the internal
trigger source is selected, the front panel TRIG IN signal is inactive.
The internal trigger generator is also available in Burst mode, but
has no effect in Gated mode. To use the internal trigger generator,
place the instrument in Triggered mode, but select the internal
trigger generator as the trigger source. Then use the following
command to program an internal trigger period:
TRIGger:TIMer <value>
The period of the internal trigger generator can be programmed
from 15 µs to 1000 s. The default period is 100 µs. The internal
trigger generator is ignored when either an external or TTLT source
is enabled.
The query:
TRIGger:TIMer?
queries the period of the internal trigger generator and returns a
value in seconds.