Trigger source
These commands enable you to disable the trigger, select the trigger source from one of the eight VXI backplane triggers or to select an external trigger. For external triggering, connect a TTL trigger signal to the TRIGGER INPUT connector. Ensure however, that this socket is not disabled for your application by a higher priority mode having been selected. The order of priority is as follows:
FSK logic input Memory sequencing Sweep trigger
All three modes of operation may be enabled at the same time, but only one mode will be active, the one with the highest priority. Therefore ensure that, for example, FSK and memory sequencing are not enabled when selecting sweep triggering otherwise the triggering will have no effect. Trigger source selection is as follows:
TRIGGER
:SOURCE
Select trigger source.
Data type : Character Program Data (HOLD, IMMEDIATE, TTLTRG0, TTLTRG1, TTLTRG2, TTLTRG3, TTLTRG4, TTLTRG5, TTLTRG6, TTLTRG7, BUS, EXTERNAL). HOLD means no trigger.
Allowed suffices : | None |
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Default suffix : | None |
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Example: | TRIGGER:SOURCE EXTERNAL | |
TRIGGER:SOURCE? | Prepares message containing information on Trigger Source setting in | |
| the following format: | |
| :TRIGGER:SOURCE <source> | |
| where | <source> is character program data defining the trigger |
|
| source. |
Examples: | :TRIGGER:SOURCE EXTERNAL | |
| :TRIGGER:SOURCE TTLTRG3 |
Sources
BUS: | The trigger is generated over the GPIB or VXI interface. The group execute |
| trigger (GET) provides the trigger over IEEE 488.1 |
HOLD: | Selecting this means the event detection is disabled. |
IMMEDIATE: | No waiting for an event to occur. |
TTLTRG | The VXI backplane TTLTRG triggers provide the source. |
EXTERNAL: | An external trigger is provided via the TRIGGER INPUT socket. |