Specialty Measurement

TTL Measurement

Externally triggered measurements are supported. This can be useful for synchronizing measurements with the operation of an additional device or between multiple instruments. To do so:

  1. Double check that the ttl trigger source is plugged into the trigger port on the controller

  2. Within the instrument interface go to Settings >> Tracker >> General Settings and hit API_DI, in the tracker specific settings toggle with the TTL Trigger On check box.

    The TTL trigger will take the place of your Sampling Frequency setting in any Temporal Scan acquisition until this option is unchecked.

  3. Select a scan measurement profile with a Temporal Scan Acquisition mode, such as Watch Update and start the measurement profile.

  4. Trigger measurements with the TTL signal.

A point is acquired at each 5-0V transition of the input TTL signal, which should be connected directly to the instrument controller.

Buffer control is also available for TTL triggered data. The buffer size can be set in the DI settings dialog and the buffer size is persisted (defaults to 200 pts.), but “TTL Trigger On” is turned off every time the interface is closed. The buffer for TTL data will send its remaining con- tents to SA if you finish the measurement with “Done”, it will clear if you “Abort”.

* Requires tracker firmware version 5.170 (or later).