As described in , ScanImage 3.5 allows the user to specify a single primary trigger input per board, using the INI file Rig Configuration variable triggerInputTerminal.
ScanImage 3.5 also adds the ability to specify a distinct terminal input as the external trigger input. This allows ScanImage acquisitions to be triggered by any external software which generates a trigger signal (TTL rising edge), e.g. Ephus.
As with the trigger input terminal, ScanImage 3.5 assumes the external trigger input terminal applies for all boards.
See Typical DAQ Board Wiring in Appendix 2 for drawings/photos of typical board connections
The selection of whether the primary or external trigger is used occurs in the Main Controls window:
When the EXT toggle button is depressed (as shown here), all ScanImage boards await their trigger on the external trigger input terminal during GRAB/LOOP acquisitions (but not FOCUS acquisitions).
Otherwise, all boards await their trigger on the trigger input terminal (which is generally connected to the trigger line output generated by ScanImage).
New Variables
externalTriggerInputTerminal: Specifies the single Programmable Function Interface (PFI) terminal which the acquisition, mirror, and Pockels Cell board(s) can all use as their optional external trigger input, which can be enabled from the Main Controls window.
externalTriggerTimeout: Specifies time to wait for external trigger input to arrive. When value is Inf (default), ScanImage will wait indedfinitely for the external trigger signal to arrive following a GRAB/LOOP start.