Ocean Optics S2000 - Manual (Page 110)

source to supply the voltage, as it is based on a referenced ground and your reference may be different from
ours. Using Pin 3 to supply voltage ensures that the spectrometer will receive the appropriate voltage for the
trigger event.
2. Supply a line from Pin 8 of the J2 Accessory Connector to your triggering device. (See figure on page 109 for
pin location.)
3. Set your acquisition parameters in the software via the Acquisition Dialog Bar or the Configure Data
Acquisition dialog box. To access the dialog box, click the Data Acquisition icon or select Spectrum |
Configure Data Acquisition from the menu.
4. Select Spectrum | Configure Data Acquisition from the menu. Choose the External Trigger page and select
Software Trigger.
5. To save processed data with each external trigger, enable the Automatically save file on trigger box. If you
enable this function, you will be presented with a file save dialog box with each trigger. To avoid manually
naming a file for each trigger, you can enable the Autoincrement Filenames function by selecting File |
Autoincrement Filenames | Enabled from the menu. Choose a base name and starting index for the
autoincremented files.
6. Once you select an external trigger mode, it will appear on your computer that your spectrometer is un-
responsive. Instead, it is waiting for the trigger. Activate your triggering device. The acquisition parameters,
the name of the window acquiring data and the trigger mode are all displayed in the main status bar.
It is important to note that since this is a level-triggered mode, the amount of delay between the trigger pulse and
when a spectrum is acquired is indeterminate because the delay is dependent upon:
" how fast the software polls the Pin 8 line and recognizes it is HIGH
" the amount of time until the start of the next integration period
In this edge-triggered mode, the spectrometer is idle until you apply the initial trigger to the spectrometer. With
each trigger, the following occurs:
1.
the spectrometer stops taking its current scan and data is transferred to the software
2. the spectrometer begins a new scan
3. the spectrometer integrates until another trigger is applied
In the Synchronization Mode, the integration time is set by the frequency of triggers applied to the spectrometer.
The effective integration time is the time between rising edges of signals applied to Pin 5 of the J2 Accessory
Connector. All other acquisition parameters are set in the software. The source for the integration clock is the
external triggering device itself, such as a periodic TTL signal.
Use the Synchronization Mode if you:
" must synchronize your scans to an external clock source
" are using a lock-in amplifier
" are using a chopper
To Use the Synchronization Mode:
1. Supply a line from your triggering device to Pin 3 of the J2 Accessory Connector to provide the positive
voltage +5VDC to the spectrometer. (See figure on page 109 for pin location.) We do not advise using an
outside source to supply the voltage, as it is based on a referenced ground and your reference may be different
from ours. Using Pin 3 to supply voltage ensures that the spectrometer will receive the appropriate voltage for
the trigger event.
2. Supply a line from Pin 5 of the J2 Accessory Connector to your triggering device. (See figure on page 109 for
pin location.)
3. Set other acquisition parameters in the software via the Acquisition Dialog Bar or the Configure Data
Acquisition dialog box. To access the dialog box, click the Data Acquisition icon or select Spectrum |
Appendix F
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External Synchronization Trigger