13
Timing Signals
Single Strobe Output
Synchronization of external devices to the spectrometer’s integration period can be accomplished with the Single Strobe Output. The Single Strobe Output is an
active-high programmable pulse that occurs at a user-defined time during each acquisition cycle. This pulse has a user-defined delay (t
SSDLY
) and a user-defined
width (t
SSH
). Both values are programmable in 1 µs increments for the range of 0 to 65,535 µs.
The timing of the Single Strobe signal output is referenced from a Trigger Event. The Single Strobe Delay defines the time from the Trigger Event until the rising
edge of the Single Strobe output. Note that a programmed Acquisition Delay can cause the Single Strobe to pulse before the start of integration. After the Sin-
gle Strobe Delay has elapsed and the Single Strobe Output has gone high, it will remain active for a duration equal to the Single Strobe Width. The Single Strobe
Output will return to a low or inactive state at the end of the Single Strobe Width.
If the Single Strobe Output is programmed for a longer period than the integration time, it will reset to its inactive state at the end of the integration period.
See timing diagrams later in this section for more information of the Single Strobe Timing.
Synchronous Continuous Strobe
The Continuous Strobe output signal is a programmable pulse that occurs at a user-defined time during each acquisition cycle. The Continuous Strobe is a
series of pulses defined by a user-defined period with a 50% duty cycle. The Continuous Strobe Period (t
CSPER
) has a resolution of 10 µs. The polarity is also
selectable so that the Continuous Strobe signal period starts with either a 0 or 1.
The Continuous Strobe signal is only valid during the integration period (t
INTEG
). The Continuous Strobe period has a resolution of 10 µs for a range of 0 to
655,350 µs. However, the Continuous Strobe signal is only exercised if it can complete a full period within the integration period. If there are multiple Continu-
ous Strobe periods within an integration period, only full periods are realized. This means the time between the last Continuous Strobe period and the end of
integration time is between 0 and t
CSPER
.
For the Continuous Strobe signal to be fully realized for at least one period, the integration time must be greater than or equal to the Continuous Strobe Period.
See timing diagrams for more information about Continuous Strobe Timing.
Triggering Modes
The Ocean ST supports two triggering modes, which are set with the Trigger Mode command. Detailed information about each triggering mode follows. Also,
refer to the External Triggering Options document located on our website at OceanInsight.com.
