I have encountered an issue related to repeated frames in long (>16) frame binary pattern sequences at high (>2000 fps) framerates. I have generated my own python class to drive the Light Crafter allowing for access to all documented commands. This includes full decoding of response packets. At present I am using a 68 frame long sequence operating at 4000 fps for a tracking application using structured light. During initial testing I encountered a double frame occurring at the 17th time slot. Having thoroughly checked my detector electronics and python driver software I was able to eliminate them as a source of error. The problem is consistently repeatable.When a sequence of 68 binary patterns are loaded, and run in auto trigger mode, four of the frames (the 17th, 34th, 51st and 68th all multiples of 17) repeat in two sequential time slots. As a result the actual duration of the sequence is 72 slots. Identical results occur at 3000 and 3800 fps but vanish at 2000 fps. Repeating the process in command trigger mode indicates that all patterns have been loaded correctly and are in the correct sequence. For example a grid of rectangles with one non overlapping rectangle per pattern results in a visible pattern with the doubled frames twice as bright as the others. Several other pattern lengths have been attempted with the duplications occurring at different multiples. The result is repeatable across multiple Light Crafter units as well. While this is not a fatal problem for my present application it is of considerable importance to anybody dealing with timed sequences in the Light Crafter. This may well be associated with skipped frames that occur under external triggering. Are updates to the firmware forthcoming?
It appears that you are using the exposure time of 0 (this is only allowed for <= 24 binary patterns).
Please set the exposure time correctly and see if the problem goes away.
Also note that for > 24 binary patterns, the trigger period cannot exceed (exposure+load-time+buffer-swap-time)
load-time = 235us
buffer-swap-time = 135us
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