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Trigger the reader by any method mentioned and notice that only one image is captured per trigger
signal. Set the Delay Type to Time and the Start Delay Time (ms) to 1000 and trigger the reader
again; notice that the image capture and read attempt occur one second after the trigger signal was
sent. Set the Delay Type back to None.
Set the Trigger Type to Continuous (external). This type has the following attributes.
Continuously attempts to find and read a code while the trigger signal is active.
Interval (µs) sets the time between read attempts. This becomes a de facto timeout
when a code has been read.
Delay Type works the same as for Single (external).
Move the Ace of Spades out of the field of view and hold down the Trigger hotkey (keep the left
mouse button held down with the cursor on the hotkey); notice that the illumination LED's blink at a
rate of once per second. Now move the card through the field of view (still holding down the Trigger
hotkey) and notice that the trigger sequence stops when a code is read. You will see a successful
read in the Result History pane.
Change the Interval value to 50000 and hold down the Trigger hotkey. Notice how much more
quickly the reader attempts to read codes (illumination LED's flash more quickly). Move the card
through the field of view again; it is easy to see when the code is successfully read.
Change the Interval value to zero and press Tab or Enter on your keyboard. Notice that the value
automatically sets to 16500µs; this is the minimum acquisition time relating to a maximum frame rate
of about 60 frames per second. Again hold down the Trigger hotkey and move the card through the
field of view. Was the code read? If it wasn't why not? Look at the decode times in the Result
History pane for previous read results of this code. You will likely see that these decode
times are longer than 16.5ms. This means that before the code could be successfully read the
reader has initiated another read attempt. Therefore the Interval value would need to be increased
to something greater than the maximum time to decode a normally readable code.
Set the Trigger Type to Burst (external) (Fig. 71).
Fig. 71 - Trigger Type - Burst (external)
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