Manual USB-DIO24-CTR6
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Mode 3: Square Wave Generator
This mode operates like mode 2. The output is high for half of the count and low for the
other half. If the count is even, then the output is a symmetrical square wave. If the count is
odd, then the output is high for (N+1)/2 counts and low for (N-1)/2 counts. Periodic triggering
or frequency synthesis are two possible applications for this mode. Note that in this mode, to
achieve the square wave, the counter decrements by two for the total loaded count, then
reloads and decrements by two for the second part of the wave form.
Mode 4: Software Triggered Strobe
This mode sets the output high and, when the count is loaded, the counter begins to count
down. When the counter reaches zero, the output will go low for one input period. The
counter must be reloaded to repeat the cycle. A low gate input will inhibit the counter.
Mode 5: Hardware Triggered Strobe
In this mode, the counter will start counting after the rising edge of the trigger input and will
go low for one clock period when the terminal count is reached. The counter is retriggerable.
The output will not go low until the full count after the rising edge of the trigger.
