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pulses, the present period will not be affected, but the subsequent
period will reflect the value.
The gate input, when low, will force the output high. When the gate
input goes high, the counter will start from the initial count. You can
thus use the gate input to synchronize the counter.
With this mode the output will remain high until you load the count
register. You can also synchronize the output by software.
MODE 3 – Square Wave Generator
This mode is similar to Mode 2, except that the output will remain
high until one half of the count has been completed (for even
numbers), and will go low for the other half of the count. This is
accomplished by decreasing the counter by two on the falling edge of
each clock pulse. When the counter reaches the terminal count, the
state of the output is changed, the counter is reloaded with the full
count and the whole process is repeated.
If the count is odd and the output is high, the first clock pulse (after
the count is loaded) decrements the count by 1. Subsequent clock
pulses decrement the count by 2. After time-out, the output goes low
and the full count is reloaded. The first clock pulse (following the
reload) decrements the counter by 3. Subsequent clock pulses
decrement the count by two until time-out, then the whole process is
repeated. In this way, if the count is odd, the output will be high for
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