MAN0964-14-EN_XL4_XL4P_UM
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CHAPTER 4
9.3.7 HSC Functions
The high-speed input on the XL4/XL4 PLUS contains many optional tasks. All of which can be
disabled, or set to an internal pre-assigned register (Assigned %Q) or to one of the external
high speed inputs (External Input #1, 2, 3, or 4), or they can be set as an “overflow interrupt”
or “underflow interrupt” meaning that they will occur when either the Overflow or Underflow
input has been activated.
Disable: When the Dis
able function is active, it will “disable” the high
-speed inputs and no
longer count pulses until it is re-enabled
Latch: When the Latch function is active, it takes the current value of the Accumulator and
moves it into the “Latch Value” register
Preload: When the pre-
load function is active, it will take the value from the “Preload” register
and put it into the “Accumulator” for the corresponding Counter.
Clear: When the clear function is active, it will move a value of 0 into the
“Accumulator” for
the corresponding counter.
Marker: When the marker function is enabled, it acts as a dynamic enable/disable for the
Disable, Latch, Preload, and Clear functions. I
f the marker is enabled and “Assigned %Q” is
selected, then both the “Disable” and the “Disable Marker” bits need to be set high in order to
disable the high-speed input. If the Marker is set for one of the inputs, then the input will need
to be “High” in order to use any of the Disable,
Clear, Preload, or Latch functions.
