IMO i3C Lite, Руководство пользователя

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Three different options are available to reset (or set) the current count. They are:
•
Configured Counts per Rev value
When configuring the quadrature function, a value may be specified under the Counts per Rev
column. When rotation produces an increasing count, the quadrature accumulator resets to
zero on reaching the Counts per Rev count. Alternately, when rotation produces a decreasing
count, the quadrature accumulator is set to Counts per Rev
– 1 on the count following zero.
Specifying zero for this value allows the totalizer to count through the full 32-bit range before
resetting.
For example, if your encoder outputs 1024 counts per revolution, the value of 1024 can be
entered into the configuration for Counts per rev. This will result in a counter that produces
counts in the range of 0 to 1023.
•
Ladder control
Setting registers %Q17 or Q19 resets quadrature (HSC) 1 or quadrature (HSC) 3 (respectively)
with no additional configuration. Setting registers %Q18 or Q20 sets quadrature (HSC) 1 or
quadrature (HSC) 3 (respectively) to Counts per Rev
– 1.
•
Direct digital input control (HSC3) [Marker]
When HSC input 1 and 2 are used for quadrature inputs, an additional choice of marker input
becomes available for HSC input 3. The marker input is typically part of an encoder or motion
system that signals when a cycle of motion is complete. When the marker input is triggered,
the accumulator is reset to zero or to Counts per rev - 1 based on rotation direction.
Marker reset operation is enabled when HSC3 is configured for Marker
type. Once selected,
one of several modes is available for marker operation. These modes can be sub-divided into
two groups of marker operation.