IMO i3C Lite, User Manual

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12.3.2 Totalize
In totalize mode, the accumulator is simply incremented each time the input transitions in a specific
direction. Totalize mode is configurable to specify the edge (rising or falling) on which the
accumulator is incremented.
Three different options are available to reset the current count.
•
Configured reset value
When configuring the Totalize function, a value may be specified under the Counts per Rev
column. When the totalizer accumulator reaches the value - 1, the accumulator will reset to
zero on the next count. Specifying zero for this value allows the totalizer to count through
the full 32-bit range before resetting.
•
Ladder control
Setting registers %Q17-20 reset HSC1-4 (respectively) with no additional configuration.
When these registers are asserted, the associated totalizer accumulator is reset and held at
zero (level sensitive).
•
Direct digital input control (HSC1 and HSC2 only)
HSC3 (%I11) and HSC4 (%I12) may be configured as hardware digital reset signals for HSC1
and HSC2 (respectively). To enable these inputs as reset signals, specify the type as Totalize
Reset (note that the corresponding Totalize HSC must be previously configured before this
option is available). The direct digital reset controls are edge sensitive with the edge polarity
configurable.
NOTE: Maximum direct digital reset latency is 100
μ
s.
The totalize function also supports an option which compares the current accumulator value with a
supplied Preset Value (PV), which is provided through a %AQ, and drives a physical digital output based
on the that comparison.
This option (available for HSC1 and HSC2 only) drives Q1 or Q2 output point (respectively) once the
associated totalizer accumulator reaches (or exceeds) the PV value. To enable this function, the
corresponding PWM function output (Q1 or Q2) must be configured for HSCx Output.
NOTE: Q1 and Q2 are PWM function outputs that may be configured independently as one of the
following: standard digital output, PWM, or HSCx output.
Preset values may be modified during run-time. A preset value of zero disables (resets) the totalizer
compare function output causing the output to remain low.
Rising Edge Signal Falling Edge Signal