Sutron Corporation 8310 & 7310 Users Manual 8800-1125Rev. 2.7 (BETA) 4/16/2014 pg. 85
ResetCount instructs the 8310 to reset the counter each time a measurement is made. The
default setting for ResetCount is NO, meaning that the counter will not be reset with each
measurement but will keep going up as an accumulator or totalizer. The counter is 32 bits and
will eventually roll over at 2^32 counts. Any calibration of a counter sensor will reset the
accumulator to go up 2^32 counts from the calibration point.
Some instruments do not have a clean output signal and the 8310 may make a measurement
and detect 2 or 3 counts where only one count was generated. When this happens, you can use
FIlterValue to help eliminate the erroneous counts. Most mechanical switches, like a tipping
bucket output, have a switch bounce, so a filter should be used to eliminate false counts. A
value of 0 specifies no debouncing while a value of 1 to 255 requires the input to remain in each
state for filter_value*0.5ms in order for the system to register a count.
A good rule of thumb for selecting the filter value is to set it to the width in milliseconds of the
narrowest pulse to be measured. This assumes that the switch bounce period is less than half
the active period. Filter does limit the maximum frequency that can be reliably measured as
follows:
Frequency of a square wave = 1/(FilterValue*2*.0005)
All counter inputs include a 100K pullup to +5V.
UpdateOnChange: when “Yes”, the measurement will execute when the counter input changes.
This measurement occurs in addition to the defined schedule.
Constant
Constant input types are primarily used for testing.
When TestMode=No, the value of ConstValue is output. When TestMode=YES, the system
provides data according the value of ConstValue:
TickCount (ticks have units of milliseconds, not synronized to any
particular time)
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