Dewetron DEWE-ORION-1616-10 Series, Техническое справочное руководство

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DEWE-ORION-1616-10x
2.5.2 Basic counter organisation
Figure 3 shows the principal of a counter block. The counter consists of 4 inputs. The input “Armed” is need-
ed for starting and triggering the counter. The basic input of a counter is the source pin. The default usage
of this input is event counting. In addition to the gated counting mode the “GATE” input is also the standard
input for period measurement. The AUX input is for special functions like up/down counting or encoder mea-
surement.
ARMED
SOURCE
GATE
AUX (UP / DOWN)
Start / stop trigger
Selected source input
Selected gate input
Selected aux input
OUT
Counter
Counter Value
Figure 3: Counter functions
The counters at DEWE-ORION-1616-10x cards are organized in pairs. The pins of each pair can be routed
to the counter block of the pair counter. This gives the possibility to measure with just one input the frequen-
cy AND also counting the pulses. Also additional pins can be routed to the counter blocks. For example the
ADC-clock can be used to measure the period time if the board is used in the external clocking mode. In this
case also the time information of the measured analog values is not lost.
SOURCE / SOURCE PAIR
GATE / GATE PAIR
AUX / AUX PAIR
Additional
Inputs
Filter Counter
Counter pair
Counter out
Counter out pair
Decoder
Decoder
Filter
Figure 4: Basic counter organization
All the counter functions are triggered with the rising edge of the input signal. If falling edge trigger is required
the inputs can be simple inverted by software settings. To remove glitches at the input a digital filter between
100 nsec and 5 µsec within 7 steps in the filter block can be selected. The following block selects if the
encoder mode is used or not. The pair counter offers an especially selection: It can measure also the input
frequency of the neighbor counter.