USB-OI16
Seite 6
3.5
Counters with Pulse Time Measurement
The USB-OI16 features two 32-bit counters allowing the
connection of incremental encoders.
The counter inputs (A, B, and Reset) are configured by
software and can be reached then at the first digital input
pins (counter 1: I1-I3; counter 2: I4-I6).
The following table and figure shows the pin assignment of
the counter inputs at the 37-pin D-Sub female:
The USB-OI16 counts the number of
incoming pulses (max. 250kHz)
sampled at the connection of signal
A. If the maximum counting range is
reached, the counter will be reset to
the minimum value of the counting
range.
If the external counter reset is
connected, the counter can be reset
at any time.
In comparison to a counter, the quadrature decoder considers the counting direction by decoding a
second phase-shifted signal.
To activate the counting function, the respective digital lines of the USB-OI16 must be assigned to the
counter via software.
Function
Description
Max. pulse frequ.
Connection
Pins/Counter
Counting range
Counter
count
250kHz
Signal A
1
0..2
32
-1
Up/Down counter
count
100kHz
Signal A, Signal B
2
-2
31
.. 2
31
-1
Incremental encoder count
100kHz
Signal A, Signal B
2
-2
31
.. 2
31
-1
Pulse time
measurement
measure time
betw. 2 edges,
resolution
41,67ns
250kHz
Signal A
1
0 - 178,96s
Please refer to the relevant documentation of your product for further information about connecting
your incremental encoder.
Counter 1
D-Sub37
Counter 2
D-Sub37
Signal A
11
Signal A
31
Signal B
30
Signal B
13
Reset
12
Reset
32
