121
Absolute Encoder Interface Board
Section 2-3
Note
When PRV(62) is used to read a port’s status, the most recent information will
be read regardless of the PC’s cycle time.
2-2-12 Precautions When Using Pulse Output Functions
The Pulse I/O Board divides the 500 kHz source clock by an integer value to
generate an output pulse frequency. For this reason, the frequency setting
and the frequency actually produced may differ. Refer to the following formula
to calculate the actual frequency.
Pulse Output Structure
Setting frequency:
Output frequency set by User.
Division ratio:
An integer value set at the division circuit to generate output pulses of the set
frequency.
Actual frequency:
Actual output pulse frequency produced by the division circuit.
The difference between the set frequency and the actual frequency increases
as the frequency increases, as shown in the examples in the following table.
2-3
Absolute Encoder Interface Board
2-3-1
Model
Set division ratio (integer value) according
to frequency set by User.
Clock for generating pulses
500 kHz
Division
circuit
Output pulse (Actual frequency)
Actual frequency (kHz) = 500 (kHz) / INT(500 (kHz) / Set frequency (kHz) )
INT: Function to derive integer value
INT (500 / Set frequency): Division ratio
Set frequency (kHz)
Actual frequency (kHz)
45.46 to 50.00
41.67 to 45.45
38.47 to 41.66
31.26 to 33.33
29.42 to 31.25
27.78 to 29.41
20.01 to 20.83
19.24 to 20.00
18.52 to 19.23
10.01 to 10.20
9.81 to 10.00
9.62 to 9.80
5.01 to 5.05
4.96 to 5.00
4.90 to 4.95
3.02 to 3.03
3.00 to 3.01
2.98 to 2.99
50.00
45.45
41.67
33.33
31.25
29.41
20.83
20.00
19.23
10.20
10.00
9.80
5.05
5.00
4.95
3.03
3.01
2.99
Name
Model
Specifications
Absolute Encoder
Interface Board
CQM1H-ABB21
2 inputs for absolute encoders
