opto engineering ITALA - Encoder Interface; Encoder Output Mode; Encoder Mode

Itala | INSTRUCTION MANUAL
6.10.1 Encoder interface
Itala can be used to monitor incremental encoders.
A-B pins of quadrature encoders can be connected to the opto-isolated input pins of Itala cameras.
The electrical specifications are listed in Table 7 and Table 5.1.
The maximum input frequency of Itala encoder interface is approximately 30KHz.
This is mainly due to the response times of the opto-isolated circuitry.
NOTE: In case the input frequency is higher than the nominal specifications, sampling errors may
occur and, consequently, errors may arise during the encoder monitoring.
6.10.2 Encoder output mode
The EncoderOutputMode feature selects one of two following driving modes (see Fig.67):
• direction mode: encoder position is incremented only in one direction.
When moving direction changes, the encoder counter stops counting until the moving direc-
tion changes again.
In this configuration, motion reverse is not considered.
• position mode: encoder position is incremented only in one direction.
When moving direction changes, the encoder counter starts decrementing until the moving
direction changes again.
In this configuration, motion reverse is therefore considered.
Encoder Value
(direction mode)
Moving forward
Moving backward
0
1
2
3 3 34 4 4
5
6 6 6
7 7 9 10
11
12
13
5 5
2
8
Moving forward
Object position
0
1
2
3
7 84 7 9
5
6
7
7
15
16
17
18
7
7
Encoder Value
(
position mode)
0
1
2
3
3 34 4 4
5
6
6 6
7 7
9 10 11
12
13
5 5
2
8
10
11
12
13
14
Figure 67: The two different driving modes of the encoder block: (figure above) direction mode
and (figure below) position mode.
6.10.3 Encoder mode
The encoder counter can be incremented/decremented with two different approaches:
• High resolution mode: encoder counter is updated (incremented or decremented) for every
commutation of Encoder A or Encoder B signal.
v1.12 - eng 90