PRECITEC CHRocodile C, Руководство по эксплуатации, Страница: 43 / 63

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This command groups several functions related to encoder triggering. The encoder trigger can
work in two ways:
1. Roundtrip trigger (scanning application)
2. Endless trigger
Roundtrip trigger (scanning application)
The encoder trigger is implemented as a state machine (see figure below). In the idle state, it
waits for the encoder counter of the selected axis to pass the start position (in either direction)
where it generates the first trigger event. Then the trigger interval value is added to the current
position and when this position is reached, the next trigger event is generated. This step is
repeated until the stop position is encountered.
The generation of trigger events is now stopped. If triggering during return movement is
selected, the state machine waits for the stop position to be passed once again and generates
trigger events similarly to the forward movement (the trigger interval is now subtracted instead
of added) until the start position is reached. The state machine then goes back to the idle
state. If no Trigger during return movement is selected, the state machine waits for the start
position to be passed over (during return movement) and then passes to the idle state.
Fig A1-1: Roundtrip Trigger