This lesson is part of the Sequential Function Charts in Ignition course. You can browse the rest of the lessons below.

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Here is a detailed explanation of how the Jump and Anchor elements function in a Sequential Function Chart.

Video recorded using: Ignition 8.1

Transcript

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[00:00] The jump and anchor SFC elements are a way to connect elements without having to draw the links between them. For example, instead of connecting these two action steps with the long link, I could use a jump and anchor. I'll place a jump by the transition at the top of this chart, and I'll place the corresponding anchor before this action step below. When I start this chart, you'll see that once it reaches the jump, it is able to move the flow to the anchor. Each jump, an anchor is identified by a label, which is a single character. Right now, my jump and anchor are represented by the default character, capital A. These are case sensitive and can be any alphanumeric character, so I could instead maybe represent each label as an exclamation point. Just keep in mind that in order to make use of a jump and anchor, they must share the same label. Additionally, jumps and anchors have a one-to-many relationship where you can have many jumps to a single anchor. For example, if I added another anchor to this chart and gave it the same label, you'll see an error produced for a duplicate anchor. Now, in this example, it would've been easy to draw the link, but take for example, a more complicated chart.

[01:05] In this batch vessel chart, I have another anchor here labeled with the capital E that goes to an error handler, and then in numerous places on the chart, I have a jump with the same label. Now, drawing links from all these locations back to my error handler could be pretty cumbersome and in a very complicated and busy chart, you might have to cross over other elements, which isn't allowed. So in some cases, jumps and anchors are required to let you go to a place in the chart that you wouldn't be able to reach otherwise. When I start this chart, we can see that once an error jump was reached, we could seamlessly enter into the error handling logic. This provides us a great design tool for better managing complex charts.

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