Feedback block
The Feedback block allows the user to create feedback loops in a blueprint.
Feedback block
Description
The Feedback block allows the user to create feedback loops in a blueprint. A feedback loop is a cycle in the data flow in your blueprint. These are allowed only if they go through a Feedback block. Feedback loops that do not go through a Feedback block are disallowed by the Architect. Feedback loops can go through a Superblock if the Superblock contains a Feedback block.
Data is not allowed to flow from a Feedback block directly back to itself. But data can flow from a block "downstream" of the Feedback block (i.e., a block receiving input which has passed through the Feedback block already) back into the Feedback block.
If you make use of a Feedback block within a template block or within a superblock, the feedback stream may not go outside the template block or superblock, but must be contained inside the template or superblock.
FEEDBACK block
Block Type
General
Input/Output ports
There are two input ports:
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Input port 1: Input
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This port is located on the left-hand side of the block.
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This port takes in regular input. It cannot take in feedback input.
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This port can accept any number of fields of any type.
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Input port 2: Feedback
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This port is located on the right-hand side of the block. This is unusual for an input port.
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This port is intended for feedback input. Circular data flows (feedback loops) may go only through this port. Non-circular data flows can go through this port too. However, a non-circular data flow to the Feedback input port does not create a feedback loop.
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This port can accept any number of fields of any type.
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There is one output port:
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Output port
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This produces 'feedback' fields with values derived from the values on the Feedback input port according to the block configuration.
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This carries through all the fields from the regular Input port. (There is an exception in the case where a field on the input port has the same name as a Feedback field, in which case the input port field of the same name is ignored.)
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Functions performed on tags
The output values, time stamps, and qualities are copied from the two input ports.
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Feedback fields are also added on the output port, derived from the input fields on the Feedback port. The block configuration determines which feedback fields are used, as well as how the timestamps, qualities and values of Feedback fields on the output port are derived from the values on the Feedback port.
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All the input fields from the first Input port are carried through to the output port, with the same timestamps, qualities, and values. (There is an exception in the case where a field on the input port has the same name as a Feedback field, in which case the input port field of the same name is ignored.)
NOTE: If more than one Feedback block is used in parallel in a blueprint and if those feedback blocks interact with one another, then the order of execution of those two blocks cannot be guaranteed.
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