Specifications
Advanced Configuration Features
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For example, say you want to combine a counter block and a compare block in a
nested reflex action. You want the result of the counter to be the operational input to
the compare block. The compare block will then produce a Boolean as its result:
Result 2 (from the compare block) is the result that the nested reflex action will send
to an actual output. Because the result of a compare block needs to be mapped to
a digital action module, result 2 is mapped to channel 4 on an STB DDO 3410 digital
output module.
Result 1 is used only inside the module—it provides the 16-bit operational input to
the compare block. It is mapped to the same STB DDO 3410 digital output module
that is the action module for the compare block.
Instead of specifying a physical channel on the action module for result 1, the
channel is set to none. In effect, you are sending result 1 to an internal reflex buffer
where it is stored temporarily until it is used as the operational input to the second
block. You are not really sending an analog value to a digital output channel.
Number of Reflex Blocks on an Island
An island can support up to 10 reflex blocks. A nested reflex action consumes two
blocks.
An individual output module can support up to two reflex blocks. Supporting more
than one block requires that you manage your processing resources efficiently. If
you are not careful with your resources, you may be able to support only one block
on an action module.
Processing resources are consumed quickly when a reflex block receives its inputs
from multiple sources (different I/O modules on the island and/or virtual modules in
the NIM). The best way to preserve processing resources is to:
z use the always enabled constant as the enable input whenever possible
z use the same module to send multiple inputs to a block whenever possible