Instruction manual

Booleans
890USE18300 September 2003 49
Operational
Inputs
Every three-input AND requires three operational input values. Each input is a
Boolean 1 or 0. These inputs may come from some combination of
constant values
digital inputs from modules on the island
digital outputs from the virtual module (See The Virtual Module, p. 28)
an output on the action module (See Using the Action Module as an Input to a
Block, p. 32) written to by the fieldbus master
if the AND is the second part of a nested reflex action (See Nesting Two Reflex
Blocks, p. 36), one of the operational inputs may be the output from the first reflex
block
Physical Output The output from a three-input AND action is a Boolean true (1) or false (0), as shown
in the truth tables that follow. The physical output (See Configuring the Physical
Output from a Reflex Block, p. 27) needs to be mapped to an action module:
The action module may be a digital output module on the island bus. In this case,
you need to specify one of the digital output channels as the destination for the
reflex output.
If the AND is the first action in a nested reflex action, the action module needs to
be the same action module as the one specified for the second reflex block.
Specify the channel as None.
When the output from a block is mapped to a channel on a digital output module,
that channel becomes dedicated to the reflex action and can no longer use data from
the fieldbus master to update its field device. The fieldbus master still has the ability
to write data to this bit address in the NIM, and the reflex action editor lets you use
this data from the fieldbus master as an input to the block.