Instruction Manual

Rockwell Automation Publication 1769-UM006E-EN-P - July 2013 41
Module Operation Chapter 2
Program State Run (PSR)
Program State Run lets you specify that the output should continue to be
controlled by the module as if it were in the Run state. That is, events on the
module or changes in the output image will affect the physical outputs without
regard to the Program_HLS or UDSS state indicated. When this bit is set, the
corresponding OutnProgramMode and OutnProgramValue bits are ignored.
PSR sets the module according to the value configured for Output Program State
Run, as described on
page 76.
ATTENTION: Selecting this option lets outputs change state while ladder
logic is not running. You must take care to assure that this does not pose a
risk of injury or equipment damage when selecting this option.
IMPORTANT
The prescan initiated by some controllers could have an effect on the
outputs. To overcome any changes in physical output states caused by
this, retentive output instructions (for example, latch or unlatch) should
be used when bit manipulations are done on the output image of this
module in ladder logic.
This applies to a wide range of bits when Program State Run is selected,
because presetting a counter, enabling a range, changing a mask, and
changing module configuration array settings can cause ranges and
outputs to change state.