on or select
the menu command
View > Stacks to create
a view object that allows you to monitor the nesting stack and the
master control relay (MCR) stack:
nesting stack stores up to seven entries. For each entry, the
nesting stack stores the states of the RLO and the OR bits of the
status word. An entry in the nesting stack is made for each
instruction that starts a new logic string. These instructions are:
And (A), And Not (AN), Or (O), Or Not (ON), Exclusive Or (X), and
Exclusive Or Not (XN).
stack stores up to eight levels of nesting for a master control
relay. Each level shows the status of the RLO bit of an MCR(
instruction, which begins an MCR area.
"Stacks" View Object