Chapter 2. Program Organization
20
PACSystems* RX7i, RX3i and RSTi-EP CPU Programmer's Reference Manual
GFK-2950C
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When a parameter is passed by
value result (UDFB inputs only),
the value of its argument is
copied into a local stack memory associated with the called block, and the address of its
argument is saved. All logic within the called block that reads or writes to the parameter is
reading or writing to this stack memory. When the called block completes its execution, the
value in the stack memory is copied back to the actual argument’s address. Thus
, no changes
are made to the actual argument while the called block is executing, but when it completes
execution, the actual argument is updated.
Summary of Contents for PACSystems RSTi-EP
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