Appendix A Stack Lift And Last X; Digit Entry Termination; Stack Lift; Disabling Operations - HP -10C Owner's Handbook Manual

Appendix A
Stack Lift and LAST X
Your HP-10C calculator has been designed to operate in a natural manner. As
you have seen as you worked through this handbook, you are seldom required to
think about the operation of the automatic memory stack—you merely work
through calculations in the same way you would with a pencil and paper,
performing one operation at a time.
There may be occasions, however—especially as you program the HP-10C—
when you wish to know the effect of a particular operation upon the stack. The
following explanation should help you.

Digit Entry Termination

Most operations on the calculator, whether executed as instructions in a
program or pressed from the keyboard, terminate digit entry. This means that
the calculator knows that any of these operations are part of a new number. The
", ., and " operations do not terminate digit entry.

Stack Lift

There are three types of operations on the calculator, depending upon how they
affect the stack lift. These are stack-disabling operations, stack-enabling
operations, and neutral operations.

Disabling Operations

There are four stack-disabling operations on the calculator. These operations
disable the stack lift, so that a number keyed in after one of these operations
writes over the current number in the displayed X-register and the stack does
not lift. These special disabling operations are:
v ` z w

Enabling Operations

Most of the operations on the keyboard, including one- and two-number
mathematical functions like x and *, are stack-enabling operations. This
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