B

User Memory and the Stack

This appendix covers

„The allocation and requirements of user memory,

„How to reset the calculator without affecting memory,

„How to clear (purge) all of user memory and reset the system defaults, and

„Which operations affect stack lift.

Managing Calculator Memory

The HP 33s has 31KB of user memory available to you for any combination of stored data (variables, equations, or program lines). SOLVE, FN, and statistical calculations also require user memory. (The FN operation is particularly "expensive" to run.)

All of your stored data is preserved until you explicitly clear it. The message & " means that there is currently not enough memory available for the operation you just attempted. You need to clear some (or all) of user memory. For instance, you can:

„Clear any or all equations (see "Editing and Clearing Equations" in chapter

6).

„Clear any or all programs (see "Clearing One or More Programs" in chapter

12).

„Clear all of user memory (press {c{}).

To see how much memory is available, press {Y. The display shows the number of bytes available.

To see the memory requirements of specific equations in the equation list:

1.Press Hto activate Equation mode. (  ! ! or the left end of the current equation will be displayed.)

User Memory and the StackB–1