HP HP-65 - Introduction; Three Ways to Use the HP-65

Doing Storage Register Arithmetic.
Subtraction. (r, — x — R,): 810 = [n].
Addition, (r, + x > R,): %0 ¥ [n].
Multiplication. (r, X x —> R,): §%0 ¥ [n].
Division. (r, — x > R,): §%0 & [n].
where [n]is a digit 1, . . ., 9. x is unchanged in
these operations.
8. Clearing Registers
= Press X to clear X register. = Press [ [57¢]
to clear entire stack (X, Y, Z, and T) = Press
E to clear all storage registers (R,,...,Ry)
= Power on clears all registers.
9. Programming
Program Memory. = Used to contain user’s
stored program. Capacity: 100 locations = Top
is above 1st location. = Bottom is last location
= The Pointer, an internal part of the calculator,
determines which memory location is executed
or displayed. In W/PRGM Mode, keystrokes
are stored in memory as codes: The address for
top of memory is 00 00. The codes for keys 0-9,
are 00 — 09. For other keys, the code denotes
row and column. Example: Code for (row
8, column 4) is 84.
User Defined Functions. The top row keys are
used to call a user defined function. When the
calculator is turned on, default functions are de-