HP 15c Collector's Edition

Appendix C: Memory Allocation 215
Memory Status (W)
To view the current memory configuration of the calculator, press |
W (memory), holding W to retain the display.
*
The display will be
four numbers,
dd uu pp−b
where:
dd = the number of the highest-numbered register in the data storage
pool (making the total number of data registers dd + 2 because of
R
0
and R
I
);
uu = the number of uncommitted registers in the common pool;
pp = the number of registers containing program instructions; and
b = the number of bytes left before uu is decremented (to supply
seven more bytes of program memory) and pp is incremented.
The initial status of the HP 15c at power-up is:
19 78 00-0
The movable boundary between the data storage and common pools is
always between R
dd
and R
dd + 1
.
Memory Reallocation
There are 99 registers in memory, worth seven bytes each. Ninety-six of
these registers (R
2
to R
97
) are interconvertible between the data storage
and common pools.
The m % Function
If you should require more common space (as for programming) or more
data storage space (but not both simultaneously!), you can make the
necessary register reallocation using m %.
†
The procedure is:
*
W is nonprogrammable.
†
m (dimension) is so called because it is also used (with A through E or V) to
dimension matrices. Above, however, it is used (with %) to “dimension” the size of the
data storage pool.