HP 48G Series User Manual

Lesson 12: Understanding Memory
Thus far it has been convenient to think of the HP 48 as a
calculator—albeit an advanced calculator. However, when considering
its memory, it is better to think of it as a computer.
The basic unit of storage on a desktop computer is the named file. On
the HP 48 the basic unit of storage is the named object, or variable.
Unnamed objects can exist on the stack, but, like computer files, must
be named in order to be saved. Envision a variable as a named storage
area containing an object.
Variables, reflecting the objects they contain, vary widely in both
size and type. Like stored computer files, variables are organized into
directories— “file folders” —that make 1t convenient to find them later.
Example: Determine the amount of memory (in bytes) currently
available to store HP 48 variables.
@ (WEWORY) MEN
Variables on the HP 48 are stored in SYSRAM—or on a plug-in card
in the case of the expandable HP 48 models. SYSRAM memory is like
a desktop computer’s Random-Access-Memory (RAM) except that it
is non-volatile—it isn’t erased when the HP 48 is turned off.
The figure below shows how the HP 48 divides up the SYSRAM and
the type of variables (in parentheses) stored in each section:
Partitions move depending on current allocation of memory
-
System Available Memory Stack Port 0
(system)
(local)
(global)
:
(port)
1
1
Program | User
1
1
1
1
1
1
1
1
Schematic view of SYSRAM in the HP 48
4-2 Understanding and Using Memory

HP 48G Series Specifications

General

Brand	HP
Model	48G Series
Category	Calculator
Language	English