HP 49g Graphing Calculator - Manual (Page 102)

Chapter 11
Memory
This section describes the memory structure of tire HP 49G. It describes
how to create backup objects of data that you want to save, and how to
use libraries to add functionality to the calculator.
How memory is structured
The HP 49G contains a total of 2.5 Mb of memory. Of this memory:
• 1 Mb is used to hold the operating system.
® 1.5 Mb is used for performing the operations that you specify, and for
storing data that you want to keep. The HP 49G needs a minimum of
approximately 200 bytes free in order to perform operations.
The memory of the HP49G is divided into 4 areas:
® The Home directory
® Port 0, labelled IRAM in File Manager
The Home directory and port 0 share the same area of memory. That is,
the more data you store in the HOME directory, the less data you can
store in port 0 and vice versa. The total size of objects in these two
areas carmot exceed 241 Kb.
• Port 1, labelled ERAM in File Manager
Port 1 can contain up to 255KB of data.
• Port 2, labelled FLASH in File Manager
Port 2 can contain up to 1085KB of data.
The Home directory, port 0 and port 1 are part of RAM. Leaving the
calculator without batteries can cause RAM to loose its data. Wlren
changirrg batteries, ensure that you do rrot leave the calculator without
batteries for longer than two minutes.
The data in port 2 is stored in the Flash ROM. This data does irot depend
on batteries. It is preserved even if you leave the calculator without
batteries for a long time.
Memory Page 11-1