US 2003/0229756 A1 · Virtual expansion of program RAM size

Abstract

A method and apparatus for virtually expanding the rapid-access memory space of a device employing time-critical software modules and having various modes of operation. Each of the modes of operation of the device is identified. For each mode of operation, the time-critical software modules used during the mode are identified. The software modules used during all modes of operation are permanently stored in rapid-access memory. However, a software module that is used only during a particular mode of operation is loaded into the rapid-access memory unit only upon entry into the mode of operation in which it is used. The software module is loaded into a region of memory occupied by another software module not utilized during the particular mode of operation being entered.

Claims24

Dependent claims

In a data storage device including a rapid-access memory unit, a slow-access memory unit, a read-only memory unit, and a microprocessor for executing software instructions stored upon the rapid-access and slow-access memory units, a method for loading a first software unit used during a first mode of operation from the slow-access memory unit into the rapid-access memory unit, the method comprising:

(a) receiving a command from a host;
(b) determining whether the command requires access to the first software unit;
and
(c) loading the first software unit from the slow-access memory into an address range in the fast access memory occupied by a second software unit not used during the first mode of operation, upon an affirmative determination in step (b).

1 more element

Dependencies are inferred from the claim text.

Virtual expansion of program RAM size

Life of this patent

Virtual expansion of program RAM size

Life of this patent

Abstract

Claims24