MC68030RC33C Freescale Semiconductor, MC68030RC33C Datasheet - Page 41

• Manufacturer Part Number: MC68030RC33C
• Description: IC MPU 32BIT ENHANCED 128-PGA
• Manufacturer: Freescale Semiconductor

Specifications of MC68030RC33C

• Processor Type: M680x0 32-Bit
• Speed: 33MHz
• Voltage: 5V
• Mounting Type: Surface Mount
• Package / Case: 128-PGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -

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1.6.1 Virtual M e m o r y
1-12
1.6 V IR TU AL M E M O R Y A N D VIRTUAL M A C H I N E CONCEPTS
to access devices that are not physically present in the system, such as tape
A system that supports virtual memory has a limited amount of high-speed
tains an image of a much larger virtual memory on a secondary storage
The MC68030 uses instruction continuation to support virtual memory. When
the bus error handler has completed execution, it returns control to the
The full addressing range of the MC68030 is 4 Gbytes (4,294,967,296 bytes)
4 Gbytes of memory available to each user program by using virtual memory
techniques.
amount of memory available, when the physical memory actually present is
drives, disk drives, printers, terminals, and so forth. With proper software
emulation, a physical system can appear to be any other M68000 computer
system to a user program, and the program can be given full access to all
of the resources of that emulated system. Such an emulated system is called
a virtual machine.
physical memory that can be accessed directly by the processor and main-
device such as a large-capacity disk drive. When the processor attempts to
access a location in the virtual memory map that is not resident in physical
memory, a page fault occurs. The access to that location is temporarily sus-
placed in physical memory. The suspended access is then either restarted
or continued.
a bus cycle is terminated with a bus error, the microprocessor suspends the
current instruction and executes the virtual memory bus error handler. When
in each of eight address spaces. Even though most systems implement a
smaller physical memory, the system can be made to appear to have a full
In a virtual memory system, a user program can be written as if it has a large
much smaller. Similarly, a system can be designed to allow user programs
pended while the necessary data is fetched from secondary storage and
program that was executing when the error was detected, reruns the faulted
bus cycle (when required), and continues the suspended instruction.
MC68030 USER'S MANUAL
MOTOROLA