MOTOROLA
MC68341 USER’S MANUAL
5- 1
SECTION 5
CPU32
The CPU32, the first-generation instruction processing module of the M68300 family, is
based on the industry-standard MC68000 core processor. It has many features of the
MC68010 and MC68020 as well as unique features suited for high-performance processor
applications. The CPU32 provides a significant performance increase over the MC68000
CPU, yet maintains source-code and binary-code compatibility with the M68000 family.
5.1 OVERVIEW
The CPU32 is designed to interface to the intermodule bus (IMB), allowing interaction with
other IMB submodules. In this manner, integrated processors can be developed that
contain useful peripherals on chip. This integration provides high-speed accesses among
the IMB submodules, increasing system performance.
Another advantage of the CPU32 is low power consumption. The CPU32 is implemented
in high-speed complementary metal-oxide semiconductor (HCMOS) technology, providing
low power use during normal operation. During periods of inactivity, the low-power stop
(LPSTOP) instruction can be executed, shutting down the CPU32 and other IMB modules,
greatly reducing power consumption.
Ease of programming is an important consideration when using an integrated processor.
The CPU32 instruction format reflects a predominant register-memory interaction
philosophy. All data resources are available to operations that require them. The
programming model includes eight multifunction data registers and seven general-purpose
addressing registers. The data registers support 8-bit (byte), 16-bit (word), and 32-bit
(long-word) operand lengths for all operations. Address manipulation is supported by word
and long-word operations. Although the program counter (PC) and stack pointers (SP) are
special-purpose registers, they are also available for most data addressing activities. Ease
of program checking and diagnosis is enhanced by trace and trap capabilities at the
instruction level.
As processor applications become more complex and programs become larger, high-level
languages (HLLs) will become the system designer's choice in programming languages.
HLLs aid in the rapid development of complex algorithms with less error and are readily
portable. The CPU32 instruction set efficiently supports HLLs.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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