Harvard vs. Von Neumann Architecture

This article compares Harvard and Von Neumann architectures, highlighting the key differences between these two CPU architectures commonly used in Digital Signal Processors (DSPs).

Harvard Architecture

Figure 1 illustrates the Harvard architecture. Here are its defining characteristics:

• It utilizes separate memories for storing data and instructions (code).
• It has two distinct sets of address/data buses connecting the CPU and memory.
• The Harvard architecture allows for simultaneous fetching of data and instructions from memory.
• Many modern DSPs leverage the Harvard architecture for efficient data streaming, offering greater and more predictable memory bandwidth.

Examples of Microprocessors Based on Harvard Architecture:

• ARM9
• SHARC (DSP)

Von Neumann Architecture

Figure 2 illustrates the Von Neumann architecture. Its key features include:

• It uses a single, shared memory to store both data and instructions.
• It employs a single set of address/data buses for communication between the CPU and memory.

Examples of Microprocessors Based on Von Neumann Architecture:

• ARM7
• Pentium