INTRODUCTION

The superscalar MC68060 represents a new line of Motorola microprocessor products. The first generation of the M68060 product line consists of the MC68060, MC68LC060, and MC68EC060. All three microprocessors offer superscalar integer performance of over 100 MIPS at 66 MHz. The MC68060 comes fully equipped with both a floating-point unit (FPU) and a memory management unit (MMU) for high-performance embedded control and desktop applications. For cost-sensitive embedded control and desktop applications where an MMU is required, but the additional cost of a FPU is not justified, the MC68LC060 offers high-performance at a low cost. Specifically designed for low-cost embedded control applications, the MC68EC060 eliminates both the FPU and MMU, permitting designers to leverage MC68060 performance while avoiding the cost of unnecessary features. Throughout this product brief, all references to the MC68060 also refer to the MC68LC060 and the MC68EC060, unless otherwise noted.

FEATURES

The main features of the MC68060 are as follows:

• 1.6–1.7 Times the MC68040 Performance at the Same Clock Rate with Existing Compliers. 3.2–3.4 Times the Performance of a 25 MHZ MC68040.

• Harvard Architecture with Independent, Decoupled Fetch and Execution Pipelines.

• Branch Prediction Logic with a 256-Entry, 4-Way Set-Associative, Virtual-Mapped Branch Cache for Improved Branch Instruction Performance.

• A Superscalar Pipeline and Dual Integer Execution Units Achieving Simultaneous, but not Out-of-Order Instruction Execution.

• An IEEE Standard, MC68040- and MC68881-/MC68882-Compatible FPU.

• An MC68040-Compatible Paged Memory Management Unit with Dual 64-Entry Address Translation Caches

• Dual 8-Kbyte Caches (Instruction Cache and Data Cache)

• A Flexible, High-Bandwidth Synchronous Bus Interface

• User Object-Code Compatible with All Earlier M68000 Microprocessors