EZ-USB Datasheet, PDF (275/334 Pages) Cypress Semiconductor – The EZ-USB USB Integrated Circuit

Appendix A: 8051 Introduction
A.1 Introduction
The EZ-USB contains an 8051 core that is binary compatible with the industry standard 8051
instruction set. This appendix provides an overview of the 8051 core features. the topics are:
• New 8051 Features
• Performance Overview
• Software Compatibility
• 803x/805x Feature Comparison
• 8051/DS80C320 Differences
A.2 8051 Features
The 8051 core provides the following design features and enhancements to the standard 8051
micro-controller:
• Compatible with industry standard 803x/805x:
- Standard 8051 instruction set
- Two full-duplex serial ports
- Three timers
• High speed architecture:
- 4 clocks/instruction cycle
- 2.5X average improvement in instruction execution time over the standard 8051
- Runs DC to 25-MHz clock
- Wasted bus cycles eliminated
- Dual data pointers
• 256 Bytes internal data RAM
• High-speed external memory interface with 16-bit address bus
• Variable length MOVX to access fast/slow RAM peripherals
• Fully static synchronous design
• Supports industry standard compilers, assemblers, emulators, and ROM monitors
EZ-USB TRM v1.9
Appendix A: 8051 Introduction
A-1