Reference:http://www.mikroe.com/products/view/267/architecture-and-programming-of-8051-mcu-s/

• Chapter 1: Introduction to Microcontrollers
• Chapter 2: 8051 Microcontroller Architecture
• Chapter 3: The 8051 Instruction Set
• Chapter 4: AT89S8253 Microcontroller
• Chapter 5: Assembly Language
• Chapter 6: Examples
• Chapter 7: Development systems