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8051 Instruction Set Manual

The 8051 Instruction Set Manual explains the standard 8051 instructions. The 8051 Instruction Set is supported by the Keil Ax51 Macro Assembler and the in-line Assembler of the Keil Cx51 Compiler.

This manual contains the following chapters:

  • Architecture Overview describes the memory layout and CPU registers of several 8051 variants.
  • Opcodes lists all opcodes ordered by opcode HEX value.
  • Instructions describes all of the 8051 instructions.

Revision History

  • January 2011: DA instruction adapted
  • April 2007: Added Graphics
  • September 2005: First draft

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