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Assembly language instructions specify the program code that is to be assembled by the Ax51 assembler. The Ax51 assembler translates the assembly instructions in your program into machine code and stores the resulting code in an object file.

Assembly instructions have the following general format:

<[>label:<]> mnemonic <[>operand<]> <[>, operand<]> <[>/, operand<]> <[>; comment<]>


label symbol name that is assigned the address at which the instruction is located.
mnemonic is the ASCII text string that symbolically represents a machine language instruction.
operand is an argument that is required by the specified mnemonic.
comment is an optional description or explanation of the instruction. A comment may contain any text you wish. Comments are ignored by the assembler.

Refer to the x51 microcontrollers 8051 Instruction Set Manual, where they are listed by mnemonic and by machine language opcode, for more information about assembler instructions.

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