Mnemonics and Operands

An assembly code instruction (statement) consists of a mnemonic (pronounced "nih-MON-ick"), and between zero and three operands.  For a logical or arithmetic mnemonic with two operands, the right operand is the source and the left operand is the destination.  In general, 80x86 assembly code instructions takes the following form:

[ASM|!] mnemonic  destination, source

For example:

! MOV EAX, 1


In the examples above, the keywords MOV and ADD are the mnemonics, EAX is the destination operand, and 1 and EBX are the source operands.

In the first line, the value 1 is "moved" into the EAX operand (register).  In BASIC code, this works similarly to the statement A = 1.  The second example adds the value in EBX to the value in EAX and stores the result in EAX.  In BASIC code, this works similarly to A = A + B.


See Also

The Inline Assembler

Using assembly-language in your code

Opcodes and Mnemonics