I need an explanation about the term "opcode". I have found this :
An opcode is binary or hex value of the machine instruction in the cpu instruction set.
If I understand correctly the definition, for instance :
6A 03 push 3
6A is the opcode et 03 the operand. But in several posts on different forums, people talk about 03 as if it was an opcode (for instance this
Here, 3 is an immediate because it's included directly as part of the opcode (in the second byte).
Does 03 is an opcode and an operand?