Panasonic MN1030 user manual Machine language instruction statements, Directive statements

Chapter 7 Type of Source Statements

7.3Machine Language Instruction Statements and Directive Statements

Machine language instruction statements

Machine language instructions are instructions that the microprocessor directly executes on its own hardware. Each machine language code has a corresponding mnemonic.

Machine language instruction statements are statements that code these mnemonics. The assembler will convert them into machine language code (called object code). After the program has been converted to ROM, these statements will be executed by the microprocessor.

The instructions have the following features.

•Memory-oriented instruction set (all calculations performed throughout memory)

•Single and double-operand instructions

•Minimized instruction set and instruction codes

•Six addressing formats

The example below shows machine language instruction statements.

mov	0xff, D0
mov	data1, A0
mov	D0, (A0)
add	1, D0
rts

Directive statements

Directive statements are not converted to machine language code. Within programs they specify assem- bler attributes to modify program structure and addresses, select radices, define constants, and control list file style.

The example below shows directive statements.

	global	save
CONST	equ	0x12
_TEXT	section	CODE, PUBLIC, 1
	org	100
MESG	dc	‘S’
	end

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