org	0
nulovani:
	mov	r2,#0	
	mov	r3,#0	
	call	zobraz
	jmp	klavesnice

prog:	inc 	r2	
	cjne	r2,#7,aaa
	mov	r2,#1
aaa:	jmp	klavesnice

klavesnice:
	jnb	p1.4, start
	jnb	p1.5,nulovani
	call	zobraz
	jmp	klavesnice

start:	jnb	p1.3,prog		
	jnb	p1.5,nulovani
	inc	r3		
	cjne	r3,#50,pokracovat	
	mov	r3,#1		
pokracovat:
	call	zobraz
	jmp	start

zobraz:
	mov	a,r2	
	orl	a,#00110000b
	mov	p3,a
	mov	p3,#00101111b	
	mov	a,r3	
	mov	b,#10
	div	ab
	orl	a,#00010000b
	mov	p3,a
	mov	a,b
	orl	a,#00000000b
	mov	p3,a
	ret

	end
		   

Assembly Online Compiler

Write, Run & Share Assembly code online using OneCompiler's Assembly online compiler for free. It's one of the robust, feature-rich online compilers for Assembly language. Getting started with the OneCompiler's Assembly compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as Assembly and start coding.

About Assembly

Assembly language(asm) is a low-level programming language, where the language instructions will be more similar to machine code instructions.

Every assembler may have it's own assembly language designed for a specific computers or an operating system.

Assembly language requires less execution time and memory. It is more helful for direct hardware manipulation, real-time critical applications. It is used in device drivers, low-level embedded systems etc.

Syntax help

Assembly language usually consists of three sections,

  1. Data section

    To initialize variables and constants, buffer size these values doesn't change at runtime.

  2. bss section

    To declare variables

  3. text section

    _start specifies the starting of this section where the actually code is written.

Variables

There are various define directives to allocate space for variables for both initialized and uninitialized data.

1. To allocate storage space to Initialized data

Syntax

variable-name    define-directive    initial-value 
Define DirectiveDescriptionAllocated Space
DBDefine Byte1 byte
DWDefine Word2 bytes
DDDefine Doubleword4 bytes
DQDefine Quadword8 bytes
DTDefine Ten Bytes10 bytes

2. To allocate storage space to un-initialized data

Define DirectiveDescription
RESBReserve a Byte
RESWReserve a Word
RESDReserve a Doubleword
RESQReserve a Quadword
RESTReserve a Ten Bytes

Constants

Constants can be defined using

1. equ

  • To define numeric constants
CONSTANT_NAME EQU regular-exp or value

2. %assign

  • To define numeric constants.
%assign constant_name value

3. %define

  • To define numeric or string constants.
%define constant_name value

Loops

Loops are used to iterate a set of statements for a specific number of times.

mov ECX,n
L1:
;<loop body>
loop L1

where n specifies the no of times loops should iterate.

Procedures

Procedure is a sub-routine which contains set of statements. Usually procedures are written when multiple calls are required to same set of statements which increases re-usuability and modularity.

procedure_name:
   ;procedure body
   ret