Writing ASM-Files

Here you find a description on how to write Assembler - Files:

 

The Assembler - Files can be written with any Text - Editor you want to use.

But for Simulating them with MikroOne - Simulator you should watch some Rules:

 

An ASM-File contains of:

·         Commands

·         Comments

·         Labels

·         Equations

 

Commands

To compile an ASM-File without errors all containing commands must be with right syntax.

If not the Compiler will tell you where he found errors.

If you need information on the Commands please see the  Command Overview.

 

Comments

Comments always have to start with an Semicolon (;).

You can place them alone in a row or behind a Command.

 

Labels

Label are used to tell jump - Commands where to go.

They can be placed alone in a row, or in front of a Command.

They have to end with a Colon.

You are able to load the address value of a Label with the Command LDL to a register.

This is very useful for example when using Interrupt Service Routines,

because you do not need to calculate the addresses by yourself.

As you only can use LDL, the addresses can not be larger than 255.

If they are larger, only the Low-Byte is used.

So keep in mind that your Labels are placed in the range from 0 to 255.

 

Values

You can write values in your ASM-File in two different ways:

·         Decimal

·         Hexadecimal

·         Binary

If you use decimal Values you just write the number you want to have.

Example:

LDH R[2], 20

When using Hexadecimal Values you have to write a "$" in front of the number.

Example:

LDH R[2], $10

If you want to use Binary Values you have to use the “%” prefix.

Example:

LDL R[2],%0100 ;This loads the Value 4 into Register 2.

 

Equations

You are also able to use Equations in your ASM-File.

Equations are Preprocessor Directives and have to be at the beginning of an ASM-File.

Only Comments can occure before them.

Equations can be Values, like described above or even entire Commands.

 

To create Equations you have to write:

 

            Name EQU Value

Example of an ASM-File containing Equations:

            ;This is a comment

EQU1 EQU $FF

            COM1 EQU ADD R[2],R[3],R[4]

           

LDH R[3],EQU1

            COM1

Note

If you click the Open-File Button while writing an ASM-File, you get asked if you want to save the current File.

If you cancel and after that do not open a File, the code you already have written is lost.