.MODEL Directive
.MODEL directive determines several important characteristics of a program: its memory model type, procedure naming scheme, and parameter passing convention.
The syntax of the .MODEL directive is
.MODEL memorymodel [, modeloptions]For example,
.model flat, C .model flat, STDCALLMemory Model
memorymodel field can be one the the models described in the table.
| Model | Description |
|---|---|
Tiny |
A single segment, containing both code and data. |
Small |
One code segment and one data segment. |
Medium |
Multiple code segments and a single data segment. |
Compact |
One code segment and multiple data segments. |
Large |
Multiple code and data segments. |
Huge |
Same as the large model, except that individual data items may be larger than a single segment. |
Flat |
Protected mode. Uses 32-bit offsets for code and data. |
modeloptions field includes a language specifier, which determines calling and naming conventions for procedures and public symbols.
There are two kinds of language specifier options:
C, BASIC, FORTRAN, and PASCAL specifiers enable assembly language programmers to create procedure that are compatible with these languages.
SYSCALL and STDCALL specifiers are variations on the other language specifiers.