A86 (software)
Encyclopedia
A86 is a compact commercial assembler developed for the Intel x86 family of microprocessor
s by Eric Isaacson. The assembler can directly produce a Windows
/DOS
compatible .COM
or .OBJ
file from a simple text source file. It uses a slightly simpler syntax
for source code than that used by other assemblers, and it is optimize
d for maximum speed at both assembly and run times. It comes with a debugger
, D86.
A86/D86 target 16-bit
x86 platforms. The companion products A386 and D386 are designed for 32-bit
platforms.
The A86 assembler was the first programming tool to automatically embed a "signature" into the code which it generated. Through its choice of instructions (many of which are functionally equivalent), it was possible to distinguish between registered and unregistered versions of the assembler, although access to the source code was required.
Microprocessor
A microprocessor incorporates the functions of a computer's central processing unit on a single integrated circuit, or at most a few integrated circuits. It is a multipurpose, programmable device that accepts digital data as input, processes it according to instructions stored in its memory, and...
s by Eric Isaacson. The assembler can directly produce a Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
/DOS
DOS
DOS, short for "Disk Operating System", is an acronym for several closely related operating systems that dominated the IBM PC compatible market between 1981 and 1995, or until about 2000 if one includes the partially DOS-based Microsoft Windows versions 95, 98, and Millennium Edition.Related...
compatible .COM
.com
The domain name com is a generic top-level domain in the Domain Name System of the Internet. Its name is derived from commercial, indicating its original intended purpose for domains registered by commercial organizations...
or .OBJ
Object file
An object file is a file containing relocatable format machine code that is usually not directly executable. Object files are produced by an assembler, compiler, or other language translator, and used as input to the linker....
file from a simple text source file. It uses a slightly simpler syntax
Syntax of programming languages
In computer science, the syntax of a programming language is the set of rules that define the combinations of symbols that are considered to be correctly structured programs in that language. The syntax of a language defines its surface form...
for source code than that used by other assemblers, and it is optimize
Optimization (computer science)
In computer science, program optimization or software optimization is the process of modifying a software system to make some aspect of it work more efficiently or use fewer resources...
d for maximum speed at both assembly and run times. It comes with a debugger
Debugger
A debugger or debugging tool is a computer program that is used to test and debug other programs . The code to be examined might alternatively be running on an instruction set simulator , a technique that allows great power in its ability to halt when specific conditions are encountered but which...
, D86.
A86/D86 target 16-bit
16-bit
-16-bit architecture:The HP BPC, introduced in 1975, was the world's first 16-bit microprocessor. Prominent 16-bit processors include the PDP-11, Intel 8086, Intel 80286 and the WDC 65C816. The Intel 8088 was program-compatible with the Intel 8086, and was 16-bit in that its registers were 16...
x86 platforms. The companion products A386 and D386 are designed for 32-bit
32-bit
The range of integer values that can be stored in 32 bits is 0 through 4,294,967,295. Hence, a processor with 32-bit memory addresses can directly access 4 GB of byte-addressable memory....
platforms.
The A86 assembler was the first programming tool to automatically embed a "signature" into the code which it generated. Through its choice of instructions (many of which are functionally equivalent), it was possible to distinguish between registered and unregistered versions of the assembler, although access to the source code was required.