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ASSEMBLES
When the Assembler is given control by the executive, it
proceeds to translate the Symbolic 8080 Assembly Language
(Source) program into 8080 machine
Assembler is a two pass assembler which operates on the
"current" file.
•
free format source input.
» . symbolic addressing, including forward references
and relative symbolic references.
•
complex expressions may be used as arguments.
« ■
self defining constants.
»
multiple constant forms.
«
up to 256 five character symbols.
»
reserved names for 8080 registers
*
ASCII character code generation
*
6 Pseudo Operations
The assembler translates those lines contained in the
current file into object code.
lowing the line "number
source code character position.
immediately -following the line number should normally be a
space.
Line numbers are not processed by the assembler;
they are merely reproduced on the listing.
The assembler will assemble a source program file com
posed of STATEMENTS, COMMENTS, and PSEUDO OPERATIONS.
During Pass 1, the assembler allocates all storage neces
sary for the translated program and defines the values of
all symbols used, by creating a symbol table.
allocated for the object code will begin at the byte in
dicated
by the 1st parameter in the original Executive
ASSM comm a n d .
During Pass 2, all expressions, symbols and ASCII constants
are evaluated to absolute values and are placed in allo
cated memory in the appropriate locations.
also produced during Pass 2, indicates exactly what data
is in each location of memory.
Features of the Assembler include:
(assembler directives)
The second character fol
is considered to be the first
Hence, the character
IMS AI 8080
Self-Contained System
Assembler
Revision 2
(object) code.
The
The storage
The listing,
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