CHAPTER
21

~SEMBLER

CONTROLS

Introduction to Assembler Controls

Assembler controls allow you
to
specify the
input!
output files or devices to be used
by
the assembler
and
whether list
or
object files (or portions
of
these files) are to be
generated by the assembler. Controls
can
be specified
at
two levels:
•
In
commands specified
at
assembly time
• As control lines embedded throughout your source file
The latter allows selective control over sections
of
your program. For example, you
might want to suppress the assembly listing for certain sections
of
your program, or
to
cause page ejects
at
specific places.
Primary and General Controls
Controls are classified as primary
and
general. Both classes
of
controls can be set
when the assembler
is
run
or in source file control lines. However, source file control
lines containing primary controls must be inserted before the first line
of
comments
or
source code. General controls can be respecified
at
any time.
The
ISIS-II assembler allows primary controls
to
be
specified only once. This applies
to
controls specified in assembly-time command lines,
to
control lines embedded in
your source code,
or
combinations
of
the two.
Specifying Controls
Controls can be specified using either upper-case
or
lower-case characters.
If
a control
is
specified incorrectly in
an
assembly-time command, the entire com-
mand
is
ignored
and
must be reentered.
If
a control is specified incorrectly in a source code control line, the incorrect control
and
all controls following it in the line
are
ignored.
Summary
of
Controls
The
following list shows the controls available, their basic functions, and whether
they are primary
or
general
(PIG).
Default controls are italicized. The remainder
of
this chapter describes each control in greater detail.
Control
PIG
Function Area
OBJECT INOOBJECT P Object File
OEBUGINOOEBUG P Object File
PRINT INOPRINT P Assembly Listing
CONO INOCONO G Assembly Listing
LlSTINOLIST
G Assembly Listing
SYMBOLS INOSYMBOLS P Assembly Listing
XREF
INOXREF P Cross-Reference Listing
PAGING INOPAGING P
listing
Format
2-1