Visium Dependent Features
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Options
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The Visium assembler implements one machine-specific option:

-mtune=ARCH
     This option specifies the target architecture.  If an attempt is made to assemble an instruction that will not execute on the target architecture, the assembler will issue an error message.

     The following names are recognized: mcm24 mcm gr5 gr6

Syntax
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Special Characters
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Line comments are introduced either by the ! character or by the ; character appearing anywhere on a line.

A hash character (#) as the first character on a line also marks the start of a line comment, but in this case it could also be a logical line number directive (see Comments) or a preprocessor control command (see Preprocessing).

The Visium assembler does not currently support a line separator character.

Register Names
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Registers can be specified either by using their canonical mnemonic names or by using their alias if they have one, for example sp.

Opcodes
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All the standard opcodes of the architecture are implemented, along with the following three pseudo-instructions: cmp, cmpc, move.

In addition, the following two illegal opcodes are implemented and used by the simulation:

     stop    5-bit immediate, SourceA
     trace   5-bit immediate, SourceA