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VAX Addressing Modes

Assembler	Comment
#<expr;>	The operand is a read only constant = <expr;>.; (Compiles to (PC)+ or a literal. )
<expr;>	The <expr;> specifies the memory address of the operand. (PC relative. Assembles to <expr;> - current_location (PC) )
@#<expr;>	The <expr;> specifies the memory address of the operand. (Absolute. Has the same effect as <expr;> but assembles to @(PC)+ )
@<expr;>	The <expr;> specifies the address of the address of the operand. (Assembles to @<expr;> - current_location (PC) )
Rn	The operand is the register contents.
(Rn)	The operand is at the address specified in the register.
-(Rn)	The Register contents are decremented by the size of the operand type before being used as the address the operand.
(Rn)+	The Register contents are incremented by the size of the operand type after being used as the address the operand.
@(Rn)+	The Register contents is incremented by 4 after being used to obtain the address of the address of the operand.
<expr;>(Rn)	The operand is at the address specified by the <expr;> + the register contents.
@<expr;>(Rn)	The address of the address of the operand is specified by the <expr;> + register contents .
Indexed Modes	Next Page

<expr;> is an expression as described (see XXX).
An <expr;> is evaluated at assembly time.
Rn and Rx are any registers and may be the same register (be careful if they you do this).
The assembler recognises the UNIX;
But MacVAX will always display these in the VMS form used above.

Assembler