as: VAX-operands
9.49.6 VAX Operands
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The immediate character is '$' for Unix compatibility, not '#' as DEC
writes it.
The indirect character is '*' for Unix compatibility, not '@' as DEC
writes it.
The displacement sizing character is '`' (an accent grave) for Unix
compatibility, not '^' as DEC writes it. The letter preceding '`' may
have either case. 'G' is not understood, but all other letters ('b i l
s w') are understood.
Register names understood are 'r0 r1 r2 ... r15 ap fp sp pc'. Upper
and lower case letters are equivalent.
For instance
tstb *w`$4(r5)
Any expression is permitted in an operand. Operands are comma
separated.