8.24.3 PDP-11 Assembly Language Syntax
as
supports both DEC syntax and BSD syntax. The only difference is that in DEC syntax, a #
character is used to denote an immediate constants, while in BSD syntax the character for this purpose is $
.
eneral-purpose registers are named r0
through r7
. Mnemonic alternatives for r6
and r7
are sp
and pc
, respectively.
Floating-point registers are named ac0
through ac3
, or alternatively fr0
through fr3
.
Comments are started with a #
or a /
character, and extend to the end of the line. (FIXME: clash with immediates?)