#: 8938 S12/OS9/68000 (OSK)
    29-Dec-90  20:07:02
Sb: #8930-#68000 ASM Language
Fm: Jack Crenshaw 72325,1327
To: William Phelps 75100,265 (X)

William, I'm only just getting started in OS9, and my "baseline" system is
SK*DOS, until something better comes along.  I posted the message here because,
OS9 or no OS9, this is the only forum where people talk much about 68000's.

Re the PIC:  That would be best.  SK*DOS (and OS9) requires it.  Which sort of
means that the assembler shouldn't make you do anything special to get it. 
There _ARE_ some implementation issues that I haven't worked out yet. Example: 
You can address variables PC-relative, but then if you're using OS9 you can
also address them base A6.  Since the fundamental nature of the assembler is to
let the programmer do anything the chip will support, I suppose that you can't
assume anything, or impose any coding style.  Still, there should be some easy
way to tell the assembler what you want, instead of having to write things like
foo-base(a6) all the time.  I've thought of having pseudo-ops something like

       BASE A6 = OFFSET
       BASE PC
   or  BASE ABSOLUTE

so that once declared, you could reference data from that base.  (Don't know
WHAT you do if you need more than one!)  As for control references, I'd like to
see BRA's and BSR's generated by default, with some kind of mechanism for
dealing with things out of range and/or external.

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