[Coco] lwtools assembler difference

[Dave Philipsen]

I'm not actually using the lwtools assembler. I'm just comparing the 
output of the stock OS9 assembler to a dump of the Boot module that I 
obtained from the OS9Boot file that was in a disk image that was given 
to me.  Perhaps whomever compiled that disk image disabled the pragma.  
Thanks for the explanation though.

Dave Philipsen


On , Tormod Volden wrote:
> On Tue, Sep 1, 2015 at 9:16 PM, Dave Philipsen wrote:
>> Well, in my comparison of the code generated by the lwtools assembler 
>> and
>> the stock OS9 assembler I have found a quirk of the lwtools assembler. 
>>  I
>> won't call it an error because it appears that the outcome is not 
>> affected
>> and it seems to be a minor thing.  On every other assembler I've used
>> including AS6809, CSC6809, and the stock OS9 assembler the following
>> assembly source:
>> 
>> ldb  ,x
>>  or
>> ldb 0,x
>> 
>> is assembled in machine code as:
>> 
>> E6 84
>> 
>> which is the indexed addressing mode with no offset
>> However, the lwtools assembler (evidently) assembles in machine code 
>> as:
>> 
>> E6 00
>> 
>> which is the indexed addressing mode with a 5-bit offset with the 
>> offset
>> being zero.
> 
> Please read about the "index0tonone" pragma in the manual
> http://lwtools.projects.l-w.ca/manual/manual.html#AEN628
> 
> Is it possible that you have disabled this pragma?
> 
> Regards,
> Tormod
> 
>> 
>> I dont have a copy of EDTASM anymore so I can't say how it would 
>> assemble
>> it.  This just seems to be the case of a smart assembler which 
>> determines
>> the given offset to be zero and thus translates it as a "no offset" 
>> postbyte
>> as opposed to a "5-bit offset" postbyte.
>> 
>> Dave Philipsen