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I don't get this. What is the difference of allowed operand formats
in the register operands in LA and the numbers in the AL.4 constant ?

Or the displacement in LA and the displacement in the Y address constant?

Kind regards

Bernd


Am 21.12.2013 22:27, schrieb I.W.:
> As the OP, the version leveraging a similar instruction is infinitely more
> useful to me as it allows the assembler to deal with the multitude of operand
> formats rather than making me have to.
>
> i
>
> ------ Original Message ------
> Received: 04:16 PM COT, 12/21/2013
> From: M.B.
> To: ASSEMBLER-LIST@LISTSERV.UGA.EDU
> Subject: Re: macros to implement opcodes
>
>> Stepping back from everything that's already been suggested, when I wrote
>> this from scratch, I used something simpler:
>>
>>          MACRO ,
>> &LABEL   DIAG  &RX,&RY,&DISP
>> &LABEL   DC    0H,X'83',AL.4(&RX,&RY),Y(&DISP)
>>          MEND  ,
>>
>> The overwriting of another instruction seems unneccesarily complex.  I'm
>> guessing that the intent was to allow the assembler to produce register
>> cross-reference entries, but some Diags use only Rx and not Ry, some use an
>> implied Rx+1 and Ry+1, etc., which means that (the lack of) any
>> cross-reference entries can't be trusted anyway.  If the overwriting was
>> done for another reason, hopefully someone will let me know.
>>
>> - mb
>>