OK thanks :)

Joe

On Sat, Oct 23, 2021 at 7:37 PM David Spiegel <[email protected]>
wrote:

> Hi Joe,
> You are forgetting that '=H' creates a storage area of a half-byte,
> which is addressed by the RX Instruction.
> Here is what happens:
>    Active Usings: None
>    Loc  Object Code    Addr1 Addr2  Stmt   Source
> Statement                                  HLASM R6.0  2021/10/23 20.37
> 000000                00000 0000A     1 TEST CSECT
>                   R:F  00000           2          USING *,15
> 000000 4820 F008            00008     3          LH 2,=H'-5'
>                                        4 END
> 000008 FFFB                           5                =H'-5'
>
> Regards,
> David
>
> On 2021-10-23 20:18, Joe Monk wrote:
> > OK then explain this:
> >
> > LH is an RX format instruction. What are the D, X and B values if the
> > second operand is simply =H'-5'?
> >
> > Joe
> >
> > On Sat, Oct 23, 2021 at 6:49 PM Paul Gilmartin <
> > [email protected]> wrote:
> >
> >> On Sat, 23 Oct 2021 18:36:54 -0500, Joe Monk wrote:
> >>
> >>> LH is an RX instruction.
> >>>
> >>> So, LH 3,=H'-5' would give an addressing exception, no? Because the
> second
> >>> operand is treated as coming from storage? So that would be a negative
> >>> address?
> >>>
> >> No.
> >>
> >>> If you said LH 3,0(=H'-5',2), that would give you ITEM+5?
> >>>
> >> You have a bad use-versus-mention conflation.  The value of an
> >> object is not the address of that object.
> >> <
> https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FUse%25E2%2580%2593mention_distinction&amp;data=04%7C01%7C%7C5e84fc92bdc04108c95108d99683ec8e%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637706315699635719%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=vdAJBoVajwyo3xC%2FjxfrXB94px9%2FVKJNgGIexK%2Fc2WA%3D&amp;reserved=0
> >
> >>
> >>
> >>> On Sat, Oct 23, 2021 at 6:01 PM Bernd Oppolzer wrote:
> >>>> LA   2,ITEM+10
> >>>> LH   3,=H'-5'
> >>>> LA   2,0(2,3)
> >>>>
> >>>> will put the address ITEM+5 in register 2, at least in AMODE 24/31?
> >>>>
> >> I agree.
> >>
> >> -- gil
> >>
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