[Info-vax] Assembly languages, was: Re: OT: PDP-11 history in arstechnica

[Simon Clubley]

On 2022-03-16, Rich Alderson <news at alderson.users.panix.com> wrote:
>
> ALL the PDP-10 mnemonics for instructions which access memory have the same
> form (taking MOVE as a canonical example):
>
> 	MOVE	load accumulator with contents of memory at effective address
> 	MOVEI	load accumulator with immediate effective address calculation
> 	MOVES	load accumulator with swapped halfwords of contents of memory
> 		at effective address
> 	MOVEM	store accumulator into memory at effective address
>
> Look at the last character of the instruction.  You don't even have to remember
> the difference between "load" and "store".
>

Doesn't anyone else find it strange that the mnemonic across all
architectures is some variant of MOVE or MOV instead of COPY or CPY ?

After all, you are not destroying the contents at the original
location/register when you copy it to the target location/register. :-)

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
Walking destinations on a map are further away than they appear.