Re: Early-2014 Macbook Air and Linux Mint Cinnamon

On 26/06/2026 09:55, Carlos E. R. wrote:
> On 2026-06-26 01:21, Lawrence D’Oliveiro wrote:
>> On Thu, 25 Jun 2026 11:26:47 +0200, Carlos E. R. wrote:
>>
>>> On 2026-06-25 03:13, Lawrence D’Oliveiro wrote:
>>>>
>>>> On Wed, 24 Jun 2026 12:07:47 +0200, Carlos E. R. wrote:
>>>>
>>>>> On 2026-06-24 03:30, Lawrence D’Oliveiro wrote:
>>>>>>
>>>>>> On Sun, 21 Jun 2026 09:35:34 +0200, Marc Haber wrote:
>>>>>>
>>>>>>> This thread for some reason gave me 40 year old 6502 vibes,
>>>>>>> where the only fully usable register is called the accumulator.
>>>>>>
>>>>>> “Accumulator” was a common synonym for “register” in the early
>>>>>> days.
>>>>>>
>>>>>> E.g. I think the PDP-10 had 4 accumulators. Their
>>>>>> assembly-language names were AC0, AC1, AC2, AC3.
>>>>>
>>>>> An accumulator is not a register. It is different, you can do
>>>>> operations on it.
>>>>
>>>> Which one? What’s the point of having one where “you cannot do
>>>> operations on it”?
>>>
>>> It just was so. The ALU wrote to the accumulator, not to other
>>> registers.
>>
>> There was also an older usage where “register” was a synonym for
>> “memory location”. You’re not using it in that sense, are you?
> 
> Nono, just some storage inside the CPU.
> 
> 
No. In some architectures its in memory

> Later processors, like the 68000, could receive results on any register.
> 
And more importantly some other CPUs did not really make a distinction 
between RAM and onboard registers.

ISTR that Turing's original theoretical machine only had, in effect, an 
instruction pointer.

It's perfectly possible to construct a CPU that has only one 'register' 
- a frame pointer pointing to a frame in which all the RAM based 
registers are to be found. Arguably even this is not necessary, as you 
could reserve a fixed piece of RAM to contain that data.

It's merely a matter of speed. And modern CPUS map huge areas of RAM 
into cache 'registers' anyway. The distinction is very blurred

It represents te perfect dichotomy between the idealisations of the 
'computer scientist' and the fundamental realities of engineering a 
blisteringly fast machine to process serial intsructions




-- 
The urge to save humanity is almost always a false front for the urge to 
rule.
– H. L. Mencken, American journalist, 1880-1956