Legacy computer in embedded industial systems (Re: Oh Gods ...)

On 2026-08-23 04:32, Carlos E.R. wrote:
> On 2026-08-23 08:57, c186282 wrote:
>> On 8/22/26 18:35, Lawrence D’Oliveiro wrote:
>>> On Sat, 22 Aug 2026 08:36:42 -0400, TJ wrote:
>>>
>>>> It goes against the grain, for me at least, to send perfectly good
>>>> running hardware off to the recycler, just because it is
>>>> "experienced."
>>>
>>> CPU generations (and entire architectures) get dropped from the Linux
>>> kernel because they can’t find anybody to step forward and maintain
>>> the support for them.
>>>
>>> That is how they tell that there are so few instances of those
>>> particular kinds of hardware around, that essentially nobody cares
>>> about them any more.
>>
>>    Sad, but quite correct.
>>
>>    Really not much call to run Linux-ish stuff
>>    on a 386/486 these days. How many people
>>    still USE those old boards for ANYTHING ?
>>
>>    MAYBE a few "industrial" monitor/control
>>    systems ... but REALLY they oughtta upgrade.
>  > >    However SOME won't because it might cost a
>>    few dollars. They'll run the old hardware
>>    until it literally bursts into flames - and
>>    then be SCREWED for days/weeks/months. But,
>>    the bean-counters will TELL them they're
>>    saving SO much money, now .......
> 
> Industrial computers may have boards, like data acquisition boards, to 
> interface with motors and sensors (or cameras). If you upgrade the 
> computer, it comes with a new operating system, so their expensive 
> software does not run on it. The cards probably can not be plugged in, 
> so they also need replacing; the new boards will probably not be 
> compatible with the expensive software. So finally they need to recreate 
> the software (hopefully the company that created it still exists and has 
> the source files). And maybe there are a bunch of computers to replace.
> 
> The price is no longer minor.

What you have to do is make sure you have one or two backup hardware 
packages, because when the computer breaks, you won't be able to buy one 
that works. (Just try to find a motherboard with ISA slots today!)
And with custom plugin boards, it is kinda too late to have them fabbed 
when the system is already down. And fire it up once a year to make sure 
it still runs.

That may not guarantee that you can recover, but it vastly increases 
your chances.

And when you put the reserve system into service, it is time to expedite 
developing a replacement!

For PC systems, the big hurdle is that old 16-bit systems allowed
programs to do I/O to ISA bus peripherals without kernel programming, 
device drivers and OS hooks. When you "modernize" that ability is lost, 
and you have to rebuild with much more complicated programming.

-- 
Lars Poulsen - an old geek in Santa Barbara, California