Re: LOTS of US Water Plants Hit by Hacks

On 05/08/2026 07:14, rbowman wrote:
> On Wed, 5 Aug 2026 00:58:46 -0400, c186282 wrote:
> 
>> On 8/4/26 03:10, rbowman wrote:
>>> On Mon, 3 Aug 2026 20:50:24 -0400, c186282 wrote:
>>>
>>>>      Anyway, hardware PLCs are pretty stupid - you don't actually hack
>>>>      them directly. They're basically a replacement for a box of relays
>>>>      or equivs. Software PLCs - a uC or even better - are more
>>>>      "computers",
>>>>      oft net-connected these days. An Ard Uno would make a fair
>>>>      software PLC. A low-end PI even better.
>>>
>>> https://www.realpars.com/blog/plc-hardware
>>>
>>> What's a hardware PLC?
>>
>>     There ARE 'chips' ... or, cruder, boards with a lot of transistors.
> 
> Semantics. A transition device was Square D's NorPak system. There were a
> number of different cards that that mounted in a frame similar to  a
> backplane. NOR gates are the simplest so those were the basic building
> blocks. Working with NOR, NAND, and NOT gates leads to brain bleed.
> 
> https://www.ebay.com/itm/Norpak-Square-D-8852-L-19-Counter-4-Input-NOR-20-
> Pack-Series-A-FREE-SHIPPING-/282588704448
> 
> 'Programming' was done by stripping wire, crimping on a tapered pin, and
> seating it with a too like an automatic center punch. Solid state relay
> logic...

Today its probably easier to have e.g. an RP2030 in there.

Car ECMs are essentially state machines. For each combination of 
sensors, there is an optimal set of output switches. And because memory 
is easer to manufacture than PLCs they hold the whole engine state 
machine map in NVRAM



-- 
Of what good are dead warriors? … Warriors are those who desire battle 
more than peace. Those who seek battle despite peace. Those who thump 
their spears on the ground and talk of honor. Those who leap high the 
battle dance and dream of glory … The good of dead warriors, Mother, is 
that they are dead.
Sheri S Tepper: The Awakeners.