Re: Ada in command / control systems

[russ lyttle <lyttlec@removegmail.com>]

On 2/25/19 3:24 AM, Dmitry A. Kazakov wrote:
> On 2019-02-25 07:51, Jesper Quorning wrote:
>>
>> Why is Ada not used on industrial programmable logic controllers (PLC) 
>> platforms?
> 
> Because the PLC marked is dominated by vendors pushing their vendor-lock 
> solutions, e.g. Siemens.
> 
> Another reason is the customers lacking elementary programming and 
> software design skills. They are usually technicians and electrical or 
> mechanical engineers.
> 
>> In the IEC 61131-3 standard, the language 'structured text' is 
>> defined. The language looks like the poor man's Ada.
>>
>> I have not worked with structured text, but with SCL (Structured 
>> Contol Language) for Siemens S7-300 / 400/1200/1500. It looks like 
>> there are elements of Ada in it.
> 
> Is it a joke?
> 
>> Should industrial programs not be Ada's wheelhouse?
> 
> Possibly, if Ada community would pay attention to the emerging market of 
> single board computers used at home.
> 
> In about 5-10 years so-called industrial solutions will be swept away by 
> cheap hardware and hobby software coming from the home automation toy 
> projects. These will be far worse than awful SPS, who could think that 
> worse were possible? But the force of mass market is overwhelming. SPS 
> et al will suffer the same fate as workstations did.
> 
Languages like VHDL and SCL do borrow a lot from Ada. I've noticed that 
it is much more difficult for C/C++ programmers to learn VHDL or SCL 
than Ada programmers. But, as you say, the Ada community seems to be 
ignoring the areas where these languages are applied.

There is some support for STM (thanks Simon Wright) but has  anyone 
tried to write an Ada program for an AT Tiny? Have you noticed how many 
*.py files are in the Ada_Drivers_Library? Or how horrible gnat is on 
memory management?

Another point, having an OS written in Ada would make qualification of 
software much much easier. No need to qualify C/C++ or Python. In my 
case an Ada equivalent of Minix-1 or uCOS (first version published in 
Embedded Systems) would be very handy.