Re: Ada for Automation

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Thu, 6 Nov 2014 03:14:43 -0800 (PST), slos wrote:

First of all, congratulate and thank for the efforts.

Don't mind a little bit critique which follows.

> "Ada for Automation" (A4A in short) is a framework, for designing
> industrial automation applications using the Ada language. It uses the
> libmodbus library to allow building a Modbus TCP client or server, or a
> Modbus RTU master.

> It can also use Hilscher communication boards allowing
> to communicate on field buses like AS-Interface, CANopen, CC-Link,
> DeviceNet, PROFIBUS, EtherCAT, Ethernet/IP, Modbus TCP, PROFINET, Sercos
> III, POWERLINK, or VARAN.

In other words it does not implement the corresponding stacks? E.g.
EtherCAT master.

Regarding communication boards, they are not very useful. I can guarantee
you that the same EtherCAT would be impossible to talk to using such a
board. The protocol requires a very complicated initialization to talk even
with relatively simple slaves. You might be able to connect a simple
analogue I/O terminal, but nothing beyond that. Even TwinCAT, which is
vendor's tool does not support everything. Our EtherCAT master does, almost
(:-)).

So, my advice would be to implement these stacks natively. Yes, it is a
huge amount of work and you will need community support.

Even CANOpen master is many thousands times more complex than ModBus +
support of various CAN controllers under various OSes.

EtherCAT master is thousands times more complex than CANOpen + raw Ethernet
drivers needed for Windows.

This is not one-man job.

> Thanks to GtkAda it can be built with a GUI.
> It can be built without of course.

Do you mix data acquisition and distribution middleware with the GUI? That
is not a good idea, generally. It is better to keep them separate. Which is
a serious architectural problem how to communicate between the middleware
dealing with the hardware, providing publisher-subscriber services and
various clients. GUI is only one of them. Inter-process communication, DLLs
are all system-dependent. No solution is scalable and portable, meets
real-time requirements. It is a very difficult problem to resolve.
 
> It works rather nicely but it would be fantastic if some experienced
> person would review the code and give me some feedback on the design, the
> bindings, the code quality... I'm a lonely Ada programmer, and I miss
> feedback.
> 
> Of course, I am interested in any collaboration around this matter.
> So, do not hesitate to get in touch when you have some real case.

We do the same stuff, but it is a commercial product. So I cannot do that
on ethical and contractual grounds, sorry.
 
-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de