Experimental Physics and
Industrial Control System

Zenon Szalata <[email protected]> · Fri, 17 May 2013 14:39:15 -0700

Hi Mark,

Some of what I wrote in my previous email is no longer relevant. I have

since played with controlling the polling timeout to reduce the

interference between the reads done in the polling thread and the

write-reads that I am attempting from my rather complicated set of EPICS

records. I have reached a conclusion, hopefully correct, that what I

really need is a Modbus device driver that would give me a full control

when and in which order register read and write operations are performed.

Is this possible with the existing Modbus support module?

I am thinking that it would be very nice to have a C++ base class like

asynPortDriver, or perhaps a subclass of asynPortDriver, which would

implement all the details of Modbus protocol and basic IO.

Have you thought of writing something like that?
Do you think such a class would be useful?

Beckhoff are the only modbus devices that I have written software for

and the stepper motor controllers are the only devices for which I find

your Modbus support module too limited. For that reason I am a bit

hesitant to start a new project, that is to write the C++ class. Could

you offer your insight on this?

Thanks in advance,
Zen

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System