Experimental Physics and
Industrial Control System

John Dobbins <[email protected]> · Mon, 10 Oct 2005 08:36:30 -0400

Paul,
I looked at the available modbus code a few months ago and found it
supported only a small subset of modbus codes. It seems it was developed
for talking to a particular PLC, via register reads and writes, rather
than a more general modbus device. If your goal is similar you may be
happy with the CLS/BNLS code. If your goal is to be able to support a
variety of modbus devices you'll need to do some additional
device/driver development.
Sheng,
I am also interested in learning about the modbus device support at SNS.
John Dobbins
Research Support Specialist
Laboratory for Elementary Particle Physics
Cornell University

Paul Sichta wrote:

Sheng,

I visited SNS a few weeks ago and Ernest showed me the Beckhoff hardware
which he said you wrote a modbus driver/device support for. Was that
working well? I am thinking of trying out the Beckhoff stuff.
I will be supporting some modbus tcp/ip devices in the near future and
have the CLS and some upgraded (APS?) source but haven't looked at it
yet. What limitation did that have for you, so that you needed to write
a new version?
Regards,

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System