BRONKHORST HIGH-TECH B.V.
9.17.024
Page 14
3 FLOW-BUS
system
operation with computer
There are several options to do this.
First see that the chosen hardware is able to communicate with the FLOW-BUS system and that this can be
done with a sufficient velocity of parameter transfer for your application.
3.1 Communication with FLOW-BUS DDE server
Together with a client-application, either self-made or with a SCADA-program from 3rd-parties.
Examples: Genesis, Fix-MMI, Lotus Measure, Paragon, Wizcon, LabView, Intouch.
This option is far most convenient, less costful and most user friendly.
The FLOW-BUS DDE server also offers a lot of test facilities and user adjustable settings for efficient
communication with devices connected to the FLOW-BUS.
Programming examples are available for making applications in: Visual Basic, LabView and Excel.
Advantage:
Very powerful, fast communication, no special knowledge needed from bus-protocol and bus-system,
supported by BHT
Disadvantage:
not really, depends on demands of user:
can be used under Windows 95 and higher and Windows NT4.0 and Windows2000 only
large systems with need of very high update rates of data
(within < 1 sec.) is not possible
3.2 Communication
with
FLOW-BUS directly through DLL
Part of this FLOW-BUS software is a 32-bit DLL (for Windows95 and higher, Windows NT 4.0 and
Windows2000).
You may call the functions in this library directly to communicate with devices on the FLOW-BUS.
Further documentation may be ordered at your local sales representative.
Programming examples are available for making applications in Visual Basic and LabView.
Advantage:
powerful routines available for fast communication, less overhead, low processor load
Disadvantage:
knowledge needed from FLOW-BUS system about parameters, processes, nodes etc., complex
software structure, not suited for quickly building an application
3.3 Communication
with
interface directly through RS232
Mostly used by PLC-equipment or special PC-applications (e.g. Hyperterminal).
You have to write your own communication routines for operating the FLOW-BUS system by host computer.
The protocol for the communication between the modules is described in a PDF-file doc.nr. 9.17.027.
For an RS232-interface module messages will be send by means of ASCII-strings (or binary).
Advantage:
simple, straight forward, less overhead
Disadvantage:
knowledge needed from FLOW-BUS system about parameters, processes, nodes etc.
