FDT Tools
FDT-Specification Basics
ifak system GmbH
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Figure 1: FDT Object Model
At this point two new terms are introduced, which are not con-
tained in the FDT specification but seem to be helpful for an eas-
ier understanding of the specification.
A DTM for a device class without any direct access to the com-
munication (the use of the FDT communication functions not-
withstanding) is named DeviceDTM. In order to configure a
field device (sensor, actuator) within a FDT compliant engineer-
ing system one Device DTM must exist for every device. The
DeviceDTM will be provided by the device manufacturer.
A DTM for a device class with direct access to a communication
device (e.g. a Profibus interface) is named CommDTM. The
CommDTM encapsulates all communication specific aspects. It
is responsible for the management and configuration of the com-
munication interface. Other applications (DTMs) call its Com-
mChannels for field communication access. The CommChannel
can be provided by an additional CommDTM or by the Frame
Application.
DeviceDTM and CommDTM differ mainly in the type of chan-
nels a DTM supports. A Channel represents either a communica-
tion (CommChannel) or data channel (DataChannel). A
