Industrial Communication Systems

46-6 Industrial Communication Systems

standard tasks may also be assigned to different controllers and networks as shown in Figure 46.8.

Any so-called

acyclic

communications

between

devices

and

controllers

or

supervisors

such

as

program-

ming

devices are intended for conguration, parameterization, diagnosis, and maintenance purposes.

46.2.4 Cyclic Communication PDU

e PDU (protocol data unit) structure of the Probus I/O data exchange message is exactly the same

whether

or

not

there

is

any

safety

data

in

the

message.

is

structure

has

separate

data

areas

assigned

to

each

module

in

a

modular

slave

device,

facilitating

the

intermixing

of

safet ...