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NETLink PRO ETH
Q: I use the rack/slot mode of the RFC1006 interface (rack/slot mode = ON)
and have specified address 2 for my existing CPU in the Web interface in
‘Fix destination address for R/S mode’.
Although NETLink PRO ETH online is active (active LED lights up), my
visualization system tells me that no link can be established.
A: Make sure you have assigned the correct values to rack and slot in the
parameterization. For example, to communicate with a CPU in a 300 rack,
you must enter '0' for rack and '2' for slot.
Many visualization system manufacturers have grouped together the two
fields. In that case, there may be a field with the name 'Remote TSAP'
containing a hex value such as '0102'. In this case, the hex value '02' stands
for rack 0 and slot 2.
Q: I would like to use addressed mode of the RFC1006 interface (rack/slot
mode = OFF) because that way I can access several CPUs on the same bus.
Unfortunately I am not sure how to parameterize the fields rack and slot in
the visualization used.
A: If addressed mode is used, a combination of rack and slot specifies the
destination address of the automation system.
If the CPU is to be addressed with bus address 2, the value 0 for the rack and
the value 2 for the slot must be entered.
Please note that the rack field consists of three bits and the slot field of five
bits – i.e. together they comprise one byte and eight bits. That means, for
example, the value 1 (00000001
Bin
; 01
Hex
) in the rack field must be entered
for bus address 49 (00110001
Bin
; 31
Hex
) and the value 17 (00010001
Bin
;
11
Hex
) in slot field.
For parameterization tools that offer a field with a name like
‘Remote TSAP’
for parameterization instead of separately parameterizable rack and slot
fields, the value of the bus address can be entered directly without being
taken apart and converted.
For example, for bus address 2, the hex value
‘0102’
can be entered and for
bus address 49 the hex value
‘0131’
.
An address conversion table is given in Section 10.3.1 to simplify this task.
Q: If I mix RFC1006 connections and connections via the STEP7 driver, the
link sometimes breaks off or error messages appear saying that it is not
possible to establish a link.
A: For communication with S7-300 modules it may be necessary to
parameterize the communication resources.
The user can influence the allocation of existing
‘Connection resources’
under object properties of the CPU in the hardware configuration.
Q: Once the configured PROFIBUS slaves have been added on my CPU,
communication between NETLink PRO ETH and STEP7 becomes markedly
slower.
A: The user can influence the allocation of
‘Scan Cycle Load from
Communication [%]’
under object properties of the CPU in the hardware
configuration. The default value is 20 %.
