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6.2
Enabling Transparent Ethernet
Transparent Ethernet is not enabled at delivery. Attribute #16 (instance #1) in the Anybus Ob-
ject (01h) has to be set to 0002h during setup. If this attribute is not changed, the Anybus Com-
pactCom 40 Modbus-TCP will start up with full IT functionality instead of transparent Ethernet
functionality. Transparent Ethernet cannot be enabled after setup is finished. Once Transparent
Ethernet is enabled, no IT functionality is enabled.
6.3
MAC Address Synchronization
The host application and the Anybus CompactCom must use the same MAC address when
communicating on Ethernet. The host application must make sure that this is the case. This can
be accomplished in ether of the two ways described below:
•
The pre-programmed MAC address in attribute #1 (instance #1) in the Network Ethernet
Object (0Ch) is read and used by the host application when communicating on Ethernet.
•
The Ethernet Host Object (F9h, instance #1, attribute #1) is implemented in the application,
set with a MAC address provided and used by the application. At initialization, the Anybus
CompactCom will read and then use the application provided MAC address from this
object.
6.4
IP Configuration Synchronization
The host application TCP/IP stack and the Anybus CompactCom 40 Modbus-TCP TCP/IP stack
must use the same IP configuration when communicating on Ethernet. The Anybus Compact-
Com 40 Modbus-TCP will write its currently used IP configuration to instance attribute #16 in
the Ethernet Host Object (F9h) whenever the configuration is assigned or changed. The host
application must use this configuration. DNS server and domain names can be read from the
Network Configuration Object (04h) after an IP configuration update.
6.5
Routing Restrictions
The internal router receives all frames from the network. The frames that are intended for the in-
dustrial Ethernet network internal software, are recognized and routed to the Anybus Compact-
Com. The remaining Ethernet frames will be routed to the host application. Some restrictions
apply to the use of e.g. UDP and TCP ports, sometimes also depending on industrial Ethernet
network. If the host application is intended only for use with Modbus-TCP, the restrictions for the
other networks can be ignored.
The host application is responsible for taking the following restrictions into
consideration. If they are not followed, the Ethernet communication will not work
correctly.
Anybus
®
CompactCom
™
40 Modbus-TCP
®
Transparent Ethernet Network Guide
SCM-1202-022 1.1