Eaton EASY222-DN, Руководство пользователя

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DeviceNet functions
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09/10 MN05013007Z-EN
Four message groups of differing sizes are available to suit
the utilization model.
In DeviceNet language terms the CAN identifier is referred to
as the Connection ID. This is comprised of the identifier for
the message group (Message ID) and the MAC ID of the
device:
• The source and target addresses are possible as the MAC
ID; the definition is dependant on the message group and
message ID.
• The significance of the message is defined in the system
with the message ID.
The world of the DeviceNet provides four message groups.
The EASY222-DN uses message group 2. This group uses
512 CAN identifiers (400
hex
– 5FF
hex
). Most messages Ids of
this group are optionally defined for using the Predefined
Master/Slave Connection Sets. A message ID is used for
network management. The priority is defined here primarily
by the device address and only then by the message ID. A
closer look at the bit position shows that a CAN controller
with an 8-bit mask is able to selectively filter out its group 2
messages.