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User manual SCAIME:
NU-Soft-eNod4F-E-0716_235704-C.doc
Two parameters of the object dictionary are necessary to set and define node guarding protocol: the
‘guard time’
and
the
‘life time factor’
:
Guard time
: this parameter expressed in milliseconds indicates the period with which the node is
being polled by the NMT master. This value can be different from one node to another.
Life time factor
: when node guarding protocol is active,
node life time
is given by multiplication of the
guard time and the life time factor.
Node guarding activation is effective when guard time has been set (and if Heartbeat protocol is not used) and after
reception of the first remote transmit request. If life time factor is also configured and if no remote transmit request is
handled within the node life time,
eNod4
sends an emergency telegram then switches to pre-operational state
. The
life guarding error is acknowledged when the state is changed by a NMT command and after reception of a new
remote transmit request.
Switching to the stopped NMT state because of a node guarding error may cause
eNod4
to be set into a configurable
safety mode where parts of its functioning are inhibited
5.7
Access to the object dictionary
The most important element of a CANopen® compatible device is its
object dictionary (OD)
. Each node object that can
be accessed via the bus is part of a table called object dictionary. The dictionary entries can be addressed by a couple
of an index (2 bytes) and a sub-index (1 byte) with the following organization:
Index (hex.)
Object type
0000
reserved
0001
001F
static data types
0020
003F
complex data types
0040
005F
manufacturer specific complex data bytes
0060
007F
device profile specific static data types
0080
009F
device profile specific complex data types
00A0
0FFF
reserved
1000
1FFF
communication profile area
2000
5FFF
manufacturer specific profile area
5FFF
9FFF
standardized device profile area
A000
FFFF
reserved
Only the greyed elements of the table are accessible through
eNod4
OD.