ElmoMC CANopen DS 301 Implementation Guide - Manual (Page 40)

Chapter 7: Network Management (NMT)
Only the minimum, required, set of network management (NMT) services is supported
by SimplIQ. NMT commands are used to control the communication state of the servo
drive and to broadcast manufacturer messages to all other connected servo drives.
The following network communication states are supported:
State Description
Unpowered/Initialization Servo drive is not ready, or it is booting. Drive will not
respond to communication and will not transmit anything.
Pre-operational Servo drive boot sequence is complete, but no command has
been received to enter operational mode. The servo drive will
respond to SDO and NMT messages, but not to PDOs.
Operational Servo drive is fully operational, responding to PDO, SDO
and NMT messages.
Stopped Servo drive can respond only to NMT objects (including
heartbeats).
Table 7-1: Network Management (NMT)
Figure 1-1: State diagram of a device
When the servo drive is powered on, it enters the initialization state. After completing the
boot sequence, it automatically enters the pre-operational state. The transition between
pre-operational, operational and prepared states is carried out according to Network
Management (NMT) messages. The COB-ID of an NMT command is always 0.
An NMT message is always two bytes long: the first byte is the command specifier and
the second byte is the ID of the units that are to respond to the message. If the ID is 0, the
NMT message will be executed by the entire set of connected servo drives.
CANopen DS 301 Implementation Guide Network Management (NMT)
MAN-CAN301IG (Ver. 2.1)
7-1