18
Curtis 1356/1356P CAN Expansion Module Manual,
Rev. A
NMT MESSAGES
NMT (Network Management Transmission) messages are the highest priority
message available. The NMT message puts the 1356 /1356P into a specific
Device State, as shown below. These messages have 2 bytes of data sent by the
master; the slave does not respond with any data to an NMT.
The Device State value can be queried over the CAN bus using an SDO.
The Device State value is also transmitted with each heartbeat message.
Value
Device State
0
Initialization (or “boot-up”)
4 Stopped
Xx
5 Operational
Xx
127 Pre-Operational
Xx
The NMT message identifier consists of the standard message type, NMT,
in the top four bits. The bottom seven bits must be set to zero.
The first data byte of the NMT command is the command specifier. The
1356 /1356P will respond to the following commands.
Value
Command Specifier
0x01
Enter the Operational state
0x02
Enter the Stopped state
Xx
0x80
Enter the Pre-Operational state
x
0x81
Reset the 1356 /1356P (warm boot)
0x82
Reset the CAN bus
Xx
The second byte of the NMT command defines whether this NMT is for
all slaves on the bus (data byte = 0x00) or for a specific node (data byte = Node
ID of the 1356 /1356P).
3 — CANopen COMMUNICATIONS
Summary of Contents for 1356
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