Delta DVP-ES2/EX2/SS2/SA2/SX2/SE manual Emcy, Nmt, Command specifier Function Hex

7 CANopen Function and Operation

	Initialization	Pre-operational	Operational	Stopped
EMCY		X	X
Boot-up	X
NMT		X	X	X
The format of the control message for the node state:

COB-ID		Byte 0		Byte 1
0	Command specifier (CS)			Slave address
				(0: Broadcast)
The command specifiers are listed below.
Command specifier			Function
(hex)
01			Start the remote node
02			Stop the remote node
80		Enter the pre-operational state
81		Reset the application layer
82			Reset the communication

—Error control services

The error control service is used to detect the disconnection of the node in the network. The error control services can be classified into two types, i.e. Heartbeat and Node Guarding. The PLC only supports Heartbeat. For example, the master can detect the disconnection of the slave only after the slave enables the Heartbeat service.

The Heartbeat principle is illustrated as follows. The Hearbeat producer transmits the Heartbeat message according to the Heartbeat producing time which is set. One or many Heartbeat consumers detect the message transmitted by the Heartbeat producer. If the consumer does not receive the message transmitted by the producer within the timeout period, the CANopen communication is abnormal.

Heartbeat producer	Heartbeat consumer
Request	Receiving
Heartbeat	Receiving
	Receiving
producing
time	Heartbeat
	timeout
	period
Reuqest

Heartbeat timeout period

Heartbeat evnet

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