Axel CANDPSX - The Node Guarding Service

CANDPSX user manual rev 2 Page 19 of 42
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4.2.5 The Node guarding service
The CANDPSX module can perform node guarding, complying with what stated in the CiA DS301
standard.
To activate this service, set the parameter 20B0h:
Property
Value
Parameter
20B0h
Logic View manu
All parameters/System/CANopen Master/Node guarding services
Data type
8 bit unsigned int
Measurement unit
--
Value
0 = control disabled
1 = control enabled
Default value
0
Access
Read/Write
If the service is enabled, after scanning the network the CANopen master sends the nodes the
Guard time and Life time factor values as programmed in the parameters 20B2h and 20B1h
respectively, in order to activate Node guarding of the nodes themselves. Once the nodes have
entered the running state, the CANopen master begins to poll them with the Node guarding
protocol. Guard time is the polling period of each node. In order to disable Node guarding, just set
the Guard time or the Life time factor to zero. The master executes anyway Node guarding with a
polling period of 100 ms.
Like what mentioned in § 16 concerning validation of a configuration, the CANopen master
publishes the Node guarding status of nodes in the parameter 20B3h, which can also be mapped
in the Profibus dual port (see § 28).
To specify the Guard time, set the parameter 20B2h:
Property
Value
Parameter
20B2h
Logic View menu
All parameters/System/CANopen Master/Node guarding services
Data type
16 bit unsigned int
Measurement unit
ms
Default value
0
Access
Read/Write
To specify the Life time factor, set the parameter 20B1h:
Property
Value
Parameter
20B1h
Logic View menu
All parameters/System/CANopen Master/Node guarding services
Data type
8 bit unsigned int
Measurement unit
--
Default value
0
Access
Read/Write