Chapter 2 Decentral block periphery CAN-Bus CANopen
Manual VIPA System 100V
2-42
HB100E - SM-CAN - Rev. 15/02
The bus coupler supports the Node Guarding defined by CANopen, to
guarantee the control of the bus participants.
The guarding operation of the module starts with the first guarding request
telegram (RTR) received by the master. The assigned COB identifier is
fixed in the object directory in the variable 0x100E at 0x700 + module-ID. If
during the guarding operation the master doesn't receive further guarding
request telegrams within the "guard time" (object 0x100C), the module
assumes that the master is not working proper anymore. After the time,
fixed by the multiplication of "guard time" (0x100C) and "Life-Time-Factor"
(0x100D), the module automatically switches to the state "pre-operational".
If either the "guard time" (object 0x100C) or the and "Life-Time-Factor"
(0x100D) is set to 0 by the master by means of a SDO download, the
expiration of the guarding time is not proofed and the module stays in the
current state.
Besides of the node guarding the VIPA CAN coupler also supports the
heartbeat mode.
If you are typing a value into the index 0x1017 (Heartbeat Producer Time),
the device state of the bus coupler (operational, pre-operational, ...) is
transmitted via COB identifiers(0x700+module-ID) as soon as the heartbeat
timer expires.
The heartbeat mode starts automatically as soon as a value different from 0
is typed in.
Node Guarding
Heartbeat