Siemens MICROMASTER 420 Operating Instructions Manual page 35

Issue 01/05
Heartbeat:
The MICROMASTER 420/430/440 also supports the Heartbeat protocol as
Heartbeat Producer. With the Heartbeat protocol, a Heartbeat Producer cyclically
sends its NMT state to the CAN bus. The message does not contain a Toggle bit.
The Heartbeat Producer object is used to define the time between two heartbeat
messages. One or several Heartbeat Consumers expect the telegram of the
Heartbeat Producer after the Heartbeat Consumer Time. If this message is not
received, then the consumer initiates a Heartbeat event. The error message sent
(EMCY) is the same as for Node Guarding/ Life Guarding.
NOTE
Only one communication monitoring service may be activated. This is either Node
Guarding/Life Guarding or Heartbeat.
Heartbeat Producer
Producer time
Fig. 3-4
SYNC Loss Detection:
The third communication monitoring is the SYNC loss detection.
The SYNC Producer sends cyclic SYNC telegram (this does not contain any data)
with the SYNC producer time (object 1006H Communication cycle period) and the
COB-ID 80H. The MICROMASTER 420/430/440, as SYNC consumer, monitors
whether the SYNC telegram is sent in the SYNC Consumer time (object 1006H
Communication cycle period multiplied by 1.5). If the SYNC producer doesn't send
the SYNC telegram within the defined time (SYNC loss event), then
MICROMASTER responds the same as for a Heartbeat- or a Life Guarding Event.
CANopen Option Module Operating Instructions
6SE6400-5BC00-0BP0
COB-ID = 700H + Node-ID
Request
Heartbeat
Request
Heartbeat protocol
Data transfer using CANopen
7 6 ... 0
r s
7 6 ... 0
r s
Heartbeat Consumer
Indication
Heartbeat
Consumer time
Indication
Heartbeat
Consumer time
Heartbeat Event
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