SV-iS7 CANopen Manual
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The ’t’ of the top bit is the Toggle Bit which toggles at every response of the Slave.
The Master sends the RTR Frame at every preset Node guard time. If the Master fails to send RTR Frame until
the expiration of the Node life time, or the Slave fails to response to the Mater until the expiration of the Node life
time, a Guard Error is generated. Then, the Guard Error Event set up in each Master and Slave is executed. In the
case of iS7, the CANopen NMT State is changed to Pre-operational.
4.3.2 Protocol
heartbeat
If the Error Control Protocol is set to Heartbeat, the MNT State information of itself is sent at the time intervals set
up in the Heartbeat Producer. If the Heartbeat Producer fails to send the Heartbeat within the preset time, the
Heartbeat consumer generates a Heartbeat event.
The value of S represents the MNT state of the Slave;
-. 4: Stopped
-. 5: Operational
-. 127:Pre-operational
The upper ‘r’ is the reservation bit which is always zero.
The IS7 CANopen informs the Consumer of the current MNT State at the time intervals set up with the
Producer. Therefore, in general, the Master is the Consumer.