Lenze I/O system 1000 System Manual - Manual (Page 391)

PROFIBUS communication
Communication
Acyclic data transfer
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391 EDSIO1000 EN 7.0
9.3.3 Acyclic data transfer
The PROFIBUS−DP−V1 service can be used as an optional extension to enable an acyclic
parameter data transfer. PROFIBUS−DP−V0 and PROFIBUS−DP−V1 may be operated
simultaneously in one network.
The integration of the acyclic service in a fixed bus cycle depends on the correct
configuration of DPM 1:
ƒ If configured, a time slot is reserved.
ƒ If not configured, the acyclic service is added when a DP−V1 slave is accessed
acyclically with a DPM 2.
ƒ The acyclic service always has lower priority.
Parameter data transfer between DPM 1 and slaves
Token
Master 1
(DPM 1)
Master 2
(DPM 2)
Slave 1 Slave 2 Slave 3
epm−t229
Fig. 9−4 Acyclic data transfer
Cyclic process data transfer between DPM 1 and slave 1 ... 3
Acyclic parameter data transfer between DPM 1 and slave 3
1. DPM 1 has the send authorisation (token) and communicates in a fixed sequence
with slave 1, then with slave 2 etc. up to the last slave of the current list via the MS0
channel by means of request and response.
2. DPM 1 transfers the token to DPM 2.
3. During the remaining cycle time (time slot), DPM 2 establishes an acyclical
connection to one of the slaves in order to transmit parameter data via the MS2
channel.
4. At the end of the running cycle time, DPM 2 returns the token to DPM 1.
– Depending on the remaining cycle time, several time slots may be required for the
acyclical data record transfer.
5. Once all of the data records have been transferred, DPM 2 establishes the
connection within one time slot.
)
Note!
DPM 1 can perform the acyclical parameter data exchange via the MS1
channel.