PROFIBUS DP Communication
8.1 General information
Manual
Commissioning Manual, 05/2008, 6FC5397–4CP10–4BA0
233
Key to Fig. above:
●
T
MAPC
:
Master application cycle: NC-Position controller cycle
the following is always valid for SINUMERIK 840Di sl: T
MAPC
= T
DP
●
T
DP
:
DP cycle time: DP cycle time
●
T
DX
:
Data exchange time: Total transfer time for all DP slaves
●
T
M
:
Master time: Offset of the start time for NC position control
●
T
I
:
Input time: Time of the actual value acquisition. The actual values are transferred to the
DP-Master in the next DP cycle.
●
T
O
:
Output time: Time of the setpoint acceptance. The setpoints were generated by the DP-
Master-Application in the previous DP-Cycle.
●
GC:
Global control message frame (broadcast message frame) for cyclic synchronization of
the equidistance between the DP master and DP slaves
●
R:
Computation time for speed or position control
●
Dx:
Useful data exchange between the DP master and DP slaves
●
DPV1:
After cyclic communication, an acyclic service is sent, if the token holding time T
TH
has
not yet been exceeded. T
TH
is calculated by the engineering system.
●
G T R:
E: GAP
An attempt is made during this time to accept new active stations.T:
T: TOKEN
The token passing is either to itself or other masters.
R: RES
The reserve is used as an "Active break" for the station to send the token to itself until the
equidistant cycle expires.
●
①
The actual values for the current DP-Cycle/position control cycle are transferred from the
DP-Slave-Drives to the NC position controller.
●
②
The setpoints computed by the NC position controller are transferred to the DP-Slave-
Drives.
