5
5.8
Motion Control with PROFIBUS–DP (from SW 3.1)
5-302
Siemens AG 2005 All Rights Reserved
SIMODRIVE 611 universal Description of Functions (FBU) – 04.05 Edition
The following criteria must be taken into account when setting the times:
DP cycle (T
DP
)
– Time T
DP
must be set the same for all bus nodes.
– The following must be valid: T
DP
> T
DX
and T
DP
T
O
Time T
DP
is therefore long enough to permit communications
with all of the bus nodes.
– Specific reserves must be available
This means that additional masters can be connected and non–
cyclic communications can be realized.
T
I
and T
O
– n–set mode: Setting the times in T
I
and T
O
as short as possible
reduces the dead time in the position control loop.
– The following must be valid: T
O
> T
DX
+ T
Omin
The following is valid for interpolating axes:
– T
I
of the interpolating axes should be the same
– T
O
of the interpolating axes should be the same
5.8.4
Bus run–up, synchronization and net data save
When running–up, the DP master checks the DP slave by requesting
diagnostic information.
The following faults/errors are identified:
Parameterizing and configuring errors
The DP slave has been assigned to another master
Static user diagnostics
Operational readiness of the DP slave
If a fault has not been detected, then the DP master, with this DP
slave, goes into cyclic net data operation, i.e. input and output data are
exchanged.
With the transition into cyclic net data transfer, the DP slave is synchro-
nized to the master sign–of–life.
The DP slave runs in synchronism with the master, if
The status signal ZSW1.9 (control requested/no control possible) =
”1”
and
The slave sign–of–life (ZSW2.12 to ZSW2.15, value = 1 to 15) is
counted
Setting criteria
Bus run–up and
synchronization
5 Communications via PROFIBUS DP
08.99
08.01
