Cyclic Communication Via Process Data Channel - Bosch Rexroth IndraDrive MPH-02 Functional Description

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Master Communication
Change Parameter

Cyclic Communication via Process Data Channel

ProfiDrive parameter request via DPV1
request request reference
header 1 to 255
axis
0
parameter attribute
address 16 = value
parameter number
sub-index
parameter format
value(s) 65 = bytes
66 = word
67 = double word
value(s)
...
DPV1 parameter response
response request ref. mirrored
header 1 to 255
axis mirrored
1
Communication Cycle Time
Cyclic communication via the process data channel takes place in the so-
called communication cycle (cf. P-0-4076, Field bus: cycle time (Tcyc)).
The communication cycle indicates the time intervals in which the cyclic
data are transmitted or processed.
Cycle times of the interface:
• basic design → 1 ms to 65 ms (in steps of 1 ms)
• advanced design → 500 µs to 65 ms (in steps of 500 µs)
Processing the Cyclic Data
The internal processing of the command values and actual values is
carried out synchronously with the control clock. As the communication
via PROFIBUS-DP is not carried out in a synchronous way, this type of
master communication is not suited for synchronous operating modes
such as "position control with cyclic command value input", but only for
positioning modes and velocity control.
In the drive only a limited number of cyclic data can be processed
Basic: 16 Byte; Advanced: 32 Byte).
(
Note: There is no limit value check for the cyclically transmitted
command values and they are not stored in volatile form.
Configuring the Process Data Channel
The cyclic data have to be configured in the parameter mode. The section
"Configuring the PROFIBUS-DP Slave" describes how the cyclic data are
configured.
MPH-02, MPB-02, MPD-02
request ID
2 = change parameter
number of parameters
1
number of elements
1
number of values
1 to 10
response ID
2 = positive acknowledge
130 = negative acknowledge
number of parameters
1
DOK-INDRV*-MP*-02VRS**-FK01-EN-P