Siemens SIMATIC S5 Manual page 125

Function block for assigning parameters to the IP 267
Application of function block FB 17
This function block supports operator communication and visualization using the
IP 267 stepper motor controller in conjunction with the CPU 102 (from 6ES5 102 -
8MA02 onwards) or CPU 103.
To facilitate configuring and positioning, the various parameters can be trans-
ferred to different data words of the user data block. The function block has
access to this data area and converts the parameters to the required 4-byte
format.
Additionally, the traversing path (linear axis) or the angle of rotation (rotary axis)
can be entered directly and the residual distance or angle read. This relieves the
user of having to convert the distance (angle) to go into the corresponding
number of pulses, and vice versa.
General note on communications
As the PII and PIQ are updated simultaneously, the feedback messages are de-
layed by one OB 1 cycle. To avoid undesirable reactions of the user program to
the "old" data, the positioning functions and the output of new positioning or
configuration message frames must be deactivated in the user program for every
second OB 1 cycle.
7.2 Structure of function block 17
General
Communication between the CPU and the IP 267 is limited to three different
types of message frame:
- Configuration message frames
Positioning message frames
-
Feedback message frames.
-
The FB 17 includes one separate segment for each type of message frame and an
additional one for calling the user program.
Segment 1 - Read feedback message frame
Segment 2 - Calling user program
Segment 3 - Transmit configuration message frame
Segment 4 - Transmit positioning message frame
7-2
IP 267
EWA 4NEB 812 6061-02a