Siemens SIMATIC S7-300 Manual page 259

Rotary axis The end position of MD
When traveling into the working range (e.g. end position was previously
switched off), the shortest path is always chosen.
If both default values are parameterized the software limit switches are inac-
tive.
9.10 Process interrupts
Overview Process interrupts are interrupts that quickly signal states in the current pro-
cess to the user program.
The appropriate setting in the machine data (MD5) specifies which signals
are to be quickly communicated to the user program.
Process-interrupt The process interrupt is generated by way of machine data item MD5:
generation
Hint to the user You must program the interrupt processing routine in OB40.
The prerequisite is that process-interrupt signaling must have been activated
as part of the environment definition (see Chapter 5).
FM 354 Servo Drive Positioning Module
may be greater than MD
start
MD Designation
5 Process-interrupt generation
(data type - bit field)
Description of Functions
stop.
Significance
0 = Position reached
1 = Length measurement completed
3 = Change block on-the-fly
4 = Inprocess Measurement
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