Linking To The User Program - Siemens SIMATIC S5 Manual

Application Examples
6.6.8

Linking to the User Program

The application illustrated in Chapter 6.6 corresponds to the program example
6.6.9. The user program has the following structure:
OB 21 OB 22
OB 1
:
:
:
: JC FB 50
:
:
:
:
:
:
:
: JC FB 51
:
:
:
:
:
: BE
Figure 6-7. Structure of the User Program "Loading
The IP 267 is configured with a new data set with FB 50. FB 53 then executes a
reference point approach to point C. Point C is taken as the reference point in the
example program.
Since the reference point is lost whenever the positioning program is interrupted,
FB 50 must be called on all cold restarts or warm restarts of the CPU. OB 21 and
OB 22 are used for this purpose: they prepare the conditional jump to FB 50.
The positioning program is then started by calling FB 51.
6-38
FB 50
:
:
:
JU FB 53
:
:
:
BE
FB 51
:
:
:
:
:
:
BE
and Unloading a Waggon"
IP 267
FB 53
:
:
:
:
: BE
EWA 4NEB 812 6061-02a