Siemens SINUMERIK 840DE SL - Page 1245

Detailed Description
2.7 Structure and functions of the basic program
PLC Basic Program Solution Line (P3 sl)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
2-51
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Fig. 2-15 DB 20
Note
If the number of PLC machine data used is increased later, then DB20 must be deleted
beforehand. To prevent such extensions in use having any effect on the existing user
program, the data in DB20 should be accessed in symbolic form wherever possible, e.g., by
means of a structure definition in the UDT.
Interrupts
400120 Delete DB 20 in PLC and restart
Explanation DB length is not the same as the required DB length
Reaction Interrupt display and PLC STOP
Remedy Delete DB 20 followed by Reset
Continuation After cold restart