Siemens SINUMERIK 840D sl Function Manual page 1050

Detailed description
2.7 Structure and functions of the basic program
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
Explanation
Response
To correct or
avoid errors
Continuation
Example
The project in the example requires 4 integer values, 2 hexadecimal fields with bit
information and 1 real value.
Machine data:
MD14510 USER_DATA_INT[0]
MD14510 USER_DATA_INT[1]
MD14510 USER_DATA_INT[2]
MD14510 USER_DATA_INT[3]
...
MD14512 USER_DATA_HEX[0]
MD14512 USER_DATA_HEX[1]
...
MD14514 USER_DATA_FLOAT[0]
GP Parameter (OB 100):
CALL FB 1, DB 7 (
66
Delete DB 20 in PLC and restart
DB length is not the same as the required DB length
Interrupt display and PLC Stop
Delete DB 20 followed by RESET
After cold restart
MCPNum :=
MCP1In :=
MCP1Out :=
MCP1StatSend :=
MCP1StatRec :=
MCP1BusAdr :=
MCP1Timeout :=
MCP1Cycl :=
NCCyclTimeout := S5T#200MS,
123
456
789
1011
12
AC
123.456
1,
P#E0.0,
P#A0.0,
P#A8.0,
P#A12.0,
6,
S5T#700MS,
S5T#200MS,
Basic logic functions: PLC Basic program powerline (P3 pl)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0