Examples of Calculations
21
S7-400 Instruction List
A5E00267845-01
Examples of Calculations
You will find a few examples here for calculating the execution times for the various methods of indirect addressing.
Calculating the Execution Times for Area-Internal Memory-Indirect Addressing
Example:
A I [DBD 12] with CPU 414
Step 1:
Load the contents of DBD 12 (time required is listed in the table on page 20)
Address is in ...
Execution Time in
s
Bit memory area M
Word
Double word
0.2
0.3
Data block DB/DX
Word
Double word
0.3
0.2
Step 2:
AND the input addressed in this way (you will find the execution time in the tables in the chapter entitled “List of Instruc-
tions” on page 25)
Typical Execution Time in
s
Direct Addressing
Indirect Addressing
0.06/0.075
:
0.06+
:
Time for A I
Total execution time:
0.18
s
+
0.06
s
0.24
s