Siemens SIMATIC S7 System Manual page 375

Example: Table
The following program creates a table with 20 entries. The first memory location of the table
contains the length of the table (in this case 20 entries). The second memory location shows
the current number of table entries. The other locations contain the entries. A table can have
up to 100 entries. It does not include the parameters defining the maximum length of the
table or the actual number of entries (here VW0 and VW2). The actual number of entries in
the table (here VW2) is automatically incremented or decremented by the CPU with every
command.
Before you work with a table, assign the maximum number of table entries. Otherwise, you
cannot make entries in the table. Also, be sure that all read and write commands are
activated with edge instructions.
S7-200 SMART
System Manual, V2.3, 07/2017, A5E03822230-AF
Program instructions
7.16 Table
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