The direct display of individual memory locations is done through the use of special character sequences. These sequences are a concatenation of the percent sign "%", a range prefix, a prefix for the size and one or more natural numbers separated by blank spaces.
|
I |
Input |
|
Q |
Output |
|
M |
Memory location |
|
X |
Single bit |
|
None |
Single bit |
|
B |
Byte (8 bits) |
|
W |
Word (16 bits) |
|
D |
Double word (32 bits) |
Examples:
|
%QX7.5 and %Q7.5 |
Output bit 7.5 |
|
%IW215 |
Input word 215 |
|
%QB7 |
Output byte 7 |
|
%MD48 |
Double word in memory position 48 in the memory location. |
|
%IW2.5.7.1 |
Depending on the PLC configuration |
|
ivar AT %IW0 : WORD; |
Example of a variable declaration including an address assignment |
The current PLC configuration for the program determines whether or not an address is valid.
Boolean values will be allocated bytewise, if no explicit single-bit address is specified.
Example: A change in the value of varbool1 AT %QW0 affects the range from QX0.0 to QX0.7.
Online Change might change the contents on addresses.
Please regard this when using pointer on addresses⮫ “Pointer”.