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2 Basic principles of the counter module
Counter Module SIMATIC FM 350-2
V1.0, Item ID: 83146298
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2.4
Counting rages of the module channels
Channels 0-3
Channels 0-3 are read via the process image input of the called OB.
The counting range of these channels can be changed in the HW configuration
of the counter module.
Note
The instructions for the configuration can be found in chapter 3.6.9
In the default setting, all four channels are assigned to a WORD data area.
It is possible to combine two channels that have a WORD data format in one
DWORD channel. This configuration option is available for channels 0 and 2.
For example, if you assign channel 0 to a DWORD data area, you can no longer
use channel 1. The reason for this is that channel 0 blocks the process image data
area that was reserved for channel 1. The same thing applies to channel 2 with
respect to channel 3.
Table 2–3: Possible configurations of channels 0-3
WORD only
Mixed configurations
DWORD only
Channel 0
Channel 0
Channel 0
Channel 0
Channel 1
Channel 1
Channel 2
Channel 2
Channel 2
Channel 2
Channel 3
Channel 3
Note
Counting range in WORD (16-bit) and DWORD (32-bit)
WORD = -32,768 to 32,767
DWORD = -2,147,483,648 to 2,147,483,647
Channels 4-7
Channels 4-7 are read via the peripheral input words and counted in the DWORD
area.
Here, configurations of the counter range similar to those for channels 0-3 are not
possible.
Note
DWORD (32-bit) counting range
DWORD = -2,147,483,648 to 2,147,483,647