Automatic control function programming manual ladder language

Exchanges by Protocol
15.5.4 Setting up the Common Word Service setcomw
Syntax
setcomw(size, activity)
size: Number of bytes allocated to each station.
activity: Station activity with respect to the common words (0: inactive; 1: read/write; 2: read only).
Description
Sets up the common word service.
Operation
Function setcomw(..) must be called in task %INI. If this function is not called, the common word service is not active.
The same number of bytes must be allocated to each station in the network. If the value set for a station is incorrect,
this station is ignored by the other stations.
Since the stations can share a maximum of 256 words (512 bytes), the size chosen determines the maximum number
of stations that can use the common word service.
Size per station Max No. of stations Station addresses
8 bytes 64 0 to 0x3F
16 bytes 32 0 to 0x1F
32 bytes 16 0 to 0xF
64 bytes 8 0 to 7
128 bytes 4 0 to 3
An inactive station cannot send common words and cannot read those sent by the other stations.
A station active for read cannot send common words but can read the common words sent by the other stations.
A station active for read/write can send common words and read those sent by the other stations.
The stations declared active for read/write must have the lowest addresses on the network.
The number of common words configured can be less than the maximum authorised per station. This possibility should
be used when the volume of information to be sent is small. Processing of the common words by the automatic control
function is thereby improved.
Return Code
If OK
Code Report message
0x00 Setup OK
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