System information

General Reference Guide IO Servers Configuration
RG-001-0-EN ver 1.5 eWON® - 20/03/2009 - ©ACT'L sa Page 128
Examples
• Bit access modifier:
In any Memory Type (excluding Counter and Timer), it is possible to access a single bit.
A #x must be appended to the Value name.
As the address is always in byte, the Bit index goes only from 0 to 7, no Modifer are allowed (except B to separate DB block from the
address).
The syntax can be used for reading bits and for writing them as well.
Example:
DB1B13#3 represents bit 3 of Byte 13 in DB 1
invalid: IW5#2 wrong because there is a Modifier
I5#10 wrong because bit number greater than 7
• Status register:
The STATUS Tag is a special Tag that returns information about the current state of the communication for a given device. As for other Tags, the
status Tag ValueName is composed of:
Status, Global Device Address
• You can define a status Tag for each PLC used.
• If you use the status address, the Tag must be configured as analog.
5.12.3.2 Global Device Address
The device address is either appended to the ValueName in the Item Name definition or entered in the Topic global address fields.
address point to
MW4 the Word at address 4 (in bytes) in the Internal Memory
CS1 the Counter number 1, read it as Signed Word
DB2L5 the DWord at address 5 (in bytes) in the Data Block 2
IB3 the Byte at address 3 (in bytes) in the Discrete Inputs zone
I5#2
the bit 2 from the Byte (read ‘Bit access modifer’ note below) at address 5 in
the Discrete Inputs zone
Table 102: S7 300-400 register address examples
0
Communication not initialized. Status UNKNOWN.
If no Tag is polled on that device address, the communication status is unknown.
1 Communication OK.
2 Communication NOT OK.
Table 103: Tag Status meaning