Item Name Syntax
DeviceName.Address[index]*, Datatype, LowRaw, HighRaw,
LowEng, HighEng,RequestedDataType
Everything after the Address is optional.
| Device Name |
Name of the Device |
| Address |
Protocol specific variable name |
| [index] |
Specify array.
eg. device1.40001[10] is a ten element vector,
device1.40004[10][10] is a 10x10 array.
If no index is specified than only one item is defined. |
| Datatype |
Possible raw data types are
| BOOL |
Boolean (1 bit) |
| I1 |
Signed byte (8 bits) |
| UI1 |
Unsigned byte (8 bits) |
| I2 |
Signed word (16 bits) |
| UI2 |
Unsigned word (16 bits) |
| I4 |
Signed long (32 bits) |
| UI4 |
Unsigned long (32 bits) |
| BSTR |
Variable Length String |
| I8 |
Signed Large (64 bits) |
| UI8 |
Unsigned Large (64 bits) |
| R4 |
Short floating point (32 bits) |
| R8 |
Long floating point (64 bits) |
|
| Low Raw |
Low limit of data from PLC |
| High Raw |
High limit of data from PLC |
| Low Eng |
Low limit of data from User |
| High Eng |
High limit of data from User |
| Requested Data Type |
Convert raw data type to the requested data type |
The LowRaw,HighRaw,LowEng and HighEng are optional and are
used to specify the scaling to be performed when reading and
writing to the PLC. e.g. Modbus0.40001,,0,9999,0,100 to scale the
variable to display percentage.
Adding Tags
There is usually no need to add tags at the server. The
whole data address space of the device is always directly
addressable. e.g. If you have a Modbus device 'Modbus1' and you
want to access 40002. Use the itemID modbus1.40002. The access
path is not used. Use the built in OPC explorer to connect to
IOServer. You will see the addressing format for the device via
the browse interface when you try to add an item to a group.
If the user wants to enforce their own naming convention, they
can drag and drop tag definitions into the "Tags List"
folder in IOServer. Click on the "Tags List", then drag your tags list from Wordpad, Word
or any drag and drop enabled application and drop it into the
Tags List folder. To export data from IOServer press the CTRL
key, left mouse click the folder and drag it into your document.
For Tags List, the first column is the user tag name, the second
column is the variable name. All user defined tags are grouped in
the "Tags" device.
eg. to configure your Tag List.
Use wordpad.exe (or Word) to type in your tag list
Tag1 Modbus1.40001
Tag2 Modbus1.40002
Tag3 Modbus1.40003
Tag4 Modbus1.40004
Click on the Tags List folder in IOServer. Select the above
four lines drag them to the Tags List folder in IOServer.
IOServer should now have the 4 User tags defined.
From Excel you should be able to see the following tags
IOSDDE|Group!'Tag1'
IOSDDE|Group!'Tag2'
IOSDDE|Group!'Modbus1.40005'
IOSDDE|Group!'Modbus1.30001'
The "Tags." prefix may be omitted when using
tags from the tags list.
Tag Browsing
IOServer can access the whole address space of a device. Instead of
enumerating all possible variable address in the device, IOServer use a hint
system to show the user what address range and type is possible for all the
possible addresses of a device.
examples
| %05u(1-65536) |
Expect a five digit decimal number between 1 and 65536 |
| %02u(1-32) |
Expect a 2 digit decimal number between 1 and 32 |
| %01u(1-8) |
Expect a 1 digit decimal number between 1 and 8 |
| %u(0-65535) |
Expect a decimal number between 0 and 65535 |
| %u(0-255) |
Expect a decimal number between 0 and 255 |
| %u(7-999) |
Expect a decimal number between 7 and 999 |
| %o(0-277) |
Expect an octal number between octal 0 and octal 277 |
| %x(0-1fff) |
Expect a hexadecimal number between 0 and 1fff |
If IOServer->Preference->Verbose Browse Item Info is enabled, then the
description, data type and access rights for each variable type is available.
System Device Variables
These variables are available in every device.

| Status |
Return a value of 0 if the device is offline. A value of 1
if the device is online. Writing a 0 to this variable will cause the
parent port to be disconnected. Writing a 1 to this variable will cause
the parent port to reconnect. |
| Comms |
Port Communication Statistics. Statistics Error to CharRx
can be reset to 0 by writing any value to that variable. Individual device
statistics are not available.
| Error |
Number of communication errors |
| CRCError |
CRC/Checksum error detected |
| Timeout |
Number of timeout |
| Retry |
Number retries attempt |
| FrameTx |
Number of frames transmitted |
| FrameRx |
Number of frames received |
| CharTx |
Number of characters transmitted |
| CharRx |
Number of characters received |
| Bandwidth |
% Bandwidth usage of port. |
| TimeOffset |
Time difference in microseconds between IOServer
internal clock and operating system clock. Use Long to read this
variable. |
| Bytes Used |
Total number of bytes by all OPC Clients |
| DeviceTx |
Number of frames transmitted by device |
| DeviceRx |
Number of frames received by device |
| Interface |
Local IP address |
| IP |
Remote IP Address |
| Telephone |
Telephone number of active outgoing call.
| Value |
Meaning |
| Phone Number |
Connected to this number |
| Negative number |
Connecting to this number |
| 1 |
DCD asserted with no current outgoing call |
| 0 |
Not connected |
|
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Using IOServer with Wonderware Intouch
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