Associated with: Many items on the Simple Modbus driver
The Source attribute is common to many Status displays. The attribute indicates the location at which the item resides. The information shown varies, depending on the item.
The Source attribute displays the value Undefined if the item’s configuration is incomplete, in so far as the device with which the item is associated has not yet been specified.
The examples below assume that Modbus addressing starts at 1, rather than 0. (For examples and explanations as to how Modbus addressing is configured in ClearSCADA, see Configuration Examples.)
For scanners that are using TCP/IP communications, information is displayed in this format:
MODBUS/TCP-<Host Address> <Port>: Device <Address>, <Location> - <Location Digit>:<Address>
(For an address range, two location digits and addresses are shown.)
Example:
MODBUS/TCP-10.1.5.30 502:Device 5, Input Registers - 3:00003-3:00006
(For a scanner that has a Device Address of 5, and is used to retrieve data from the input registers at addresses 300003 to 300006. The scanner is using TCP/IP networked communications, to communicate with Host Address 10.1.5.30, via Port 502.)
For scanners that are using serial communications, information is displayed in this format:
<Port>:<Baud Rate>:<Data Bits><Parity><Stop Bits>-<Host Address> <Port>: Device <Address>, <Location> - <Location Digit>:<Address>
(For an address range, two location digits and addresses are shown.)
Example:
COM1:9600:8N1-8 502:Device 5, Output Coils - 0:00003-0:00006
(For a scanner that has a Device Address of 5, and is used to retrieve or send data to the output coils at addresses 00003 to 00006. The scanner communicates with Host Address 8, via Port 502, using a channel that has these properties: the channel communicates via port COM1 using a baud rate of 9600, with 8 data bits, no parity (N), and 1 stop bit.)
For points that are on scanners which are communicating using TCP/IP communications, information is displayed in this format:
MODBUS/TCP-<Host Address> <Port>: Device <Address>, <Location> - <Point Type> <Location Digit>:<ClearSCADA address> (<Data Type (for analog points only)>)
(For an address range, two location digits and addresses are shown.)
Example:
MODBUS/TCP-10.1.5.30 502:Device 5, Input Registers - AG 3:00010 (UINT)
(For an analog point that represents the unsigned 16-bit (UINT) data from input register address 30010. The device address and communications details are as per the scanner example, above.)
MODBUS/TCP-10.1.5.30 502:Device 5, Holding Registers - AG 4:00009-4:00010 (REAL)
(For an analog point that is used for passing IEEE floating point values (REAL) to the holding registers at addresses 400009 and 400010.The device address and communications details are as per the scanner example, above.)
For points that are on scanners which are communicating using serial communications, information is displayed in this format:
<Port>:<Baud Rate>:<Data Bits><Parity><Stop Bits>-<Host Address> <Port>: Device <Address>, <Location>:<Point Type> <Location Digit>:<ClearSCADA address> (<Data Type (for analog points only)>)
(For an address range, two location digits and addresses are shown.)
Example:
COM1:9600:8N1-8 502:Device 5, Output Coils - DG 0:00043
(For a digital point that represents output coil address 00043. The point is located on the Modbus scanner that has a Device Address of 5. The device address and communications details are as per the scanner example, above.)
The Source attribute displays the type of Modbus point using these abbreviations:
| Abbreviation | Point Type |
|---|---|
|
DG |
Digital point |
|
AG |
Analog point |