Creating a Generic Data Group

The Allen Bradley EIE only includes "generic" data groups. Because associated field devices run custom programs, canned data groups are unfeasible. You must write your own data groups to suit your specific program needs.

CygNet SCADA provides a remote device editor to create and configure generic data groups. The remote device editor enables you to configure one or more blocks for inclusion in a data group. Blocks are simply collections of data file elements, including data file identifiers. Manually collect information like data file types and elements from the applicable field device program(s) before beginning to write data groups. You can upload an XML file that contains the data group definition of a single ABGeneric data group. Do so on a data group-by-data group basis using the Load from file option in a data group editor. You also might find it useful to save a defined data group to a file and view it in XML.

You could write a single data group that organizes all data for a remote device, but it is more appropriate to organize data into multiple smaller data groups. Breaking up data into smaller data groups enables your data groups to better reflect how data is grouped in a program and to more efficiently communicate with a field device. For example, one data group might contain elements that are polled every 15 minutes and another might contain elements that are polled once per hour or only on demand – you wouldn't want to poll all of that at once. Moreover, one data group might contain information indicating that it would best be grouped together because it shares a quality, such as file type.

For more information, see the following subsections:

• To Create a Generic Data Group
• To Parse Bits of a Word
• File Type Values

For more information about data groups, see Data Groups.

To Create a Generic Data Group

1. Open the applicable DDS, click Remote Devices, then double-click the applicable Allen Bradley remote device.
2. Create a new "AB Generic Data Group" (ABGeneric).
   1. In the remote device editor, click the Data Group page, then click Add.
   2. Select an "AB Generic Data Group," then click OK.
   3. In the Data Group Properties dialog box that appears, make settings edits to suit your needs, like providing a less generic Description value, then click OK.
   4. Repeat the steps above until you've created all the "AB Generic Data Group" instances you want.
3. Configure a new "AB Generic Data Group."
   1. If you are not there already, go to the Data Group page of the applicable remote device editor.
   2. For each "AB Generic Data Group" you created above, select the data group, then click Properties.
   3. In the Data Group Properties dialog box that appears, click Configure.
   4. In the Allen Bradley Data Group Definition dialog box that appears, click Add block.
   5. In the Add/Edit Block dialog box that appears, enter settings to suit your needs, then click OK. File block data group element IDs are created automatically in the following format: FxxxEyyyzz where xxx is the file number, yyy is the element or slot number, and zz is the sub-element number.
      • File #: SLC file-type numeric identifier. Varies by File Type value specified.
      • File Type: SLC file-type abbreviations. Only those supported appear in the list. See File Type Values.
      • Starting element: Element from which to begin collecting data for the specified file type.
      • Ending element: Element from which to stop collecting data for the specified file type. Ensure you know the maximum number of elements allowed for a selected file type. Some types, like C, include three fields per element – status, preset, and accumulator.
      • I/O slot: For an I/O file type (that is, I or O), specifies slot.
   6. When you are done, click OK at the Allen Bradley Data Group Definition dialog box, then at the Data Group Properties dialog box.
4. Optional: Parse individual bits of a word. See To Parse Bits of a Word.
5. Click OK to save, then poll the affected data groups and confirm retrieved values are correct.

To Parse Bits of a Word

1. In the Allen Bradley Data Group Definition dialog box, select an element from a block and click Edit element.
2. In the Edit Element dialog box that appears, click Add, then enter settings to suit your needs and click OK.
   • Bit field ID: The data group element ID (DEID). Max of 10 characters, no spaces. Valid characters are A-Z, 0-9, underscore, and dash. The first character must be a letter.
   • Description: User-defined bit description. Max of 32 characters, spaces allowed. Valid characters are A-Z, 0-9, underscore, and dash.
   • Starting bit position: Number of the starting bit to be parsed. The register is 0-based and is read from right to left (for example, bit 0 is the right-most bit in the word).
   • Number of bits: Number of bits to include in the bit field. Cannot exceed the data size. For example, if the starting bit position is 4 and the data size is a single byte, the maximum number of bits available is 4.
   • Display in hex: Option to display in hexadecimal.
3. Repeat the steps above for each element you want to parse bits from.
4. When you are done, click OK at the Allen Bradley Data Group Definition dialog box, then at the Data Group Properties dialog box.

File Type Values

The following table provides addressing values to be used when defining CygNet SCADA data groups that are mapped to SLC data files.

File Type #	Abbrev.	Name	Notes
0	O	Output	This file stores the state of the output terminals for the controller.
1	I	Input	This file stores the status of the input terminals for the controller.
2	S	Status	This file stores controller operation information. This file is useful for troubleshooting controller and program operation.
3	B	Binary, Bit	This file is used for internal relay logic storage.
4	T	Timer	This file stores the timer accumulator and preset values and status bits.
5	C	Counter	This file stores the counter accumulator and preset values and the status bits.
6	R	Control	This file stores the length, pointer position, and status bits for specific instructions such as shift registers and sequencers.
7	N	Integer	This file is used to store numeric values or bit information.
8	F	Float	This file stores single precision non-extended 32-bit numbers.
9 - 255	N/A	N/A	Can be any file type except I or O.