VIM Ethernet device configuration data

The following table lists the meanings of Special data values.

DeltaV Data Type

This attribute defines how data is stored in the DeltaV dataset. The following tables describes available options for PLC5/XXE, SLC 5XX, and ControlLogix processors.

Device Data Type

This attribute defines what type of transaction will be performed for the Dataset between the Serial Card and the Allen-Bradley device Values from 0 to 11 are listed in the above table. They are briefly described below:

Types 4 (Typed Transaction with ASCII addressing) and 8 (Typed Transaction with binary addressing):

The typed transactions treat each data type as an element and automatically adjust the memory address to accommodate the defined element type. Therefore, the starting address points to different memory location depending on the data type. It points to the word address for integer data and double word address for floating point data.

For Binary data type, it points to the word, not the bit, address within the Binary file. The number of element denotes the number of bits to be included in the Dataset starting at the specified word address. The bit position is relative to the starting word address. Therefore, every seventeenth bit will start at the next word. For example, a starting address of 8 with 32 elements means the Dataset starts at the eighth word in the binary file and contains 32 bits. The seventeenth bit will start at the ninth word. The bit position in the PLC is specified by a slash (/) after the word address. Therefore, the first bit in the above Dataset has an address of B3:8/0. Although each Dataset can contain 100 elements, it is recommended that the maximum number to be 96 to ensure the Dataset ends on a word address boundary.

Both single and block output modes are supported for integer, binary, and floating point file type.

Types 5 (Ranged Transaction with ASCII addressing) and 9 (Ranged Transaction with binary addressing):

Unlike Typed operations that automatically adjust the memory address to accommodate the defined element type, the Ranged operations use word address exclusively. It performs consecutive memory word read and write. The driver takes care of address adjustment for floating point file type, making it transparent to the user and DeltaV. Therefore, the Ranged operation on integer, binary and floating point file types is the same as the Typed operation.

Both single and block output modes are supported for integer, binary, and floating point file type.

Unlike the Typed read which only accesses the accumulator or position attribute, the Ranged read always starts at the first attribute and includes all three attributes in the data file.

Types 7 (Read-Modify-Write with ASCII addressing) and 10 (Read-Modify-Write with binary addressing):

When communicating with a PLC-5, Read-Modify-Write (RMW) is used to set/reset a single bit in the binary file. User can set any bit in the Dataset. It is different from writing to the binary file with Typed write. The Typed write will write all 16 bits in the word. The RMW let user write a single bit in any word, leaving other bit unaffected. The block output mode is not supported in RMW. Therefore, single output mode (1) must be used with RMW.

RMW is for output only. The data direction parameter in the Dataset configuration must be "output". Configuring RMW as input to Serial Card will cause error and undesirable results.

Type 11 (SLC 500, SLC 5/03 and SLC 5/04 Protected Typed Logical Read/Write with three address fields):

This DeviceDataType is used to read/write all available tables (including the Input and Output tables) of the SLC processors listed. The reads and writes are from/to the logical address generated based on the starting address of the dataset. The following describes the parameters and their usage:

Input, Output, and Binary tables can be defined as Boolean, Discrete or 16-bit UINT. When using Boolean or Discrete, the starting address is always a 16-bit word address (0, 16, 32, etc), and the Number of Values refers to bits. For example, a Dataset with starting address at 0 and 32 values gives you 32 bits. When using 16-bit UINT, the starting address can be anywhere in the table, and the Number of Values refers to 16-bit registers.

Input tables are read only. Output tables can be read and written. When performing reads/writes to the Output table, the driver will access the SLC on a 16-bit word basis. If the Output mode in DeltaV is 0 (i.e., Block), the entire block will be written if any bit in the Dataset changes. On the other hand, if the Output mode is 1 (i.e., Single Value), then on a single bit change, the 16-bit word containing that bit will be written.

For floating point values, the starting address refers to the register number and a 4-byte value is read/written. For all other tables, the starting address refers to the register number and a 2-byte value is read/written.

For information on how to connect I/O registers in a Logix controller to DeltaV datasets using Class1 and Class3 Ethernet/IP messaging, refer to the Mynah Ethernet/IP Master Driver for DeltaV Virtual I/O Module User's Manual.