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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 are 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 PSIC 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.

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