Serial devices and the DeltaV system > Serial card data mapping

Mapping Modbus coils and input status

Modbus coils and input status values are both single-bit values. The Serial Card treats both types of values the same with regard to data mapping. The mapping details for each data type are described in the following table.

Table: Mapping Coil and Input Status Data to DeltaV Data Types

DeltaV Data Type

Mapping Method

Boolean

The card maps each coil or input status value directly to a single Boolean value with no data conversion.

Discrete, signed integer, unsigned integer, and floating point

The card sets the integer or floating point value to 0 if the coil or input status bit has a value of 0 or to 1 if the coil or input status bit has a value of 1.

String

Not supported.