Data Type Coercion

To ensure the highest throughput of point values through the GagePort Mitutoyo OPC Server to an OPC Client, the client should always request the canonical data type of an attribute.


The following table shows data types that should be requested based on the value source with example variant types.

Client Requests
Values from a:

Should request
the values as:


Variant Type

GPFP gage hub

Four-byte REAL


MIG2 gage hub

Four-byte REAL


SIMPLE serial device



By requesting a point in canonical form, the OPC Server does not have to coerce (or convert) between the data type stored internally and the data type requested by the OPC client.

The OPC Server provides coercion support for all non-array OPC items. The OPC Server utilizes standard Microsoft coercion support routines. A drawback to relying on coercion is the penalty of extra processing overhead required for each transaction. However, relying on coercion in the OPC Server may simplify the OPC client or provide the user with the ability to select the data type most applicable.

More information

GagePort Mitutoyo OPC Server data types.