Data type, Read/write, Data type read/write – Rockwell Automation 8520-9API 9/Series OCI API Developer's Guide User Manual

Page 50

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4–2

OCI Data Server Data Items

Publication 8520-6.6 - August 1999

The data type for a OCI data item determines how the data is
returned from the control to the OCI. You define variables according
to this data type. Requesting the wrong data type for a data item to
the control can return invalid data or an error. Valid data types
include:

DATA TYPE:

Description:

STRING

Alphanumeric string ranging from 0 to 65,535 characters

INT

Whole number ranging from -32,768 to 32,767

UINT

Unsigned integer

DINT

Double integer

UDINT

Unsigned double integer

LINT

Long Integer

SINT

Signed integer

USINT

Unsigned single integer

REAL

Real number

LREAL

Long Real

BOOL

Boolean (True/False)

R indicates the data is read only (passed from CNC to OCI). W
indicates the data is write only (passed from the OCI to the CNC).
R/W indicates the data is both read and write. Errors are generated if
you attempt to write data to a read only OCI data item.

Write privileges for commands and API data items are reserved for
the controlling OCI station. You must first successfully issue the
REQUEST_CONTROL command before write requests will be
accepted by the OCI station. Refer to the command chapter for
details on issuing the REQUEST_CONTROL command.

Data Type

Read/Write

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