CIP Driver Tags

The CIP (Control and Information Protocol) driver tag type is included in VTS version 7.5 and later. These tags provide an interface between VTS and hardware that uses the CIP and/or ENIP standards for communications.

Notes About Allen Bradley Control Logix Tags

The ControlLogix family of PLCs use tag names to identify data objects in the PLC. The type of data object must be specified when writing to a particular tag. The ControlLogix family of PLCs supports the following atomic types:

•    Boolean (BOOL)

•    8-bit Signed Integer (SINT)

•    8-bit Unsigned Integer (BYTE)

•    16-bit Signed Integer (INT)

•    132-bit Signed Integer (DINT)

•    32-bit Unsigned Integer (DWORD)

•    32-bit Float (REAL)

 

In addition, 2-dimensional arrays are supported, thus an array of any type listed above is possible:

•    DINT[32] – a 32-element array of DINTs.

 

The ControlLogix family of PLCs also supports a structure. A structure is a collection of these atomic types. For example, a Timer has the following fields:

•    Timer.PRE – DINT

•    Timer.ACC – DINT

•    Timer.EN – BOOL

•    Timer.TT – BOOL

•    Timer.DN – BOOL

•    Timer.FS – BOOL

•    Timer.LS – BOOL

•    Timer.OV – BOOL

•    Timer.ER – BOOL

 

The VTS driver can read and write to all of the atomic data types within the structure. The VTS driver can also read a stream representation of a structure; it does not have any knowledge of the contents of the structure. At present, the driver cannot write an entire source.

It should be noted that even the atomic data types are themselves structures (of a special sort that can be read and written). For example, an INT is actually an array of 16 BOOLS, 1 representing each bit in the INT. It is possible to read and write a bit of an INT by addressing it correctly (i.e. INT_TAG1|INT will write to the least significant bit of INT_TAG.).

The characteristics of the CIP driver tag type are described in the table below.

CIP Driver Characteristics

Tag Browser Name: CIP Driver

Database Table Name: CIPENIPDriver

Type: Driver

Tag Group Memberships: Drivers, Numeric

Log Enabled Variables:  see Communication Driver Log-Enabled Variables

Native Drawing Methods: CIP Driver Tag Drawing Methods