CTI 2572-A, Installation And Operation Manual

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CTI 2572-A Installation and Operation Guide
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7.2. Tag Types Supported
The following table lists the Tag Types supported by the 2572-A EIP server.
Tag
Type Description Tag
Name
Example
VS V Signed: Accesses a V memory register as a 16 bit signed integer VS2
VU V Unsigned: Accesses a V memory register as a 16 bit unsigned integer.
NOTE: The Control Logix processor does not support 16 bit
unsigned integer as a data type. (See VE Tag Type below)
VU335
VF V Float: Accesses a pair of V memory registers as a 32 bit floating point
number VF650
VL V Long: Accesses a pair of V memory registers as a 32 bit signed
integer VL50
VE V Extended: Converts between a V memory 16 bit unsigned integer and
a 32 bit signed integer CIP data element.
NOTE: This Tag Type is
specifically for controllers that do not support 16 bit unsigned
integers See the following section for more information.
VE1000
Figure 10. V memory Tag Types
V Extended (VE)
VE is a special Tag Type created for controllers that do not support the 16 bit unsigned integer data
type. For Data Table Read operations, it converts unsigned integers stored in a V memory register to a
32 bit signed integers that can be read by the client controller. For Data Table Write operations, it
converts one or more 32 bit signed integers sent by the client to a 16 bit unsigned integers, each
stored in a single V memory location.
The following restrictions are placed on data written to V memory using this Tag Type:
1. The value must be a positive number or 0.
2. The maximum value is 65,535 (0xFFFF).
Values that do not meet these requirements will be rejected by the 2572-A EIP server.
7.3. 2572-A Configuration
The EIP Server starts automatically when the module is started up. No additional configuration is
required.
7.4. Application Example
The following example illustrate how to configure a Control Logix system to communicate with the
2572-A. The example reads unsigned integers stored in V memory and writes a block of signed
integers to V memory.