CMVETH01B
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Cyclic Data Access
2. Click [Download] to download the configuration to the controller. When the download is successfully
completed, RSLogix enters online mode and the I/O OK box in the upper-left part of the screen is green.
3. On the top toolbar, click [File] then select [Save] from the pull down menu. If this is the first time the
project is saved, then the [Save As] dialog box will open. Navigate to a folder, type a file name and then
click [Save] to save the configuration to a file on your computer.
5.4 I/O Assemblies
SMV Ethernet/IP implementation supports the I/O assembly object class 0x04. SMV assemblies are static.
There are several Input and Output pre-defined assemblies (assembly object instances) that can be used
for data exchange. The terms Input and Output refer to the point of view of the scanner. Output data
is produced by the scanner and consumed by the adapter. Input data is produced by the adapter and
consumed by the scanner. The SMV is always an adapter device. Depending on the assembly number the
memory map of the data can have a different size and meaning.
5.4.1 Important Note on Input Assemblies
Input assemblies (adapter to scanner) are mapped to the adapter memory from byte 0. There is no preceding
4 byte header like that found in most Allen-Bradley equipment. The SMVector does not use preceding
header functionality for real time status. So the start address in the assembly memory map is the actual
start of the 1st assembly data item. The user should supply the actual assembly length when mapping the
input assembly to the controller memory.
5.4.2 Important Note on Output Assemblies
Output assemblies (scanner to adapter) are assumed to have the preceding 4 byte header. When mapping
the assembly this header will automatically be added to the data stream by most AB PLC/CLC equipment.
If you use equipment other than AB for the scanner, configure it to send the 4 byte header preceding the
actual assembly data. The data in the header should be set to 0.
5.5 Using Assemblies for Control and Status/Data Monitoring
Output assemblies are commonly used for controlling the enable/disable state of the drive and for supplying
the velocity or torque reference. Input assemblies are commonly used to monitor the drive status and run-
time quantities such as current velocity, current, actual position and position error. The recommended
configurations for I/O assemblies are:
Configuration assembly:
use assembly 1 with size 0
Status Output assembly:
use assembly 109
Status Input assembly:
use assembly 70, 71 or 106; size of assembly must match the actual size
of the assembly. In case of CompactLogix it must be 2 x 16bit.
