Normal Data Transfer - ProSoft Technology MVI69-GSC CompactLogix User Manual

MVI69-GSC ♦ CompactLogix or MicroLogix Platform
Generic ASCII Serial Communication Module
All data transferred between the module and the processor over the backplane is
through the input and output images. Ladder logic must be written in the CompactLogix
processor to interface the input and output image data with data defined in the Controller
Tags. All data used by the module is stored in its internal database. The following
illustration shows the layout of the database:
Module's Internal Database Structure
5000 registers for user data
3000 words of configuration and
status data
Data contained in this database is paged through the input and output images by
coordination of the CompactLogix ladder logic and the MVI69-GSC module's program.
Up to 60 words of data can be transferred from the module to the processor at a time.
Up to 60 words of data can be transferred from the processor to the module. The read
and write block identification codes in each data block determine the function to be
performed or the content of the data block. The block identification codes used by the
module are listed below:
Block Range
0 to 127
9998
9999
Each image has a defined structure depending on the data content and the function of
the data transfer.

Normal Data Transfer

Normal data transfer includes the paging of the user data to and from the module's ports
and bringing in status data. These data are transferred through read (input image) and
write (output image) blocks. The structure and function of each block is discussed in the
following topics:
ProSoft Technology, Inc.
Descriptions
Normal Data Blocks for Read and Write
Warm-boot control block
Cold-boot control block
Register Data
Status and Config
0
4999
5000
7999
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