Rockwell Automation 1746-BLM Blow Molding Module Installation Instructions - Manual (Page 6)

6 Blow-molding Module
Publication 1746-IN014B-EN-P - January 2001
Communication with the SLC Processor
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shared memory
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control bit/status bit handshake
•
micro processor
•
PID control algorithm
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digital I/O
•
analog I/O
Shared memory
From the ladder programmer’s perspective, communication with the module is via
five data files located in shared memory on the module:
Config(G) File contains information regarding the operational mode and feature
settings of the module. You specify the contents of this file with
the ladder logic programming utility (RSLogix500). Entries in the
file are static and read-only from the module’s perspective (e.g.
time vs. position based operation). This file is automatically
downloaded to the module when you switch the SLC processor
to Run mode.
Output File contains 32 16-bit entries used by ladder program to command
module operation. The Output File may also be used to supply
process data to the module in certain situations. Entries in this
file are updated automatically, at the end of each scan, by the
SLC processor from the user data file but may be written at any
time by immediate I/O instructions in the ladder program.
Input File contains 32 16-bit entries used by ladder program to extract
status information from the module. The Input File contains
acknowledge bits corresponding to control bits in the Output
File, as well as information pertaining to the profile executing on
each analog I/O channel (step number, setpoint, analog input,
process variable, control output, etc.) and a parameter error flag.
The entries in this file are read automatically, once per scan, by
the SLC processor into the user data file, but may be read at any
time by immediate I/O instructions in ladder program.