Rockwell Automation Publication 1766-UM001O-EN-P - September 2021 125
Chapter 6 Real-Time Clock and Memory Modules
Program Compare
The memory module can also provide application security, allowing you to
specify that if the program stored in the memory module does not match the
program in the controller, the controller will not enter an executing (run or
test) mode. To enable this feature, set the S:2/9 bit in the system status file. See
“Status System File” in the MicroLogix 1400 Programmable Controllers
Instruction Set Reference Manual, Publication 1766-RM001
for more
information.
Data File Download Protection
The memory module supports data file download protection. This allows user
data to be saved (not overwritten) during a download.
Memory Module Write Protection
The memory module supports write-once, read-many behavior. Write
protection is enabled using your programming software.
Removal/Insertion Under Power
The memory module can be installed or removed without risk of damage to
either the memory module or the controller, except during a data transaction.
If the memory module is removed during a data transaction, data corruption
can occur.
If a memory module is installed while the MicroLogix 1400 is executing, the
memory module is not recognized until either a power cycle occurs, or until
the controller is placed in a non-executing mode (program mode, suspend
mode or fault condition).
Memory Module Information File
The controller has a Memory Module Information (MMI) File which provides
status from the attached memory module. At power-up or on detection of a
memory module being inserted, the catalog number, series, revision, and type
are identified and written to the MMI file. If a memory module is not attached,
zeros are written to the MMI file. See MicroLogix 1400 Instruction Set
Reference Manual, publication 1766-RM001
, for more information.
Program /Data Download
To download the program and data from a memory module to the controller’s
memory, on the “Comms” menu in your RSLogix 500/RSLogix Micro
programming software, point “EEPROM” and then click “Load from
EEPROM”.
Data file download protection is only functional if the processor does not have a fault,
size of all protected data files in the memory module exactly match the size of
protected data files within the controller, and all protected data files are of the same
type. See “Protecting Data Files During Download” in the MicroLogix 1400
Programmable Controllers Instruction Set Reference Manual, Publication 1766-RM001
.
IMPORTANT Once set, write protection cannot be removed. A change cannot be made to
the control program stored in a write protected memory module. If a
change is required, use a different memory module.
To Next Page
Loading...
