Allen-Bradley MicroLogix 1200 Reference Manual page 41

Access the Download Data File Protect feature
using RSLogix 500 programming software. For
each data file you want protected, check the
Memory Module/Download item within the
protection box in the Data File Properties
screen as shown in this illustration. To access
this screen, right mouse click on the desired
data file.
User Program Transfer Requirements
Data File Download Protection only operates when the following
conditions are met during a User Program or Memory Module download
to the controller:
• The controller contains protected data files.
• The program being downloaded has the same number of protected
data files as the program currently in the controller.
• All protected data file numbers, types, and sizes (number of elements)
currently in the controller exactly match that of the program being
downloaded to the controller.
If all of these conditions are met, the controller will not write over any
data file in the controller that is configured as Download Protected.
If any of these conditions are not met, the entire User Program is
transferred to the controller. Additionally, if the program in the controller
contains protected files, the Data Protection Lost indicator (S:36/10) is set
to indicate that protected data has been lost. For example, a control
program with protected files is transferred to the controller. The original
program did not have protected files or the files did not match. The data
protection lost indicator (S:36/10) is then set. The data protection lost
indicator represents that the protected files within the controller have had
values downloaded and the user application may need to be
re-configured.
The controller will not clear the Data Protection Lost
NOTE
indicator. It is up to the user to clear this bit.
Controller Memory and File Types
Publication 1762-RM001C-EN-P
2-7