Rockwell Automation 1785-Lx6B,D17856.5.13 MNL. PLC-5 PROTECTED PROCESSOR - Manual (Page 29)

Chapter 3
Configuring DTE Protection
3-8
When processing each protection-screened command while protection is
enabled, the validation process checks to make sure that the:
• DTEP file
- exists
- is an integer file
• data-table file number is valid
• range of values in the DTEP file are valid
• file numbers exist
• starting/ending element value pairs are equal or in increasing order
• ranges represent words actually located in the indicated data-table file
If any of these is not the case,
• an error code ( DTE Protection File Invalid ) is returned
• a minor fault (S:17/12) is set
The value ‘-1’ is accepted to nullify an unused entry and is not detected as
an error. The ending element field can be set to ‘999’ regardless of the
number of elements actually in a file, and this is not detected as an error
when validating the protection file.
Important: Any invalid conditions prevent all attempts by an end user to
perform any DTEP-screened commands until the problem is corrected.
As system administrator, thoroughly test the DTEP file before implementing
it for the end user by following these steps:
1. Change your privilege class to one of the previously defined end-
user classes.
2. Attempt a write operation (data-table monitor) to a protected data-
table address.
This forces the validation of the DTEP file. If the file is not valid,
minor-fault bit S:17/12 is set and further write operations are prevented
until the file error is fixed. If DTEP is operating properly, an error code
(
Data Table Element Protection Violation ) is returned, and
minor-fault bit S:17/11 is set.
3. Attempt a write operation to a non-protected data-table address.
This operation should be successful.
4. Change your privilege class back to class 1, and fix any errors.
If you must go back and add further data-table elements to existing DTEPs
following integration of a system, first check to see that end users have not
already accessed any of the to-be-protected elements in their instruction
addressing. If you add protection to elements that have already been used,
you are, in effect, locking end users out of their own logic.
Testing the Protection File