Access Control - GE PACSystems RXi User Manual

Chapter 4. Configuration
4.1.7

Access Control

The Access Control list allows you to specify the reference address ranges that can be
accessed by non-local devices such as HMIs and other controllers. To use this feature,
Enhanced Security must be enabled in the target's properties.
When Enhanced Security mode is enabled, any reference address range not defined cannot
be accessed by other devices. External reads and writes that do not exist in the table are
rejected by the firmware.
If overlapping memory ranges are defined, they must have the same Access level.
For symbolic variables, access control is specified by the variable's Publish property, which
includes a Read Only and Read/Write setting.
Note:
Access Control List Settings
Memory Area
Start
End
Access
46
When requesting data from an external device, some drivers packetize data to
optimize communication. If a request attempts to read a value that is not published,
the entire packet will fail. A fault has been added to the fault table to help you
understand a failed read/write. After addressing the fault, you must clear the fault in
order to try again.
The memory area in which the reference address range is defined.
Default: Select an Area
Choices: %AI Analog Input, %AQ Analog Output, %I Discrete Input, %G Genius Global,
%M Internal Discrete, %Q Discrete Output, %R Register Memory, %S System,
%SA System, %SB System, %SC System, %T Temporary Status,
%W Bulk Memory.
The starting offset of the reference address range.
Default: 0 (not valid)
Valid range:
For %S, %SA, %SB and %SC, must be 1.
All other memory types: 1 through the upper limit of the reference address range.
Must be less than the End value.
The ending offset of the reference address range.
Default: 0 (not valid)
Valid range:
For %S, %SA, %SB and %SC, must be 128.
All other memory types: Any value greater than Start, through the upper limit of the
reference address range.
For word memory types (%AI, %R and %W) the highest address available is configured on
the Memory tab.
Selects the type of external access allowed for the defined address range.
Choices: Read-Only, Read/Write
Default: Read-Only
PACSystems* RXi Distributed IO Controller User Manual GFK-2816F