Chapter 3. CPU ConfigurationGFK-2222AD April 2018 1313.2.13 Access ControlThe Access Control List allows you to specify the reference address ranges that can be accessed bynon-local devices such as HMIs and other controllers. To use this feature, Enhanced Security must beenabled in the properties of the target.When Enhanced Security mode is enabled, any reference address range not defined cannot be accessedby 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 Publish property of the variable, which includesa Read Only and Read/Write setting.Note: When requesting data from an external device, some drivers packetize data to optimizecommunication. If a request attempts to read a value that is not published, the entire packetwill 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.Access Control List SettingsMemoryAreaThe memory area in which the reference address range is defined.Default: Select an AreaChoices: %AI Analog Input, %AQ Analog Output, %I Discrete Input, %G Genius Global,%M Internal Discrete, %Q Discrete Output, %R Register Memory, %S System, %SASystem, %SB System, %SC System, %T Temporary Status, %W Bulk Memory.Start 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 lessthan the End value.End 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 referenceaddress range.For word memory types (%AI, %R and %W) the highest address available is configured on theMemory tab.Access Selects the type of external access allowed for the defined address range.Choices: Read-Only, Read/WriteDefault: Read-Only
