Define Required A-variables
Add BR , EG , UT , and DS setting A-variables using AGG library's configurator . You should end up with a setting table as shown below:
Note that Reference Library (Settings) must be enabled and correct setting configurator file must be specified (settings.xtxt ). We are sure you will quickly find your way around the AggreGate configurator. Let's just briefly review some things worth noting. Double-click on the BR A-variable line — the Edit (A-variables) dialog will open.
• On the General tab, notice that the A-variable is Linked to the Settings Library . The Variable Name drop-down contents reflect available settings. Your A-variable is basically a "propagated" setting! You can also link to tables — this will be our next step's task .
• Notice also that the A-variable is Readable and Writable . All our A-variables are, except DS , which is only Readable (read-only).
• Description is set to Baudrate , and this is how this A-variable is visible in AggreGate.
• The Group is set to Access Control . This is where the Access Control tab you see in the AggreGate client comes from. The client will create separate tabs for all groups encountered. We only use one custom group in this project.
• Now switch to the Advanced tab and press Edit . Don't we have a lot here!
• Notice how the Field Type is Integer . The AggreGate server supports a different type set, and byte isn't on the list. The nearest suitable type is selected, which is integer .
• Selection Value is enabled and if you click ... you will see the whole list. Now you know where the drop-down selector on the Baudrate A-variable comes from.
• Maximum Limit will not allow you to set anything above 13 .
• There are numerous other fields we haven't touched. Explore and you shall discover!
Moving now to the remaining A-variables, and only touching on the notable differences:
• The EG A-variable has its Field Type = Boolean .
• The UT A-variable is limited to 127.
• The DS A-variable has two custom Selection Values (opened and closed ). it is only Readable , and not Writable .