Should DeviceConnected() be called for each check scanner?
The first plug-in function that gets called is AreDevicesAttached().
Since it returns what is essentially a yes or no answer, it presumably
only reports that one or more devices are found to be available
(attached) but not how many. If it returns DeviceStatusAttached, then Ranger later calls InitializeDevices(). Then in the InitializeDevices() function, should the plug-in call DeviceConnected() for each device that it finds currently connected?
Yes, DeviceConnected() should be called for each scanner.