Human Interface Devices (HID) can be polled for data. An HID is a USB-connected peripheral device such as a scanner (generally for barcodes or QR codes).
In the context of LoopEdge, the following characteristics are relevant for this serial device:
- The HID remains disconnected because HIDs send data only when there is data to send.
- Only one tag is required in order to read the data.
- Any register name can be added to the tag.
- By default, the polling interval is set to -1.
- Data can be collected onto flows when it is scanned.
Certain device drivers will not have a list of register names in the DeviceHub Add Tag form. These are Free Tag PLCs. For Free Tag requirements, see Troubleshoot Device Connectivity Status.