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Ports that have USB devices connected to them will include a fid (Friendly ID) value (only array and XML-string returns include this value). Use the fid to determine which physical port on the player the USB device is connected to. The following table matches fid values to the ports on different model lines:
| Model Family | Friendly ID (fid) | Location |
|---|---|---|
| LS423 | A | Front (USB-C) |
| HDx23 | A | Front (USB-A) |
| HS123 | A | N/A (M.2 connector) |
| HO523 | A | Upper Front (USB-A) |
| B | Lower Front (USB-A) | |
| C | Back (JAE TX-25) | |
| XDx33/XDx34 | A | Front (USB-C) |
| B | Back (USB-A) | |
| XTx43/XTx44 | A | Back (USB-A) |
| B | Front (USB-C) |
A fid value of <port>.<int> (e.g. "B.0") indicates that the USB device is directly connected to the player, while a value of <port>/<int>.<int> (e.g. "A/4.2") indicates a device connected through a USB hub. The last integer specifies the endpoint: For example, if a USB device presents as both an HID and audio device, they will be listed as separate devices with different endpoint numbers. Also note that there can be more than one layer of port numbers if multiple USB hubs are connected together (e.g. "A/4.0.0").
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