The preferred setting for the checkLink attribute is yes,
to enable early detection of missing or powered-down devices.
However, this detection does not work with three-wire connections.
To determine if the yes setting can be used, do the following:
- Set checkLink to yes.
- Attempt to link to a device that is known to be active (connected
to the port, powered-on, and ready to link).
- If the active device is incorrectly reported as being missing or
powered-down, then change the checkLink setting to no.