Method and apparatus for arbitration among multiple ports

A device has first circuitry and also second circuitry that includes an interface and command ports that can each receive commands from the first circuitry, each command requesting an information transfer through the interface. A technique relating to the device involves dynamically enabling and disabling at least one of the command ports under control of the first circuitry, and using a priority list specifying an order of priority for a group of the command ports to identify and cause a command to be accepted from the command port of highest priority that contains a command and is currently enabled.