FDDI configuration management state machine controller

A physical layer controller for controlling the physical layer of a station that is suitable for insertion into a data transmission network that is capable of operating substantially in accordance with the fiber distributed data interface (FDDI) protocol, the physical layer controller including a configuration management entity that includes a configuration management state machine and is arranged to configure the physical layer controller substantially in compliance with the FDDI protocol, the physical layer controller further comprising:

• a current configuration register that dictates the configuration of the physical layer controller;
• a plurality of configuration data holding registers each arranged to store information indicative of a desired configuration of the physical layer controller when the configuration management state machine enters a predefined state associated with the configuration holding register, wherein each configuration data holding registers is arranged to be preloaded with configuration information indicative of an independent predetermined state and transmit at least a portion of its contents to the current configuration register when the configuration management state machine enters a state associated with that configuration data holding register, the configuration data holding registers each being arranged to independently load information into the current configuration register when the configuration management state machine is to be transitioned to a state associated with that particular register such that the physical layer controller can conduct a connection management sequence that requires the configuration management state machine to enter a plurality of states without requiring software intervention to write in a new configuration during the execution of the connection management sequence.

A physical layer controller for controlling the physical layer of a station that is suitable for insertion into a data transmission network that operates substantially in accordance with the FDDI protocol, the physical layer controller comprising:

• a configuration management entity that includes a configuration management state machine that is capable of configuring the physical layer controller substantially in compliance with the FDDI protocol;
• a port for receiving a pair of connectors for coupling the physical layer controller to an adjacent node in the data transmission network, the port having a port input and a port output;
• a plurality of channel connections for coupling the physical layer controller to a neighboring controller within the station, each channel connection having a channel input and a channel output;
• a transmitter having a transmitter output coupled to the port output and a transmitter input;
• a current configuration register that dictates the configuration of the physical layer controller;
• a read/write null configuration register for storing information indicative of a desired configuration of the physical layer controller when the configuration management state machine enters a null configuration;
• a read/write join configuration register for storing information indicative of a desired configuration when the configuration management state machine enters a join configuration;
• and
• a read/write loop configuration register capable for storing information indicative of a desired configuration when the configuration management state machine enters a loop configuration;
• wherein the null, join, and loop configuration registers are each arranged to transmit at least a portion of its contents to the current configuration register when the configuration management state machine enters a state associated with that configuration register.