Cabletron Systems FDDI Repeater manual System Management Bus, System Diagnostic Controller

Operation

System Management Bus

There are two management channels within the MMAC-Plus system: the SMB-1 and the SMB-10. These buses provide out-of-band management and inter-module management communication. The 9F206-02 uses only the SMB-1 bus.

The SMB-1 is a 1 Mbps management bus located within the MMAC-Plus. This bus is utilized by all diagnostic controllers in the system including connectivity modules, power supply modules and the environmental module. The SMB-1 transports inter-chassis information between system components, such as power and environmental information, as well as diagnostic messages.

System Diagnostic Controller

This diagnostic controller is composed of a Z-80 microprocessor and its supporting logic. The diagnostic controller is designed to control the power-up sequencing of modules, monitor the 9F206-02 input and output parameters, as well as monitor the temperature, and control the SMB LANVIEW LED. The diagnostic controller on the 9F206-02 is also responsible for reporting the FNB and front panel connectivity status to network management. The information gathered by the diagnostic controller is available to the network manager via local/remote management and the LCD located on the Environmental Module. The 9F206-02 has been designed so that in the event of a diagnostic controller fault, the 9F206-02 will continue to function.

DC/DC Converter

The DC/DC converter converts the 48 VDC on the system power bus to the necessary operating voltages for its host network services module. The diagnostic controller controls the operation of the DC/DC converter.

FNB Interface

MMAC-Plus modules are designed with one of two attachment policies. One allows a module to dual attach to either FNB-1 or FNB-2; the second allows dual attachment to both FNB-1 and FNB-2. The 9F206-02 has dual attachment to the FNB backplane, connecting to both FNB-1 and FNB-2. These flexible configuration options make the MMAC-Plus ideal for networks designed to Bridge/Route multiple lower speed LANs to FDDI and/or networks designed using an FDDI collapsed backbone.

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