Technical Overview
3-4
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 modules’ input and output power
parameters, keep watch over the main host processor, monitor the temperature,
and control the SMB LANVIEW diagnostic LEDs. Although the system diagnostic
controller and the main host processor can operate independently of each other if
needed, they exchange information about each other’s status and overall module
condition. The information gathered by the diagnostic controller is available to
the network manager via local/remote management and the LCD located on the
environment module. The modules are designed to continue functioning in the
event of a diagnostic controller fault.
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 monitors and controls the operation of the DC/DC converter.
INB Interface
Each module attaches to both INB A and INB B and has two INB ASICs. The INB
ASICs use 64 byte Ethernet frames for transmission onto the INBs at 66 MHz.
The 9X5XX modules are fully compatible with the the first generation 9X4XX
modules. The first generation modules communicate only on INB B using a
56 byte canonical frame format, at 40 MHz. If the newer module detects a first
generation module on the backplane, it automatically changes from the fast
66 MHz Ethernet frames, to the first generation compatible 40 MHz canonical
frame on INB B only. INB A is used only by the 9X5XX modules and remains at
the higher speed.
i960 Core
The i960 core provides modules host services, the SNMP protocol stacks, to
support industry standard MIBs, as well as Cabletron enterprise extension MIBs
for each media type. Management services, such as telnet, WebView and network
address to MAC address mapping, are also provided by the i960 core.
