Avaya Octel 200, Octel 300 Octel 200/300 Motherboards

2-14 Installationand Maintenance Volume
Octel 200/300 S.4.1 PB60019−01
Octel 200/300 Motherboards
The motherboard distributes power to the cards, disks, and fans; provides signaling between slots;
interconnects cards and external connectors; and has a reset signal that activates when the power is
turned on (resetting all boards in the message server.)
Motherboards are installed in the rear of the server cabinet.
-The Octel 200 has one motherboard located behind shelves A and B.
-The Octel 300 has three motherboards, one located in each shelf: A, B, and C.
The shelf A motherboard has two flat ribbon cables. One connects to the Works drive in slot B2.
The other flat ribbon cable connects to the drives in slots B3 through B5.
The shelf B motherboard has one flat ribbon cable that connects from slot B3 to slot C4.
External Connections
The motherboard interconnects signals from cards installed in slots to respective external circuit
connectors. For example, an LIC installed in slot A1−A7 connects to tip-and-ring circuits of a
telephone network through rear connector P1−P7 in the Octel 200. For the Octel 300, A1−A11
connects to P1−11.
System/Voice SCSI Bus and Works SCSI Bus
The motherboard has signaling for two separate SCSI buses: the system/voice SCSI bus and the
Worksfor Serenade SCSI bus.
In the Octel 200, the System/VoiceSCSI Bus interconnects drives in slots B2 through B4. The Works
for Serenade SCSI bus connects to the drive in B1.
In the Octel 300, the System/VoiceSCSI Bus interconnects drives in slots B3 through C4. The Works
for Serenade SCSI bus connects to the drive in slot B2.
SCSI ID Field
The motherboard includes an ID signal field for each slot. ThisID field is used by the plug-in disk
assemblies for SCSI bus ID selection. Each SCSI device requires a unique SCSI ID. This signal is
used by the drive assemblies to select a unique SCSI ID.