Nortel Networks DCT1900 Central Processing Unit CPU REX-BRD0004 or 2/ROFNB 157 19/2, Maintenance

Technical Product Manual - DCT1900

Installation Instructions, Central Processing Unit (CPU) – REX-BRD0004 or 2/ROFNB 157 19/2

CHAPTER 5

Central Processing Unit (CPU) – REX-BRD0004 or 2/ROFNB 157 19/2

5.1General

Maintenance

The CPU contains the following field–exchangeable parts (see Figure 5–4):

zCPU Firmware (Mobility) - RYS 105 447

zCPU Firmware (Standalone) - RYS 105 657

zCPU Firmware, Poll Processor - REX-SW0014 or RYS 105 663

zSync FPGA (Field Programmable Gate Array) - RYSNB 101 24

zLithium Battery (type DL2032)

The CPU firmware is delivered as a separate item.

The lithium battery is a back-up power supply for the Real Time Clock (RTC) on the CPU board. The RTC supplies the system date (year, month, day) and time (hours, minutes, seconds). If the lithium battery dies, the system will require UTAM activation whenever the CPU power is cycled unless it has been initialized as a non-UTAM system.

5.2Board Description

Functionality

The CPU board is used in both a Standalone (SA) system and in a Mobility Server (MS) system. The firmware that is resident on the CPU board determines which type of system the board will function in.

Firmware RYS 105 657 is for Standalone Systems

Firmware RYS 105 447 is for Mobility Server Systems

Synchronization

If the CPU resides in a system that is part of multiple system configuration, PWT interface and frame synchronization is required. When the PWT air interface is synchronized, efficient use of the network capacity and seamless handovers between systems are possible when the coverage areas overlap. To achieve PWT air interface synchronization in a multiple system configuration, the respective CPUs (responsible for the frame timing) have to be in sync. CPUs are synchronized using a master/slave concept, where one master CPU supplies a synchronization signal to a number of slave CPUs. A slave CPU can act as a master for a further three slave CPUs, thus creating a multi level star network with a maximum of two levels, see Figure 5-1.

Install-DCT1900/R8/mw	5-1
© 2000-2005