Instruction manual

FUNCTIONAL DESCRIPTION

This section describes how the digital switch and the software of System 25 provide control and

switching.

Digital Switch

Figure 3-1 shows a block diagram of the System 25 digital switch. The basic switch hardware

consists of the following:

● Common Control

● Switching Network

—

COMMON

CONTROL

SWITCHING

NETWORK

Time Division Multiplex (TDM) Bus

Port Circuits

System Resource Circuits

CPU/MEM

TDM BUS

PORT

CIRCUITS

SERVICE

CIRCUIT

TONE

DETECTOR

POOLED

MODEM

TRUNKS, VOICE,

AND DATA TERMINALS

Figure 3-1.

SYSTEM RESOURCES

System 25 Digital Switch

November 1995

3-1