System Technology; Pulse Code Modulation; Custom Electronic Circuitry; Stored Program Control - Toshiba Strata DK14 General Description Manual

System Technology

Pulse Code Modulation

Digital switching talkpaths enable all CO and intercom lines to be accessed simultaneously.
Analog-to-digital and digital-to-analog conversion is done by CODECs (coder plus decoder) on
station and CO line PCBs.

Custom Electronic Circuitry

Large Scale Integration (LSI) technology enables the Strata DK40i circuit designs to be simple and
efficient. Gate arrays using very large scale integration save vast amounts of space by using the
latest technology. More circuitry fits onto smaller PCBs for a more compact system. Widespread
use of CMOS circuits minimize system power requirements.

Stored Program Control

The system uses a 16-bit microprocessor for stored program control. Strata DK40i system
operating software is stored on Read Only Memory (ROM), and individual configuration and
custom programming is stored on Random Access Memory (RAM). A lithium battery with a life
span of at least six years preserves RAM in the case of a power failure.

Microprocessors

The system's main microprocessor is a 16-bit 68000-type that operates at a clock speed of 8 MHz.
In addition, some PCBs use 8-bit, TMP90C840-type local microprocessors that run at 10 MHz.
This distributed microprocessing architecture is used system-wide.

Maintenance and Programming

Hardware maintenance and repair procedures describe how to quickly locate, remove, and replace
defective parts and PCBs. System programming can be performed without taking the system out-
of-service.
On-site programming can be executed with any 20-button proprietary Liquid Crystal Display
(LCD) telephone or with a DKAdmin PC connected to an optional maintenance port.
Off-site programming with DKAdmin, which can help cut costs and save time, is available
through a customer-provided modem connected to the maintenance port. DK40i (only) provides
an optional built-in modem for remote administration and maintenance.

DKAdmin/DKBackup

Toshiba DKAdmin software Release 4.0 enables DK40i customer data (configuration, station, and
system options) to be downloaded to a PC and stored on a computer disk. The customer data can
be added to, or changed, using the PC independent of the DK System.
The new customer data can then be uploaded to the DK System from the PC, changing customer
program options on-site or remotely over telephone lines and/or modems.
The DKBackup software program is also available. The program consists of a small subset of
DKAdmin functions which can perform backup, restore and upgrade functions, but cannot edit
customer databases.
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Strata DK40i
System Technology
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