User Manual

“Halo” System: Communication Protocol 970-00002-000

EXI Wireless Systems, Confidential Page 8 of 33 July 27, 1999

3. System Architecture

The “Hallo’ system can be classified into the group of data gathering and control systems and its

components could be divided into 3 major groups:

• Host (Computer)

• Data gathering and control nodes (Controllers, Elevators, Receivers, Printer Interface, Programmers)

• Sensors (P-Tag, A-Tag, D-Tag)

Figure 1 shows how these units are organized within the system.

3.1. Host

The Host is Windows based User Interface running on a PC. It serves as a terminal from which the user can

monitor the system operation and exercise available controls. There can be only one Host and it is acting as

a Master device within the system. The Host must be equipped with the EIA-485 / EIA-232 converter in

order to be able to communicate to the rest of the system.

3.2. Data Gathering and Control Nodes

There are 3 types of the nodes in this group and they vary in their functionality, but one feature is common

among all of them; they are all able to communicate to the Tags and to the Host. These are two completely

different communication paths and will be examined in details in this document

Figure 1

Controller

Elevator

Host PC

RIM

Receiver

RIM

Receiver

Tag