User's Guide

Operation consists of activating via the key switch. The device will initialize all of the sensors (including
GPS) and establish communications via cell in order to send a status report. If the cell in unavailable a
satellite message will be sent. This operation is repeated on a programmable interval. Between
reporting activities, the Versa unit places itself in a low power state to conserve battery life. If a sensor
that is monitored reports a change greater than a programmed threshold, a special report will be sent
immediately. Zigbee is processed by the EM357 as a parallel processor (coordinator). Zigbee will a
establish communications with its own wireless network with preselected nodes and synchronize timing
to allow both these nodes as well as the Versa Zigbee coordinator to enter a low power state between
reporting activities. Communication is selected to be Cell or Satellite but not both. Zigbee
communication is independent of the Cell and Satellite communication. GPS is active on an either a
periodic basis (to collect location information for a report) or on a continuous basis.
External sensors and power can be connected by wire using the external Versa connector. Details of the
connector interface are shown below. Available are a USB and a RS-232 interface as well as a
analog/digital port and several GPIO ports. Finally there is a regulated power (+3.3V) which is limited to
30 milliamps of current.
Versa is designed to be mounted a metalized surface using the attached magnets. For proper operation
of the satellite subsystem, the Versa unit must be mounted to allow the top surface to see the sky.
The reports generated by the Versa device are sent via either Cell or Satellite to a internet site which is
accessible by the user. This site is known as the Information Management Bureau (IMB).