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4.2 Basic system operation
The Hand Terminals communicate with the Host computer via the Wireless
Remot e Access Platform(s) (WRAP). The system can include one or more Hand
Terminals and one or more WRAPs. A WRAP can be interfaced directly to the
Host Computer using an RS232 interface, or indirectly via different networks
(WLAN, GPRS etc.) with network cable or with third party adapters. The Hand
Terminals can send/receive data to/from the Host Computer.
The integrity of data transfers between the systems components are always
checked using the check sum method. Data transfers are always acknowledged,
which assures that possible data loss due to e.g. radio interference is always
detected. Detection of data loss generates a resending process.
The maximum number of Hand Terminals per WRAP depends on the make and
model of the WRAP. The number of WRAPs is limited by the Bluetooth standard,
but may also depend on the make and model of WRAPs.
4.3 General operation of the Hand Terminal
Nordic ID RF650 is a thin client terminal. It is used as a user interface to a
Software application in Host Computer. The terminal cannot be utilized without
an application and a host computer.
The initial screen of the Hand Terminal displays a prompt (user configurable
header text) and an input field. This field can be filled with data from the
keyboard or by activating the Laser Scanner for a reading of a bar code or by
activating the RFID reader for a reading of an RFID tag.
Any text sent by the Host Computer will clear the screen and show the text
received from the Host Computer. Any user input (from the keyboard or the Laser
Scanner) would clear the text received from the Host Computer and the initial
screen will be displayed again.
The user starts a transaction by using the Hand Terminal keyboard to make an
entry, or by scanning a barcode or an RFID tag. The Hand Terminal then sends
this data to the Host Computer (via the WRAP and a possible network) and waits
for a message from the Host. If the Hand Terminal does not receive a correct
message within the specified time-out period, it will generate a “HOST NOT
ANSWER” status message on the screen.
