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8 THE PIU UTILITY APPLICATION
8.1 Configuring the PIU and SIM Card Connection
In order to configure a PIU, the unit must be placed into its configuration mode, with an active
SIM card installed (see section 12.3 for details). With the unit powered off, press and hold F4
and then press F1 for 3 seconds or more, then release F1 and then F4. The unit should power up
into its configuration mode as indicated by F4 staying on. The unit may now be plugged into the
host PC using the supplied USB cable.
On checking the Device Manager of the Host PC that the PIU is connected to, the PIU Device will
be listed under the Ports (COM & LPT) section along with its allocated COM port number –
COM3 in the example shown in Figure 8 below.
Figure 8 - Device Manager Screen
The HAYSYS PIU application can now be started and the ‘Scan for devices’ button pressed. The
application will respond by automatically identifying if the connected unit is a PIU or a Remote
Reference Unit (RRU).