3. Interface Application

3.1 Power supply

The USB type 2.0 labelled POWER is used for power IoT Bit. The voltage input should be 5v with a minimum of

2A current for the IoT Bit. If the Raspberry Pi is powered via the IoT Bit, the input current should be at least 2.5A.

3.2 Battery

The battery should be a Li-Po with 3.7v and a minimum of 2 MAh capacity. The input voltage shouldn’t be higher

than 4.2v. The battery charging circuit can be damaged if it exceeds this and will void your warranty.

3.3 USB (modem)

USB type 2.0 labelled MODEM is used to connect the modem, it transmits data through the cable to the

Raspberry Pi or a Windows system. This USB interface gives you access to a few different ports on the modem.

Figure 5 - Power USB

Figure 6 - Battery Port

Figure 7 - Modem USB

List of ports accessible via the USB:

Diagnostics port for output developing messages

NMEA port - outputs GPS information

AT command port - for sending and receiving AT commands

Modem port for PPP protocol

USB-Audio port - use to transmit Audio signals

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