Abstract: A control module (12) for a battery-powered data gathering apparatus (10) in which a microcontroller (18) selectively activates and deactivates components in the apparatus in a power saving manner. By controlling power consumption, the control module may maximise the working lifetime of the cell (14) (e.g. battery) which provides power. In one aspect, the microcontroller is operable as a host controller for a USB cellular modem, whereby the control module enables a conventional cell to power periodic communications from a USB cellular modem. The microcontroller activates the USB interface only when it is required, thereby closely controlling power consumed by the USB interface and its corresponding connected device.