A control device for a meter device, particularly a water meter device, includes a first data interface for a meter unit measuring a flow of a fluid of the meter device, a second data interface for a reading device communicating with the meter unit through the control device, and a supply interface receiving a combined clock and voltage supply signal for the control device. The control device can assume a read mode in which data at the first data interface can be transmitted by the control device to the second data interface upon receiving a clock and voltage supply signal having a read signal variation. The control device can additionally assume a write mode in which data at the second data interface can be transmitted to the first data interface upon receiving a clock and voltage supply signal with a write signal variation different from the read signal variation.