The "Master" board is the core of the system and its role is to communicate both with all the other boards that make up the system and with a computer via serial port or through a USB port (using a special interface). The board also contains a switching converter that can provide the required 5V power supply to the axis boards using a variable 12Vdc to 24Vdc power supply itself. This allows for the whole system to be used in battery-operated portable machines. Two inputs fot Pt100 temperature probes allow for the compensation of thermal expansion of both the machine and the object to be measured. The master board features a serial RS232 port and a Can-Bus port for receiving data from the axis boards. A multi-frequency output allows for the measurement of as many as 120 points per second.