As the touch panel only consists of discrete components additional circuitry
needs to be added in order to perform the previously described measurements.
The main part of this is the touch controller that acts as an interface
between the touch panel and the host system. The touch controller is usually
implemented via an integrated circuit dedicated to this function or by
a microcontroller. In this thesis the touch controller is implemented using a
microcontroller from Microchip (section 2.2). The touch controller needs to
possess two essential properties. The rst one is that it needs to be equipped
with several A/D converters (or one multiplexed) in order to convert the
analog signals from the touch panel. The second one is the ability to provide
a connection to the host system supplying it with the measured data. This
connection is often established through a RS-232 or USB connection (more
on this topic in section 2.3).