A first communication device (200, 300) for transmitting and receiving regular data via a first predetermined regular bidirectional interface (201, 301), respectively, to and from a second communication counterpart device, and for transmitting and receiving additional data via a first predetermined additional bidirectional interface (221, 321), respectively, to and from the second communication counterpart device, wherein the first communication device (200, 300) has: a predetermined pinout comprising a predetermined regular pinout (202, 206; 302, 306), which corresponds to the predetermined regular bidirectional interface (201, 301) configured to support regular bidirectional communication of regular data with the second communication counterpart device, and a predetermined additional pinout (220, 320), which corresponds to the predetermined additional bidirectional interface (221, 321) configured to support additional bidirectional communication of additional data with the second communication counterpart device; wherein the additional pinout (220, 230) comprises at least a first additional pin (220, 230), wherein the corresponding additional bidirectional interface (221, 321) comprises a first input/output, I/O, cell (222, 322), which has a first input (222-1, 322-1) that is communicatively coupled to the first additional pin (220, 320) and a first output (222-2, 322-2), and which is configurable to operate either as a first additional output driver or as a first additional input cell; wherein the first communication device (200, 300) has a first additional default data handling circuitry, which is communicatively coupled to the first output (222-2, 322-2) of the first I/O cell (222, 322), and which is configured to transmit and receive additional default data via the additional bidirectional interface (221, 321), when a default mode is active; and wherein the first communication device (200, 300) further has a first additional function data handling circuitry (230, 330), which is communicatively coupled to the first output (222-2, 322-2) of the first I/O cell (222, 322), and which is configured to transmit and receive additional function data via the additional bidirectional interface (221, 321), when an additional function mode is active; the first communication device (200, 300) further having an additional pin monitoring device (224, 324), which is communicatively coupled to the first additional pin (220, 320), and which is configured to monitor data traffic via the first additional pin (220, 320) and to detect an additional function communication start signal present in the data traffic of additional default data received via the first additional pin (220, 320), and which is further configured to deactivate the default mode and to activate the additional function mode, when an additional function communication start signal is detected in the data traffic of additional default data received via the first additional pin (220, 320). a predetermined pinout comprising a predetermined regular pinout (202, 206; 302, 306), which corresponds to the predetermined regular bidirectional interface (201, 301) configured to support regular bidirectional communication of regular data with the second communication counterpart device, and a predetermined additional pinout (220, 320), which corresponds to the predetermined additional bidirectional interface (221, 321) configured to support additional bidirectional communication of additional data with the second communication counterpart device; wherein the additional pinout (220, 230) comprises at least a first additional pin (220, 230), wherein the corresponding additional bidirectional interface (221, 321) comprises a first input/output, I/O, cell (222, 322), which has a first input (222-1, 322-1) that is communicatively coupled to the first additional pin (220, 320) and a first output (222-2, 322-2), and which is configurable to operate either as a first additional output driver or as a first additional input cell; wherein the first communication device (200, 300) has a first additional default data handling circuitry, which is communicatively coupled to the first output (222-2, 322-2) of the first I/O cell (222, 322), and which is configured to transmit and receive additional default data via the additional bidirectional interface (221, 321), when a default mode is active; and wherein the first communication device (200, 300) further has a first additional function data handling circuitry (230, 330), which is communicatively coupled to the first output (222-2, 322-2) of the first I/O cell (222, 322), and which is configured to transmit and receive additional function data via the additional bidirectional interface (221, 321), when an additional function mode is active; the first communication device (200, 300) further having an additional pin monitoring device (224, 324), which is communicatively coupled to the first additional pin (220, 320), and which is configured to monitor data traffic via the first additional pin (220, 320) and to detect an additional function communication start signal present in the data traffic of additional default data received via the first additional pin (220, 320), and which is further configured to deactivate the default mode and to activate the additional function mode, when an additional function communication start signal is detected in the data traffic of additional default data received via the first additional pin (220, 320).