摘要 |
A keyboard having keys activated by electrical contacts and the capacity to read one state from among four possible states, wherein the keyboard is a dipole disposed between two terminals between which are positioned in parallel three connectors, each including one of the electrical contacts, two of these connectors including diodes mounted anode to cathode, in such a way that the various states may be discriminated by means of the successive application of two reverse electrical voltages (V1, V2) to the terminals of the dipole and the corresponding detection of the logic states of the contacts using a logic detector. |