Access control reader with double technology: proximity and keypad, on the same board. Independent or joint operation for greater security. (1) Independent operation: (1.1) Proximity, which allows the door to be opened by approaching a proximity card or key fob. (1.2) Keypad, which allows the door to be opened by entering a previously programmed code of up to 6 digits. (2) Joint operation for greater security: card + PIN code. (2.1) Reader that allows the door to be opened by approaching a proximity card or keyfob + a 4-digit PIN code. (2.2) Proximity reader that by means of a dipswitches configuration (SW2) that it incorporates can work in an autonomous or centralized system. OPTION 1: Configuration as CENTRALIZED MDS-AC Plus. OPTION 2: Configuration as CENTRALIZED with Wiegand 26 protocol. Frequency: 125kHz.