Abstract: Access control and security alarm apparatus protects a building including a plurality of protection zones and an electrically locked door. The electrically locked door can be associated with any of the zones without re-wiring. Each zone can be operated to an autosecure condition wherein the zone, after being switched from a secure mode to an access mode to permit authorized entry, is automatically switched back to the secure mode without further action by the user. The apparatus can also be operated to a master reset mode wherein an alarm signal generated in response to activation of a sensor is immediately reset upon deactivation of the sensor to permit the system including each sensor to be conveniently tested by a single operator.