Abstract: A method and apparatus for monitoring a data bus which transfers digital information and commands between components of a system wherein the bus operates according to a designated protocol and is of the serial, asynchronous type employing Manchester encoding. A bus interface provides communication with the bus for receiving and processing message data from the bus, and a storage interface provides communication with an external mass storage device such as a hard disk and also stores an operational program for the data bus recorder. A processor connected to both interfaces receives information from the storage interface which defines message collection via a configuration file, utilizes the operational program from the storage interface, controls operation of the bus interface including initialization and filtering of the bus message traffic in accordance with the configuration file, and controls transfer of recorded bus message data to the external mass storage device via the storage interface.