Patent ID: 7493422

Claim:
A method of determining by a removable media handling device which is part of a self-service terminal when a loss in communication exists between the removable media handling device and a device driver, said communication being effected using universal serial bus (USB) protocol over a USB, said method comprising the steps of: (i) monitoring by the removable media handling device for the presence of a single ended zero condition on the USB; (ii) monitoring by the removable media handling device for the presence of a failed re-enumeration attempt of said device; and (iii) upon detection by the removable media handling device of a single ended zero condition or a failed re-enumeration attempt meeting predetermined criteria chosen to indicate that said device is experiencing an unrecoverable loss of USB communication, recognizing that an unrecoverable loss of USB communication has occurred and directing the removable media handling device by firmware to perform a predetermined action chosen as a response to loss of communication, said predetermined action including outputting any media held in the removable media handling device.