Abstract: A docking adapter includes a male HDI 30 type connector (for connecting to a "POWERBOOK" portable computer) and a female DB 25 type connector (for connecting via a SCSI bus cable to either a "MACINTOSH" personal computer or a SCSI external hard drive). The pins of the HDI type connector are electrically connected to the corresponding pins of the DB type connector. The adapter includes a switch having an actuated position for grounding pin 1 of the HDI type connector to "dock" the portable computer in a disk operating mode facilitating data transfer with the "MACINTOSH" over the SCSI bus. When not in the actuated position, the portable computer may be connected to and access the external hard drive over the SCSI bus. The adapter also includes a light emitting diode (LED) connected between the termination power pins of the DB and HDI connectors and ground to monitor for the presence of termination power on the SCSI bus.

Abstract: A switchable active termination device internally mounted within a peripheral device and electrically connected to the end of a Small Computer Systems Interface (SCSI) bus cable. Through use of a pair of SCSI active terminator circuit chips, the termination device actively terminates the data lines of the bus cable in a first operating mode in response to a first digital command by providing precise resistive pull-up to a predetermined value on each data line. In a second mode of operation responsive to a second digital command, the termination device disconnects all terminating resistors. Activation of the termination modes is logically driven from an included switch, with visual indication of the presence of an active termination state provided by a light emitting diode.