Abstract: A personal computer (PC) card insertion method and apparatus uses a subset of connector ground terminals and pins, located at either end of the connector, for detecting the onset of a card insertion. The host PC card slot connector has pull-up resistors for keeping the subset of ground terminals at a high logic level (V.sub.CC). Also, the subset of pins are made longer than the signal pins so that when an insertion of a PC card begins, the grounding of one or more of the subset of pins indicates that a PC card insertion has begun, allowing the host system to take the necessary precautions to ensure an orderly acceptance of the card without any undesirable system affects that might otherwise result. Also, a logic network for using the subset of connector terminals as additional grounding connections is provided upon completion of the insertion.

Abstract: A method applicable to a host computer system having a system bus connected to a CPU, and a PCMCIA controller having status registers, means for supplying back off signals to the CPU and line buffers capable of being in a normal and high impedance state. A multi pin connector is located in each card socket and connected to a line buffer. Each connector has common address, data and control pins, power pins, ground pins longer than the data pins and card detect signal pins shorter than the signal pins. The first step is to detect the commencement of an insertion or removal of a PCMCIA card to or from a socket by monitoring the ground and card detect signal pins. After detection, commence termination of all CPU usage of common address, data and control lines by asserting a back off signal. Next, determine if the usage is terminated by monitoring the status registers in the controller. Next, place the common address, data and control lines in a high impedance state.

Abstract: A write pulse generator circuit which uses first and second flip-flop circuits adapted to provide output pulses to an exclusive OR gate to generate write pulses. The circuit includes apparatus for toggling the first flip-flop in response to a rising edge of a clock pulse, and apparatus for toggling the second flip-flop in response to a falling edge of the clock pulse. By utilizing opposite phase output signals from the flip-flops, tuning of the circuit for particular operating conditions and for particular processes is eliminated.