Abstract: A host adapter integrated circuit that contains data transfer modules has a serial port that uses a single serial port pin to communicate with a slave serial port input-output integrated circuit that interfaces to various resources that are included in a support circuit. The serial port forms a packet from each byte of information to be transferred from a module to the slave device by adding a start bit before the byte, followed by a parity bit at the end of the byte and followed by a stop bit. After transmitting the packet, the serial port waits for an acknowledge packet from the slave serial port input-output integrated circuit, for example for two clock cycles after transmission of the packet. For synchronous operation, a common oscillator drives the clock signal on the slave serial port input-output integrated circuit and host adapter integrated circuit.

Abstract: A host adapter integrated circuit that contains data transfer modules has a serial port that uses a single serial port pin to communicate with a slave serial port input-output integrated circuit that interfaces to various resources that are included in a support circuit. The serial port forms a packet from each byte of information to be transferred from a module to the slave device by adding a start bit before the byte, followed by a parity bit at the end of the byte and followed by a stop bit. After transmitting the packet, the serial port waits for an acknowledge packet from the slave serial port input-output integrated circuit, for example for two clock cycles after transmission of the packet. For synchronous operation, a common oscillator drives the clock signal on the slave serial port input-output integrated circuit and host adapter integrated circuit.

Abstract: A headerless hard disk architecture includes tracks that are grouped into logical zones and physical zones. The physical zones contains tracks which have similar data density and rotational velocity and therefore would have the same track format on a defect-free media. The logical zones are subdivisions of the physical zones and contain tracks similarly affected by defects on a media. A single track format for all of the tracks in a logical zone accounts for defects. A first data structure stored in a data buffer indicates boundaries of data sectors as defined by the track formats for the logical zones. A second data structure in the data buffer indicates which of the data sectors contain defects not accounted for by track formats. A disk controller uses a combination of information from the first and second data structures to identify logical data sectors requested for a data transfer.

Abstract: A hard disk controller integrated circuit of a SCSI target device comprises a dedicated command descriptor block "CDB" parsing state machine. The dedicated CDB parsing state machine parses incoming six-byte, ten-byte and twelve-byte SCSI command descriptor blocks and writes information from corresponding fields in the six-byte, ten-byte and twelve-byte SCSI command descriptor blocks into predetermined memory locations. In some embodiments, there are sixteen such predetermined memory locations which together comprise a 16.times.8 register file. A microprocessor coupled to the hard disk controller integrated circuit is therefore relieved of the burden of parsing incoming SCSI command descriptor blocks.

Abstract: A package system for populated circuit boards is disclosed. The circuit board is placed on a piece of conductive paperboard and is shrink wrapped with an antistatic film, which may be provided with a tearstrip. Placed on a cardboard carton, the package provides good protection against physical shocks, vibration and electrostatic discharge.