Abstract: A multimedia system including an audio/video decoder/decompresser for decoding/decompressing a compressed encoded audio/video data stream to generate video images for display and audio signals for audible reproduction. The multimedia system includes an integrated system and video decoder with an audio/video synchronization circuit for substantially synchronizing the display of video images with audio playback. In addition, a step control is provided to allow for viewing of video images on a frame-by frame basis or to freeze or play video in slow motion. When step control is activated, audio output is muted. Audio data corresponding to displayed video is transmitted to the muted audio decoder. An internal system clock may be suppressed to the system clock counter. An external CPU may provide system clock start times corresponding to video frames to be displayed. The external CPU may increment the system clock counter by a an amount corresponding to the difference between a successive frame or number of frames.

Abstract: An apparatus for providing register compatibility between integrated circuits having different register and interrupt configurations is designed to operate with software that was written for previous hardware. Versions of software written for previous hardware attempt non-native register accesses for which the integrated circuit is designed to emulate the non-native register set. Versions of software specifically written for the present hardware attempt native register accesses for which no emulation is necessary. In the preferred embodiment only one physical register set is included on the integrated circuit and a compatibility engine is used when a non-native register access is attempted. The compatibility engine is coupled between a bus interface unit and the physical register set and allows a user or system designer to address a register set of another integrated circuit having a different configuration than the physical register set.

Abstract: A peripheral interface system and apparatus including a pair of integrated circuits, referred to as a system adapter and a socket controller, use a communication protocol, referred to as a windowed-interchip-communication protocol, to interface peripherals, such as PCMCIA cards or infrared devices, and other subsystems having different formats with a CPU system bus. The system adapter communicates to a hard disk drive subsystem using the ATA communication standards to interface an ATA hard disk drive with the CPU system bus. Communication between the system adapter and the socket controller, which communicates with PCMCIA peripheral cards and IR peripherals, is accomplished using the windowed-interchip-communication protocol which may share hardware resources with other communication protocols. Communication between the system adapter and the hard disk drive and between the system adapter and the socket controller may be provided on the same chain of a standard 40 signal ribbon cable.