Abstract: The present invention is an on board internal peripheral component interconnect (PCI) bus tester for testing internal components of a microelectronic chip. The present invention includes internal PCI testing agents that facilitate the application of test vectors to internal PCI agents from a minimal number of external periphery pins on the chip. The on board internal peripheral component interconnect (PCI) bus tester then captures the state of an internal PCI bus and transmits it though the external periphery pins of the chip for analysis to determine if the internal agent components are functioning correctly.

Abstract: A method for optimizing the performance of a 64-bit PCI initiator when transferring a 64-bit data via a 64-bit PCI bus. The 64-bit PCI initiator receives a single 64-bit data for transfer via the 64-bit PCI bus. The 64-bit PCI initiator breaks the 64-bit data into a first 32-bit data and a second 32-bit data. The 64-bit initiator then initiates a data transaction with the target device arbitrating for ownership of the 64-bit PCI bus. Upon receiving ownership of the 64-bit PCI bus, the 64-bit PCI initiator transfers the first 32-bit data and then transfers the second 32-bit data to the target device via the 64-bit PCI bus. The first 32-bit data and the second 32-bit data are transferred by the 64-bit PCI initiator to the target device without the assertion of a REQ64# signal, such that a REQ64# ACK64# protocol is avoided, enabling a more efficient completion of the data transaction.

Abstract: A system and method that prevents address aliasing and eliminates the unnecessary clock cycle consumed by the use of a dual address cycle when using a single address cycle to transmit a target address in a computer system including target devices having addresses of different sizes, such as 32-bit and 64-bit target devices, with 32-bit and 64-bit addresses, respectively. In addition, a combination of single address cycles and dual address cycles may be used to prevent address aliasing while permitting access to the entire address spaces of the target devices. The computer system includes a bus, an initiator device coupled to the bus, a first target device coupled to the bus, and a second target device coupled to the bus. The first target device has a first address range containing a plurality of bits, and the second target device has a second address range containing a fewer number of bits than the first address range.

Abstract: A system and method for completing a read transaction between an initiator device and a host memory device in a computer system, in which the present invention optimizes the retry behavior of the initiator device and a target device. The system of the present invention includes a bus bridge device, wherein the bus bridge device includes a target device coupled to the initiator device via a bus; the host memory device coupled to the bus bridge device; and a timer mechanism coupled to the target device. The initiator device is adapted to initiate a present read transaction via the target device, such that an access is asserted between the initiator device and the target device. The timer mechanism is adapted to measure target latency for one or more read transactions preceding the present read transaction, and the timer mechanism is further adapted to use the target latency to calculate a dynamic target latency period.

Abstract: A system and method for eliminating unnecessary data transfers (e.g., null data phase transfers) in a computer system. The computer system comprises a bus, a target device coupled to the bus, and an initiator device coupled to the bus. The initiator device is adapted to transfer a data byte and a signal corresponding to the data byte over the bus to the target device, wherein the signal is equal to a first value to indicate that the target device is to accept the data byte and the signal is equal to a second value to indicate that the target device is to disregard the data byte. The initiator device is further adapted to decode the signal for each of a plurality of data bytes. The initiator device withholds transferring a subset of the data bytes to the target device when the signal corresponding to each of the data bytes in the subset is equal to the second value, thereby eliminating unnecessary data transfers.

Abstract: A system and method for using single address cycles and eliminating dual address cycles to transmit a target address in a computer system. The computer system comprises a bus, a central processing unit coupled to the bus, an initiator device coupled to the bus, and a target device coupled to the bus. The target device comprises a first configuration register which is adapted to use a configuration bit to indicate an address range of the target device. The central processing unit interrogates the first configuration register and communicates the address range indicated by the configuration bit to the initiator device. The initiator device comprises a second configuration register which is adapted to use a configuration bit to register the address range of the target device.

Abstract: A method and system that enables real-time peripheral devices to be connected to a computer system utilizing Universal Serial Bus architecture. The present invention empowers the computer system to perform an accurate determination of the moment in time a predetermined event occurred within a real-time peripheral device by utilizing the start of frame pulse transmitted from a USB host controller to peripheral devices connected to it. When a predetermined event occurs within a peripheral device, a first timer within the peripheral device starts incrementing to determine the amount of time that elapses until the next start of frame occurs. Once the next start of frame occurs, the first timer stops incrementing and stores the time before start of frame value. Every start of frame pulse causes a second timer located within the USB host controller to start incrementing.

Abstract: A system and method for preventing address aliasing when using a single address cycle to transmit a target address in a computer system that includes target devices having addresses of different ranges. The computer system comprises a bus, an initiator device coupled to the bus, a first target device coupled to the bus, and a second target device coupled to the bus. The first target device has a first address range comprising a plurality of bits, and the second target device has a second address range comprising a fewer number of bits than the first address range. The initiator device transmits a signal indicating the size of the target address and also separately transmits in a single address cycle the target address. The second target device disables its address decode logic in response to the signal from the initiator device provided that the size of the target address is greater than the second address range.

Abstract: The present invention comprises a multiple bus master PCI (peripheral component interconnect) bus system within an integrated circuit. The system of the present includes an integrated circuit fabricated onto a single semiconductor die. An internal PCI bus is built into the integrated circuit. The internal PCI bus is adapted to transmit and convey data signals. A plurality of PCI agents are built into the integrated circuit. Each of the plurality of PCI agents are designed to perform a respective function and each of the plurality of PCI agents are coupled to the internal PCI bus to transmit and receive data. The internal PCI bus and the plurality of PCI agents are built into the integrated circuit on the single semiconductor die to create a high performance device.

Abstract: A method and apparatus for optimizing sample fetching in a peripheral component interconnect (PCI) environment. In one embodiment the present invention generates a first sample page base address corresponding to a first part of a first address received from a digital signal processor (DSP). The present invention also generates a second sample page base address corresponding to a first part of a second address received from the DSP. The first and second generated sample page base addresses are then stored in respective first and second locations within a multiple entry sample page base address cache which can be accessed by the DSP without accessing a PCI bus. The first part of the first address is compared to a first part of a third address.

Abstract: The present invention comprises a cache based scan matrix keyboard controller system. The cache based scan matrix keyboard controller system includes a plurality of keys on a keyboard adapted to signal when a key is activated. The cache based scan matrix keyboard controller system also includes a cache memory component and a state machine. The cache memory component stores information regarding the keys for a period of time. The state machine is adapted to interpret the information in the cache memory component to efficiently control said keyboard in a manner that minimizes reliance on CPU processing and reduces expenditure of design, manufacturing and operating resources.

Abstract: A virtual contiguous system for combining multiple and arbitrarily-sized and aligned digital data packets from a PCI bus to a DSP circuit is disclosed. Information from the PCI bus is supplied directly to a plurality of FIFO RAM memory units. Each packet of digital data includes data packet descriptors identifying at least the start address for each data packet and the size of each data packet. The system utilizes this information to operate a read pointer and a write pointer to remove data from the FIFO RAM memory units on a sequential bit-by-bit basis and to supply said data packets to said RAM memory units by means of a write pointer operated by said control circuit. The information transfer is managed on the read side of the FIFO RAM memory units with minimal processing on the write side.

Abstract: A method and system that enables real-time peripheral devices to be connected to a computer system utilizing Universal Serial Bus architecture. The present invention empowers the computer system to perform an accurate determination of the moment in time a predetermined event occurred within a real-time peripheral device by utilizing the start of frame pulse transmitted from a USB host controller to peripheral devices connected to it. When a predetermined event occurs within a peripheral device, a first timer within the peripheral device starts incrementing to determine the amount of time that elapses until the next start of frame occurs. Once the next start of frame occurs, the first timer stops incrementing and stores the time before start of frame value. Every start of frame pulse causes a second timer located within the USB host controller to start incrementing.

Abstract: A method and system of detecting objects displayed on a display screen is described. Each object displayed on the screen visually emits a unique identification signal. The identification signal or lack of an identification signal is detected by a detector such as a light pen or video gun and the detector transmits the identification signal on a serial bus to the display screen graphics controller thereby indicating to the controller the position on the screen at which the detector is pointed.

Abstract: A method and system for detecting objects displayed on a display screen is described. Each object displayed on the screen visually emits a unique identification signal in the form of a color signal having multiple color components. The relative peak amplitude of each color component in the color signal is detected by sampling the color signal with photo-sensors corresponding to each color component. The sampled color components are digitized and transmitted to the display screen graphics controller thereby indicating to the controller the object on the screen at which the detector is pointed.

Abstract: A method and apparatus for optimizing sample fetching in a peripheral component interconnect (PCI) environment. In one embodiment the present invention generates a sample page base address corresponding to a first part of a first address received from a digital signal processor (DSP). The generated sample page base address is then stored in a sample page base address cache which can be accessed by the DSP without accessing a PCI bus. The first part of the first address is compared to a first part of a second address. Provided that the first part of the first address and the first part of the second address are the same, the present invention combines a second portion of the second address sent from the DSP with the generated sample page base address stored in the sample page base address cache. In so doing, the present invention generates a complete address of a sample to be fetched without accessing the PCI bus.

Abstract: An endian domain conversion circuit for converting data packets transmitted between two bus interfaces. The novel system advantageously eliminates any requirement for a large bit switch within the circuit's write data path. Instead, endian conversion intelligence is placed into the read data path. Double words (dwords) are individually received from an incoming data packet and bytes are parallel stored into the same byte location of several different first-in-first-out (FIFO) memories. In one example, the dwords are 32-bits each and the number FIFO memories used is four. An entire input data packet is received in this manner, incrementing the write address of the FIFO memories for each dword. Depending on the type of endian domain conversion required, if at all, endian conversion control circuitry of the present invention controls the manner in which the four exemplary FIFO memories are read (via a read pointer) and the manner which their data is supplied over the output bus to generate the output data.

Abstract: The system of the present invention comprises a system for implementing a real time capability in peripheral devices. The system of the present invention functions with a computer system including a processor, a memory, and a video controller, each coupled to a system bus. A USB (universal serial bus) controller is also coupled to the system bus for interfacing peripheral devices on a USB cable to the computer system. A first and second register are included in the USB controller for storing a controller frame number and a controller frame remaining, and a second and third register are included in the peripheral device for storing a device frame number and a device frame remaining. The peripheral device is coupled to the USB controller via a USB cable. A screen reference register is coupled to receive the controller frame number and the controller frame remaining from the USB controller and is coupled to receive a reference signal from a video controller.

Abstract: The present invention allows the behavior of a state machine to be readily modified by software after it has been fabricated in silicon. To perform these modifications, the present invention uses special patch registers, multiplexers, and comparators to bypass certain states within the sequence of states within the combinatorial logic of the state machine and/or add new state sequences. Each patch register stores a state to be patched, a next state, and outputs. The state to be patched is the state that will be modified, while the next state is the state the state machine transitions into from the state to be patched, and the outputs are the outputs generated and asserted by the state machine while within the next state. Many such patch registers can be used by the present invention to define many modifications. Using this patch mechanism, the present invention allows new states to be added and existing states to be removed from the sequence of states that the state machine cycles through.

Abstract: A predictive arbitration system for interfacing a plurality of peripheral component interconnect (PCI) agents coupled to a first PCI bus with a second PCI bus. In one embodiment, the present predictive arbitration system includes a first PCI bus adapted to transmit data signals. A plurality of PCI agents are coupled to the first PCI bus. A predictive arbiter is coupled to both the first PCI bus and a second PCI bus. The predictive arbiter is also coupled to the plurality of PCI agents. The predictive arbiter is configured to receive requests for access to the first or second PCI bus from any of the plurality of PCI agents. The predictive arbiter, upon receiving requests for access, transmits one of the requests to a second arbiter coupled to the second PCI bus, wherein the selected and transmitted request originates from a selected one of the plurality of PCI agents. The predictive arbiter is also adapted to receive a grant signal from the second arbiter in response to the selected and transmitted request.