Abstract: Aspects for generating CRT timing signals in a graphics accelerator are described. A method aspect includes shifting reference count values forward by a predetermined count period. A single comparator is utilized to perform a plurality of comparisons between CRT timing signals and at least one of the reference count values during the predetermined count period. Further, compensation for the shifting forward occurs by shifting back signals output from the single comparator. With the present invention, CRT timing signals are generated through time-shifting of relevant signals. The time-shifting further allows the utilization of a single comparator, which reduces the logic gate requirement and thus the area and cost.

Abstract: A method and system for concurrent processing of slices of a bitstream in a multiprocessor (MP) system is disclosed. The MP system includes a number of identical processors and a common memory. The memory is for receiving a plurality of bitstreams (preferably MPEG2 bitstreams) as a plurality of slices. The method and system comprises accessing a semaphore register by one of the plurality of processors and searching for an associated slice within the memory by the one processor. The method and system further comprises processing the associated slice by the one processor. Finally, the method and system comprises updating a memory location which holds the last address of the associated slice by the one processor; wherein subsequent processors search for each of the plurality of slices from the updated last address in the register. A system and method in accordance with the present invention provides for intercommunication between the plurality of processors within a multiprocessing system.

Abstract: A method and system for synchronizing a reference signal and an output signal produced by an electrical circuit, the electrical circuit comprising an analog portion and a digital portion, is disclosed. The method comprises the steps of utilizing the digital portion to produce a phase-adjusted signal and utilizing the analog portion to produce an output signal in substantially the same phase as the phase-adjusted signal. Through the use of the method and system in accordance with the present invention, the large bi-direction shift register of conventional hybrid DLLs is no longer necessary and high speed DLLs will be capable of providing high resolution deskewed clocks in a shorter amount of time. The use of the present invention also facilitates the coverage of a wider range of clock frequencies.

Abstract: Aspects for effectively improving the throughput in a rasterization pipeline for image rendering in a computer system are provided. A method aspect includes receiving data for a chosen number of pixels in a Z-test mechanism of the rasterization pipeline, performing Z-test determinations for the chosen number of pixels in a same clock cycle to achieve faster processing in the Z-test mechanism than other portions of the rasterization pipeline, and tagging the chosen number of pixels based upon the Z-test determinations to indicate pass/fail status for rendering.

Abstract: Aspects for increasing efficiency of memory accesses during graphics rendering are provided. A preferred method aspect includes providing a plurality of memory banks for data, and decoding input signals that indicate accessing of at least one of the plurality of memory banks for a desired plurality of words of data. The method further includes splitting data access across the plurality of memory banks to allow parallel selection of an output from at least one of the plurality of memory banks as the desired plurality of words of the data, wherein latency of data access is amortized.

Abstract: A method and structure for a refresh operation with a low voltage of logic high in a computer memory structure is provided. The method and system includes first the precharging of a plurality of bit lines and a plurality of complementary bit lines to a voltage higher than the reference voltage. Then at least one of a plurality of word lines and at least one of a plurality of reference word lines are selected. Next, the sense amplifier is activated such that either the plurality of bit lines or the plurality of complementary bit lines discharges to a voltage of logic low. This discharge creates a voltage difference between the plurality of bit lines and the plurality of complementary bit lines. The resulting voltage on the bit lines is restored to the memory cells on the selected word lines. Then, the plurality of bit lines and the plurality of complementary bit lines are restored to the reference voltage. This method and structure allows the use of a logic high voltage lower than 2.

Abstract: A digital delay lock loop (DLL) circuit for clock signals with reduced delay line length includes a first phase difference detector for detecting a first phase difference, and a second phase difference detector for detecting a second phase difference. The circuit further includes an inverter for inverting an input clock signal, and a switch controlled by the second phase difference detector for switching between the input clock signal and the inverted input clock signal in accordance with the second phase difference to provide a clock signal to the first phase difference detector. In a method aspect, a method for reducing delay line length in a digital delay locked loop (DLL) includes determining a phase difference between an input clock signal and a feedback clock signal, and maintaining the phase difference between the input clock signal and the feedback clock signal within approximately 180.degree..

Abstract: Method and circuit aspects for improving lock-in time following power-up in a phase-locked loop are provided. The circuit and method for providing same includes a phase-locked loop, the phase-locked loop comprising a low pass filter, and a pulse generation circuit coupled to the low pass filter. The pulse generation circuit provides a control pulse of predetermined duration to increase a voltage across the low pass filter and reduce lock-in time in the phase-locked loop following power-up. The pulse generation circuit further includes a plurality of logic gates, the plurality of logic gates including a plurality of inverters coupled to a NAND gate.

Abstract: Aspects for self bootstrapping word-line driver circuitry are provided. In a circuit aspect, a word-line driver circuit for a memory cell in a semiconductor memory includes a signal input means, the signal input means comprising a first plurality of transistors, the first plurality of transistors receiving an input voltage signal higher than a voltage supply signal of the semiconductor memory. The circuit further includes a signal output means, the signal output means comprising a second plurality of transistors coupled to the first plurality of transistors and providing an output drive signal sufficient for the memory cell.

Abstract: A memory is modified so that read and write data are transferred on both rising and falling edges of a timing signal, thereby essentially doubling the data transfer rate from memory. In one embodiment, a dual-edge extended data out (DE.sup.2 DO) memory includes modified and improved circuits and operating methods, as compared to a standard extended data out (EDO) memory, so that read and write data are transferred on both rising and falling edges of a timing signal. In a described embodiment, DE.sup.2 DO dynamic RAM (DRAM) reads and writes data on the rising and falling edges of a column address strobe (CAS) timing signal. By transferring data on both the rising and falling edges of the timing signal, the data transfer rate to and from the memory is effectively doubled.

Abstract: Circuit, method, and system aspects for achieving redundancy circuitry programming in semiconductor memory are provided. Through these aspects, utilization of a circuit including a logic mechanism for receiving an enable signal and an address signal, a switching mechanism coupled to the logic mechanism for controlling delivery of the address signal, and a fuse mechanism coupled to the logic mechanism for allowing selective address programming responsive to the address signal in order to produce a desired logic level for a redundant address output signal occurs to form an address programming circuit. Further, selective input of an enable signal to the address programming circuit provides control of the address programming circuit to produce a desired logic level output. Additionally, integration of a plurality of the address programming circuits to form a redundancy programming circuit is achieved with each address programming circuit corresponding to one bit of an input address signal.

Abstract: A system and method for automatically refreshing a dynamic random access memory is disclosed. The system comprises a timer, a trigger, and refresh generation means coupled to the timer and the trigger. The timer provides a first refresh rate. The first refresh rate is a required number of refreshes for a particular interval of time. The trigger provides a trigger signal. The trigger signal is a periodic signal. The refresh generation provide a plurality of refreshes at a second refresh rate in response to the trigger signal. The system functions such that the second refresh rate adapts to the first refresh rate.

Abstract: A system and method for a dynamic random access memory. The dynamic random access memory further comprises a memory block and a plurality of data lines. The memory block further comprises a plurality of memory cells. The plurality of memory cells are arranged into a plurality of rows and a plurality of columns. The plurality of data lines is proportional to the plurality of columns. Each of the plurality of data lines is substantially parallel to the plurality of columns.

Abstract: Apparatus, method, and system aspects for providing efficient accesses to memory in a computer system, the computer system including a controller, are described. Included in the aspects are a random access memory array having a plurality of rows and columns and coupled to the controller, and a column selection mechanism coupled to the memory array and the controller with the column selection mechanism being divided into predetermined portions for providing column selection signals to access chosen portions of a row in the memory array. Further included as the column selection mechanism is a multiplexer. In one embodiment, the multiplexer is divided into halves and provides separate selection signals for accessing upper word halves and lower word halves of the random access memory.