Abstract: A method of calibrating data slicer-latches in a receiver to remove offset errors in the slicer-latches. A known voltage is applied to all but one of the inputs of the slicer-latch. The remaining input receives an offset cancelation voltage from a DAC is stepped upward from a minimum voltage until the slicer-latch output transitions by incrementing a codeword to the DAC and the codeword that resulted the transition is saved. Then the offset cancelation voltage is swept downward in steps from a maximum voltage until the slicer-latch output transitions and the codeword that caused the transition is averaged with the stored codeword. The average of the codewords is applied to the DAC to generate the offset cancelation voltage used during normal operation of the receiver.

Abstract: A method of calibrating data slicer-latches in a receiver to remove offset errors in the slicer-latches. A known voltage is applied to all but one of the inputs of the slicer-latch. The remaining input receives an offset cancelation voltage from a DAC is stepped upward from a minimum voltage until the slicer-latch output transitions by incrementing a codeword to the DAC and the codeword that resulted the transition is saved. Then the offset cancelation voltage is swept downward in steps from a maximum voltage until the slicer-latch output transitions and the codeword that caused the transition is averaged with the stored codeword. The average of the codewords is applied to the DAC to generate the offset cancelation voltage used during normal operation of the receiver.

Abstract: An apparatus includes a first coding circuit, a second coding circuit, and a plurality of source series terminated driver slices. The first coding circuit may be configured to generate a plurality of digital filter control codes in response to a plurality of filter coefficients and a control signal. The control signal selects between a plurality of communication specifications. The second coding circuit may be configured to generate a plurality of driver slice control codes in response to the plurality of digital filter control codes. The plurality of source series terminated driver slices configured to generate an output signal according to a selected one of the plurality of communication specifications in response to the plurality of driver slice control codes, a main cursor signal, a pre-cursor signal, and a post cursor signal.

Abstract: An apparatus includes a first coding circuit, a second coding circuit, and a plurality of source series terminated driver slices. The first coding circuit may be configured to generate a plurality of digital filter control codes in response to a plurality of filter coefficients and a control signal. The control signal selects between a plurality of communication specifications. The second coding circuit may be configured to generate a plurality of driver slice control codes in response to the plurality of digital filter control codes. The plurality of source series terminated driver slices configured to generate an output signal according to a selected one of the plurality of communication specifications in response to the plurality of driver slice control codes, a main cursor signal, a pre-cursor signal, and a post cursor signal.

Abstract: Described embodiments provide a method of calibrating, by a calibration engine, a phase-locked loop (PLL) having one or more adjustable oscillators. The method includes entering a calibration mode of the PLL. The PLL is set to an initial state, thereby selecting one of the adjustable oscillators for calibration, an initial threshold window, and an initial tuning band of the selected adjustable oscillator. If the control signal of the selected adjustable oscillator is not within the initial threshold window, the calibration engine iteratively adjusts at least one of: (i) the selected tuning band of the selected adjustable oscillator, (ii) the selected adjustable oscillator, and (iii) the selected threshold window until the control signal of the selected adjustable oscillator is within the adjusted threshold window. If the control signal is within the threshold window, the one or more calibration settings of the PLL are stored and used to set the PLL operation.

Abstract: Described embodiments provide a method of calibrating, by a calibration engine, a phase-locked loop (PLL) having one or more adjustable oscillators. The method includes entering a calibration mode of the PLL. The PLL is set to an initial state, thereby selecting one of the adjustable oscillators for calibration, an initial threshold window, and an initial tuning band of the selected adjustable oscillator. If the control signal of the selected adjustable oscillator is not within the initial threshold window, the calibration engine iteratively adjusts at least one of: (i) the selected tuning band of the selected adjustable oscillator, (ii) the selected adjustable oscillator, and (iii) the selected threshold window until the control signal of the selected adjustable oscillator is within the adjusted threshold window. If the control signal is within the threshold window, the one or more calibration settings of the PLL are stored and used to set the PLL operation.

Abstract: A method for determining quantization numbers for each macro block in one video segment having a prescribed capacity is disclosed. The quantization numbers determine how much data will be preserved for that macro block. The method begins by determining a level of complexity for each macro block. Next, initial quantization numbers are chosen for the macro blocks by choosing the largest values possible without exceeding the prescribed capacity of the video segment. Final quantization numbers are selected based on respective ones of the initial quantization numbers proportioned according to the level of complexity for that macro block. The final quantization numbers may be increased or decreased so that the capacity of the video segment is maximized but not exceeded.

Abstract: A method for determining quantization numbers for each macro block in one video segment having a prescribed capacity is disclosed. The quantization numbers determine how much data will be preserved for that macro block. The method begins by determining a level of complexity for each macro block. Next, initial quantization numbers are chosen for the macro blocks by choosing the largest values possible without exceeding the prescribed capacity of the video segment. Final quantization numbers are selected based on respective ones of the initial quantization numbers proportioned according to the level of complexity for that macro block. The final quantization numbers may be increased or decreased so that the capacity of the video segment is maximized but not exceeded.

Abstract: A system and method for performing an inverse discrete cosine transform (IDCT) based on DCT data is disclosed. The system is IEEE compliant and transforms one block (8×8) of pixels in 64 cycles. The IDCT processor receives the DCT input, produces the matrix (QXTQ)P, or XQP, in IDCT Stage 1 and stores the result in transpose RAM. IDCT Stage 2 performs the transpose of the result of IDCT Stage 1 and multiplies the result by P, completing the IDCT process and producing the IDCT output. The system performs the matrix function QXtQ, where X represents the DCT data and Q is a predetermined diagonal matrix. The resultant value is adjusted by discarding selected bits, and the system then postmultiplies this with the elements of a predetermined P matrix, and discards selected bits. The system performs a conversion and storing function and performs a sign change to obtain QXtQP. This completes first stage processing, which is then passed to transpose RAM.

Abstract: An inverse quantizer is provided with a reduced bit-width. In one embodiment, the inverse quantizer receives quantized DCT coefficients in sign+magnitude form with 1+11 bits of resolution, and produces reconstructed DCT coefficients with 1+11 bits of resolution. Although this is less than the theoretical minimum bit-width required to represent the entire reconstructed DCT coefficient range [−2048, 2047] mandated by the MPEG standard, certain IDCT implementations will maintain IEEE compliance when the −2048 value is replaced with −2047. (An example of one such implementation is provided in a co-pending application.) This reduces the range to [−2047, 2047]. In one embodiment, the inverse quantizer includes a dead-zone expander, a quantization multiplier, a mismatch controller, and a bit-width reducer. The dead-zone expander receives quantized coefficients with 1+11 bits of resolution, doubles them, and then increases their magnitude by one.

Abstract: A system and method for decoding an MPEG video bitstream comprising several macroblocks of data is disclosed. The system comprises a macroblock core (MBCORE) which processes video bitstream data and computes discrete cosine transform data corresponding to the processed video bitstream, and a parser which parses the video bitstream macroblocks into multiple data blocks used in subsequent stages of decoding. The system further includes a transformation/motion compensation core (TMCCORE) which is divided into multiple stages. The TMCCORE includes an IDCT first stage, an intermediate memory (transpose RAM), and an IDCT second stage. The IDCT first stage passes data to memory and the IDCT second stage receives data from memory. The IDCT first stage has the ability to operate on a first data block while the second stage simultaneously operates on a second data block. The TMCCORE receives the discrete cosine transform data from the MBCORE and calculates and reconstructs a frame therefrom using motion compensation.

Abstract: A system and method for decoding an MPEG video bitstream comprises, comprising a macroblock core (MBCORE) which processes video bitstream data and computes discrete cosine transform data and a parser which parses the video bitstream macroblocks into multiple data blocks used in subsequent stages of decoding. fixed length data words comprising variable length objects using a novel rotating register arrangement. A multistage transformation/motion compensation core (TMCCORE) uses intermediate memory. The IDCT first stage has the ability to operate on a first data block while the second stage simultaneously operates on a second data block. The TMCCORE receives the discrete cosine transform data from the MBCORE and calculates and reconstructs a frame therefrom using motion compensation. The MBCORE can operate on data from a first macroblock while the TMCCORE simultaneously operates on data from a second macroblock.