摘要:
Described are mathematical circuits that perform flexible rounding schemes. The circuits require few additional resources and can be adjusted dynamically to change the number of bits involved in the rounding. In one embodiment, a DSP circuit stores a rounding constant selected from the group of binary numbers 2(M−1) and 2(M−1)−1, calculates a correction factor, and sums the rounding constant, the correction factor, and a data item to obtain a rounded data item.
摘要:
Described is a programmable logic device (PLD) with columns of DSP slices that can be combined to create DSP circuits of varying size and complexity. DSP slices in accordance with some embodiments includes programmable operand input registers that can be configured to introduce different amounts of delay, from zero to two clock cycles, for example, to support pipelining. In one such embodiment, each DSP slice includes a partial-product generator having a multiplier port, a multiplicand port, and a product port. The multiplier and multiplicand ports connect to the operand input port via respective first and second operand input registers, each of which is capable of introducing from zero to two clock cycles of delay. In another embodiment, the output of at least one operand input register can connect to the input of an operand input register of a downstream DSP slice so that operands can be transferred among one or more slices.
摘要:
A clock gating circuit is provided for a logic device that reduces device resource requirements, eliminates the need for users to define their own clock gating circuit, and eliminates undesirable clock signal disturbances, such as glitches and runt pulses. In one embodiment, the clock gating circuit includes an input terminal for receiving an input clock signal; an input terminal for receiving a clock enable signal; a storage latch coupled to receive the input clock signal and the clock enable signal, and in response, provide a clock gate control signal; and a logic gate coupled to receive the input clock signal and the clock gate control signal. The logic gate selectively routes the input clock signal in response to the clock gate control signal, thereby providing an output clock signal.
摘要:
A digital signal processing block having: 1) a first digital signal processing element including: a first multiplexer of a first plurality of multiplexers, the first multiplexer selecting between a first data input and a first zero constant input; and a first arithmetic unit coupled to the first plurality of multiplexers, the first arithmetic logic unit configured for addition; and 2) a second digital signal processing element including: a second multiplexer of a second plurality of multiplexers, the second multiplexer selecting between a second data input and a second zero constant input; and a second arithmetic unit coupled to the second plurality of multiplexers and to a third multiplexer of the first plurality of multiplexers, the second arithmetic unit configured for addition.
摘要:
An integrated circuit for pattern detection including: an arithmetic logic unit coupled to a comparison circuit, where the arithmetic logic unit is programmed by an opcode; a selected pattern of a plurality of patterns selected by a first multiplexer, where the first multiplexer is coupled to the comparison circuit; and a register coupled to the comparison circuit for storing at least a partial comparison between an output of the arithmetic logic unit and the selected pattern.
摘要:
Described is a programmable logic device (PLD) with columns of DSP slices that can be cascaded to create DSP circuits of varying size and complexity. Each DSP slice includes a plurality of operand input ports and a slice output port, all of which are programmably connected to general routing and logic resources. The operand ports receive operands for processing, and a slice output port conveys processed results. Each slice additionally includes a feedback port connected to the respective slice output port, to support accumulate functions in this embodiment, and a cascade input port connected to the output port of an upstream slice to support cascading.
摘要:
Described is a programmable logic device (PLD) with columns of DSP slices that can be combined to create DSP circuits of varying size and complexity. DSP slices in accordance with some embodiments includes programmable operand input registers that can be configured to introduce different amounts of delay, from zero to two clock cycles, for example, to support pipelining. In one such embodiment, each DSP slice includes a partial-product generator having a multiplier port, a multiplicand port, and a product port. The multiplier and multiplicand ports connect to the operand input port via respective first and second operand input registers, each of which is capable of introducing from zero to two clock cycles of delay. In another embodiment, the output of at least one operand input register can connect to the input of an operand input register of a downstream DSP slice so that operands can be transferred among one or more slices.
摘要:
Structures and methods of including processor capabilities in an existing PLD architecture with minimal disruption to the existing general interconnect structure. In a PLD including a column of block RAM (BRAM) blocks, the BRAM blocks are modified to create specialized logic blocks including a RAM, a processor, and a dedicated interface coupled between the RAM, the processor, and the general interconnect structure of the PLD. The additional area is obtained by increasing the width of the column of BRAM blocks. Because the interconnect structure remains virtually unchanged, the interconnections between the specialized logic blocks and the adjacent tiles are already in place, and the modifications do not affect the PLD routing software. In some embodiments, the processor can be optionally disabled, becoming transparent to the user. Other embodiments provide methods of modifying a PLD to include the structures and provide the capabilities described above.
摘要:
An integrated circuit that includes a digital signal processing element (DSPE) having a first and a second register block coupled to a first arithmetic logic unit (ALU) circuit; a middle DSPE adjacent to the top DSPE having a third and a fourth register block coupled to a second ALU circuit, where the third register block is coupled to the first register block, and the fourth register block register block is coupled to the second register block; and a bottom DSPE adjacent to the middle DSPE having a fifth and a sixth register block coupled to a third ALU circuit, where the fifth register block is coupled to the third register block and the sixth register block register block is coupled to the fourth register block.
摘要:
An integrated circuit for pattern detection including: an arithmetic logic unit coupled to a comparison circuit, where the arithmetic logic unit is programmed by an opcode; a selected pattern of a plurality of patterns selected by a first multiplexer, where the first multiplexer is coupled to the comparison circuit; and a register coupled to the comparison circuit for storing at least a partial comparison between an output of the arithmetic logic unit and the selected pattern.