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:
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:
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:
A fast linked multiprocessor network (22) including a plurality of processing modules (24, 26, 28, 30, 32, and 34) implemented on a field programmable gate array (10) and a plurality of configurable uni-directional links (21, 23, 25, 27, 29, 31) coupled among at least two of the plurality processing modules providing a streaming communication channel between at least two of the plurality of processing modules.
摘要:
A novel coprocessor interface providing memory access without traversing the main processor, and methods of operating the same. A system includes a bus, a processor circuit, a memory circuit, a multi-channel memory controller, and at least one coprocessor. The processor circuit is coupled to the bus, the multi-channel memory controller is coupled between the bus and the memory circuit, and the coprocessors are coupled to both the processor circuit and the multi-channel memory controller. This circuit arrangement provides dedicated high speed channels for data access between the coprocessors and the memory circuit, without traversing the processor circuit or the bus. Thus, non-standard (e.g., non-sequential) data transfer protocols can be supported. In some embodiments, the system is implemented in a programmable logic device (PLD). The processor circuit can be, for example, a microprocessor included as hard-coded logic in the PLD, or can be implemented using programmable logic elements of the PLD.
摘要:
Within a system comprising a programmable integrated circuit (IC), a method can include storing a first configuration within the system in a read-only memory that is independent of the programmable IC. The programmable IC, being loaded with the first configuration, comprises a circuit that accesses a data source external to the system over a communication link. A second configuration can be downloaded by the programmable IC from the data source. The second configuration can be stored within a random access memory within the system that is independent of the programmable IC. Responsive to a reconfiguration event, the programmable IC can be loaded with the second configuration from the random access memory.
摘要:
A configurable logic element (CLE) for a field programmable gate array (FPGA) includes “expanders”, i.e., connectors that allow fast signal communication between logic blocks. Expanders allow the configurable interconnection of a plurality of logic blocks, or portions thereof, to form a single logical entity that can implement large user circuits such as PALs, lookup tables, multiplexers, tristate buffers, and memories. One embodiment includes a configurable logic block. In a first mode, the logic block provides two N-input LUTs having N shared inputs and two separate outputs. The outputs are then combined using an expander to generate an (N+1)-input function. In a second mode, the logic block provides two N-input LUTs having M unshared inputs. An optional third mode provides a plurality of product term output signals based on the values of the N input signals.
摘要:
A logic/memory circuit (LMC) utilized in a configurable logic block (CLB) of a programmable logic device (PLD) that implements an eight-input lookup table (LUT) using an array of programmable elements arranged in rows and columns. A decoder is used to read bit values from one column (e.g., sixteen programmable elements) of the array. In one embodiment, a separate read bit line is provided to facilitate faster read operations. A sixteen-to-one multiplexer/demultiplexer circuit is used to pass selected bit values to an output terminal. The array of programmable elements is programmable both from configuration lines during a configuration mode, and by data transmitted on the interconnect resources through the multiplexer/demultiplexer circuit. In one embodiment, the programmable elements of the array are connected in pairs to product term generation circuitry, and input signals to the array are routed onto bit lines that are also connected to the product term generation circuitry. Product terms generated by the product term circuitry are passed to a macrocell circuit to perform programmable array logic (PAL) logic operations.
摘要:
A logic/memory circuit (LMC) utilized in a configurable logic block (CLB) of a programmable logic device (PLD) that implements an eight-input lookup table (LUT) using an array of programmable elements arranged in rows and columns. A decoder is used to read bit values from one column (e.g., sixteen programmable elements) of the array. In one embodiment, a separate read bit line is provided to facilitate faster read operations. A sixteen-to-one multiplexer/demultiplexer circuit is used to pass selected bit values to an output terminal. The array of programmable elements is programmable both from configuration lines during a configuration mode, and by data transmitted on the interconnect resources through the multiplexer/demultiplexer circuit. In one embodiment, the programmable elements of the array are connected in pairs to product term generation circuitry. Product terms generated by the product term circuitry are passed to a macrocell circuit to perform programmable array logic (PAL) logic operations. In another embodiment, a CLB includes four LMCs and a multiplier circuit such that large amounts of logic are locally implemented, thereby avoiding signal delays associated with transmission over general purpose interconnect resources within a PLD.
摘要:
Circuits and methods for a differential signal interface for coupling differential signals at a first frequency on a pair of opposite polarity signals to a multiple gigabit transceiver with generic buffers for receiving, transmitting or transceiving out of band signals at a second frequency lower than the first frequency are disclosed. Termination networks are provided coupling generic input buffers to respective ones of the pair of opposite polarity signals for receiving out of band signals where the opposite polarity signals are placed at voltages so that the differential voltage between them is below a threshold voltage. Methods for providing generic buffers with multiple gigabit transceivers for receiving and transmitting out of band signals on a differential signal interface are provided. Out of band signals are received when the out of band signaling protocol is not known.