摘要:
Field programmable gate arrays (FPGA's) may be structured in accordance with the disclosure to have a register-intensive architecture that provides, for each of plural function-spawning LookUp Tables (e.g. a 4-input, base LUT's) within a logic block, a plurality of in-block accessible registers. A register-feeding multiplexer means may be provided for allowing each of the plural registers to equivalently capture and store a result signal output by the corresponding, base LUT of the plural registers. Registerable, primary and secondary feedthroughs may be provided for each base LUT so that locally-acquired input signals of the LUT may be fed-through to the corresponding, in-block registers for register-recovery purposes without fully consuming (wasting) the lookup resources of the associated, base LUT. A multi-stage, input switch matrix (ISM) may be further provided for acquiring and routing input signals from adjacent, block-interconnect lines (AIL's) and/or block-intra-connect lines (e.g., FB's) to the base LUT's and/or their respective, registerable feedthroughs. Techniques are disclosed for utilizing the many in-block registers and/or the registerable feedthroughs and/or the multi-stage ISM's for efficiently implementing various circuit designs by appropriately configuring such register-intensive FPGA's.
摘要:
A field-programmable gate array device (FPGA) having plural rows and columns of logic function units (VGB's) further includes a plurality of embedded memory blocks, where each memory block is embedded in a corresponding row of logic function units. Each embedded memory block has an address port for capturing received address signals and a controls port for capturing supplied control signals. Interconnect resources are provided including a Memory Controls-conveying Interconnect Channel (MCIC) for conveying shared address and control signals to plural ones of the memory blocks on a broadcast or narrowcast basis.
摘要:
A Variable Grain Architecture (VGA) is used for synthesizing from primitive building elements (CBE's) an appropriate amount of dynamic multiplexing capability for each given task. Unused ones of such Configurable Building Elements (CBE's) are reconfigured to carry out further logic functions in place of the dynamic multiplexing functions. Each CBE may be programmably configured to provide no more than a 2-to-1 dynamic multiplexer (2:1 DyMUX). The dynamically-selectable output of such a synthesized 2:1 DyMUX may then be output onto a shared interconnect line. Pairs of CBE's may be synthetically combined to efficiently define 4:1 DyMUX's with each such 4:1 multiplexer occupying a Configurable Building Block (CBB) structure. Pairs of CBB's may be synthetically combined to efficiently define 8:1 DyMUX's with each such synthesized 8:1 multiplexer occupying a vertically or horizontally-extending leg portion of an L-shaped, VGB structure (Variable Grain Block). The so-configured leg portion of the VGB may then output the signal selected by its 8:1 DyMUX onto a shared interconnect line that is drivable by the VGB leg. Pairs or quartets of VGB's may be synthetically combined to efficiently define higher order, N:1 DyMUX's.
摘要:
A serial scan chain extends into an array of SRAM cells within a multi-ported memory system for allowing serial introduction of write data into the SRAM cells and serial read-back of the data. Initial data may be pre-loaded into the SRAM cells by way of the serial scan chain before being read parallel-wise in response to read requests submitted through any of multiple, parallel data access ports of the system.
摘要:
A Variable Grain Architecture is disclosed wherein Variable Grain Blocks (VGB's) are wedged together in mirror opposition to one another to define super-VGB structures. The super-VGB structures are arranged as a matrix within an FPGA device. Each VGB includes progressive function synthesizing layers for forming more complex function signals by folding together less complex function signals of preceding layers. A function spawning layer containing a set of function spawning lookup tables (LUT's) is provided near the periphery of the corresponding super-VGB structure. In one case, the function spawning layer is L-shaped and includes a symmetrical distribution of Configurable Building Blocks. A signal-acquiring layer interfaces with adjacent interconnect lines to acquire input terms for the LUT's and controls. A decoding layer is interposed between the signal-acquiring layer and the function spawning layer for providing strapping and intercept functions. Each VGB has a common controls section, a wide-gating section and a carry-propagating section. Each super-VGB has a centrally-shared section of longline drivers that may be accessed from any of the constituent VGB's. A diversified spectrum of interconnect lines, including 2xL, 4xL, 8xL and direct connect surround each super-VGB to provide different kinds of interconnect.
摘要:
A hierarchical switch matrix in a very high-density programmable logic device (CPLD) interconnects a multiplicity of programmable logic blocks in the CPLD. A new level of functionality coupled with high speed is provided by the hierarchical switch matrix. The hierarchical switch matrix includes three levels, a global switch matrix, a segment switch matrix and a block switch matrix. The block switch matrix provides a high speed signal path for signals within a programmable logic block. The segment switch matrix provides a high speed means of communication for signals within a segment, while the global switch matrix provides a high speed path for communication between segments. The hierarchical switch matrix of this invention provides a fixed, path independent, uniform, predictable and deterministic time delay for each group of signals routed through the hierarchical switch matrix.
摘要:
A programmable optimized-distribution logic allocator enhances the speed, silicon utilization, logic efficiency, logic utilization, and scalability of very high-density CPLDs including the logic allocator. The programmable optimized-distribution logic allocator provides an optimized number of product terms to each I/O pin of the CPLDS and the same uniform number of product terms as feedback. However, no product terms are permanently connected to either a particular macrocell or a particular I/O pin. The programmable optimized-distribution logic allocator includes a multiplicity of router elements where each router element steers a sum of a selected number of sum-of-product terms from a PAL structure, i.e, a selected number of logic product-term clusters, to a programmably selected logic macrocell. Specifically, the programmable optimized-distribution logic allocator has a plurality of input lines, a plurality of output lines and a plurality of programmable router elements. Each programmable router element has an input terminal connected an input line in the plurality of input lines and an output terminal connected to an output line in the plurality of output lines.
摘要:
A Variable Grain Architecture (VGA) device includes a shared output component (SOC) that may be used for programmably-routing process result signals onto either or plural ones of differently directed longlines within an FPGA. Plural VGB's make shared use of each SOC to output respective function signals to the longlines. The SOC may be also used for programmably-routing signals (e.g., feedthrough signals) that are selectively acquired from either one of equivalent but differently positioned interconnect channels. Such freedom in routing VGB result signals or feedthrough signals can allow FPGA configuring software to explore a wider range of partitioning, placement and/or routing options for finding optimized implementations in the VGA FPGA device of various, supplied design specifications.
摘要:
A logic array device has an array of plural interconnect resources including plural lines and plural switchbox areas, with an array of plural Variable Grain Blocks (VGB's) interspersed within the array of plural interconnect resources. The array of plural interconnect resources does not regularly include lines of single-length or shorter, and the array of plural interconnect resources does not regularly include switchbox areas that are spaced apart from one another by distances of a single-length or shorter. The single-length corresponds to a traverse of a continuous distance covering approximately one VGB.
摘要:
A tileable structure is provided for logic array devices. The tileable structure has a mirror-symmetrical arrangement of sets of logic blocks, common control sections for the logic block sets, surrounding interconnect lines, and switching areas at intersections of the interconnect lines.