Mentor Graphics Corporation

Meta System S.p.a.

M2000 Sa.

Jean Barbier

Frederic Reblewski

Olivier Lepape

Philippe Piquet

Carl Ebeling

Olvier V Lepape

Olivier Lepaps

Francois Douezy

Embodiments of the present disclosure provide methods and integrate circuits with dynamic phase alignment between an input data signal and a clock signal. In some embodiments, a sampling window of the input data signal may be determined and timing of the input data signal may be adjusted to enable the input data signal to be sampled within the sampling window. Other embodiments may be disclosed and claimed.

Dynamic phase alignment

Memory employing a plurality of five-transistor memory bit cells in a memory matrix and a power supply control circuit that is configured to provide a simultaneous full clear to all of the memory bit cells is described herein.

Memory with five-transistor bit cells and associated control circuit

Embodiments provide input/output devices having programmable logic that is programmable to operate input/output devices in one of two drive modes. In various embodiments, to operate an input/output device in a first drive mode, logic circuitry is programmable to couple a reference voltage to a gate of a transistor element of an output driver. In various embodiments, to operate an input/output device in a second drive mode, the logic circuitry is programmable to couple a bias voltage to the gate of the transistor element of the output driver. In various embodiments, the logic circuitry may also be programmable to couple one of a plurality of data inputs to the output driver to operate an input/output device in either a single-ended mode or a differential mode.

Merged programmable output driver

Embodiments of crossbar devices constructed with Micro-Electro-Mechanical Systems (MEMS) switches are disclosed herein. A crossbar device may comprise m input terminals, n output terminals, n control lines and m&#xd7;n MEMS switches coupled to the n control lines to selectively couple the m input terminals to the n output terminal. Each of the MEMS switches may comprise a contact node coupled to one of the m input terminals, a cantilever coupled to one of the n output terminals, a control node coupled to one of the n control lines to electrostatically control the cantilever to contact the contact node or be away from the contact node using electrostatic attractive or repulsive force respectively. The cantilever and the contact node are configured to remain in contact by molecular adhesion force, after the cantilever has been electrostatically controlled to contact the contact node, and the electrostatic attractive force has been removed. Other embodiments may be described and claimed.

Crossbar device constructed with MEMS switches

A regionally time multiplexed emulation system includes an emulator for emulating a circuit design. The emulator includes a plurality of reconfigurable logic devices with buffered I/O pins and reconfigurable logic elements. The reconfigurable logic devices are reconfigurable to emulate a circuit design using at least one user clock to clock the logic elements and at least one signal routing clock to time multiplex the routing of emulation signals between the reconfigurable logic devices, with the at least one signal routing clock being independent of the at least one user clock.

Regionally time multiplexed emulation system

A method and apparatus for clock generation and distribution in an emulation system is described. The present invention provides a method and apparatus for generating a derived clock signal with a circuit having a look up table. A counter circuit counts clock cycles and provides an index into the look up table. A frequency divider circuit may be used between the counter circuit and a base clock signal to provide an intermediate clock signal with a frequency that is less than the frequency of the base clock signal. In one embodiment, a selection circuit is provided to select between the base clock signal and an external clock signal.

Clock generation and distribution in an emulation system

A number of enhanced logic elements (LEs) are provided to form a FPGA. Each enhanced LE comprises a multiple input-single output truth table, and a complementary pair of master-slave latches having a data, a set and a reset input. Each enhanced LE further comprises a plurality of multiplexers and buffers, and control logic. Additionally, the improved FPGA further comprises a network of crossbars, a context bus, a scan register, and a plurality of trigger circuitry. As a result, each LE may be individually initialized, its signal state frozen momentarily, the frozen state be read, trace data be output, and trigger inputs be conditionally generated. Furthermore, the enhanced LEs may be used for 'level sensitive' as well as 'edge sensitive' circuit design emulations.

Field programmable gate array with integrated debugging facilities

A method and apparatus for tracing any node in an emulator, including hidden nodes of a circuit design, includes maintaining a correspondence between physically observable nodes and hidden nodes of the circuit design being emulated. The correspondence identifies how values of the hidden nodes are to be determined based on corresponding ones of the physically observable nodes. The value of a hidden node is determined by obtaining the values of the corresponding physically observable nodes and identifying the value of the hidden node based on the correspondence between the corresponding physically observable nodes and the hidden node.

Method and apparatus tracing any node of an emulation

A scalable multi-level multi-stage network topology is employed to interconnect reconfigurable logic elements within the special purpose FPGA, inter-FPGA, inter-logic boards, and inter-backplanes. More specifically, under the presently preferred embodiment, an on-chip 3-stage inter-logic element crossbar network is provided to each special purpose FPGA for interconnecting the reconfigurable logic elements and the I/O pins of the special purpose FPGA. A two level three-stage inter-FPGA hybrid crossbar network is provided to interconnect the special purpose FPGAs and I/O pins of the logic board. The two-level three-stage inter-FPGA hybrid crossbar network consists of two stages of programmable crossbars and one stage of one or more special purpose FPGAs used for interconnection only. The exact number of special purpose FPGAs to be used for interconnection only on a particular logic board is dependent on the specific circuit design being emulated. A two-level two-stage inter-board crossbar network is provided to interconnect the logic boards or I/O boards for interconnecting the logic elements to external devices. Finally, a single-stage inter-backplane network and a number of PCBs are provided to interconnect multi-backplanes to form a multi-crate system.

Emulation system having a scalable multi-level multi-stage hybrid

Method and apparatus for tracing any node of an emulation

An emulation system is constituted with a plurality of FPGAs having on-chip integrated debugging facilities, distributively disposed on a plurality of circuit boards. Each FPGA's on-chip integrated debugging facilities include in particular, a scan register for outputting trace data, and comparison circuitry for generating inputs for a plurality of system triggers. Correspondingly, each board is provided with a plurality of trace memory for recording the trace data, and summing circuitry for generating partial sums for the triggers. The relative memory location within a clock cycle of trace data where the output of a LE will be recorded is predeterminable. Additionally, a system sync memory is provided for storing a plurality of sync patterns to facilitate reconstitution of trace data of a trace session. Lastly, the compilation or mapping software is enhanced to generate a cross-reference file cross referencing each circuit element in a circuit design to the predeterminable relative memory location within a clock cycle of trace data where the trace data for the particular circuit element can be found. Together, these elements allow fully visible tracing to be performed for an emulation.

Method and apparatus for performing fully visible tracing of an emulation

A scalable multi-level multi-stage network topology is employed to interconnect reconfigurable logic elements within the FPGA, inter-FPGA, interlogic boards, and inter-backplanes. More specifically, under the presently preferred embodiemnt, an on-chip 3-stage inter-logic element crossbar network is provided to each FPGA for interconnecting the reconfigurable logic elements and the I/O pins of the FPGA. A two level two-stage inter-FPGA crossbard network is provided to interconnect the FPGAs and I/O pins of the logic board. A two-level two-stage inter-board crossbar network is provided to interconnect the logic boards or I/O boards for interconnecting the logic elements to external devices. Finally, a single-stage inter-backplane network and a number of PCBs are provided to interconnect multi-backplanes to form a multi-crate system.

Growing community of inventors

Montpellier, France

Jean Barbier