Altera Corporation

Neil Kenneth Thorne

Andrew Martyn Draper

Paul Metzgen

Roger May

Martin Langhammer

A memory controller has a first interface, for connection to an external memory device; a second interface, for connection to at least one other component; and a third JTAG interface, for connection to an external user device. The memory controller further includes a processor, which performs calibration processes, in order to synchronize operations of the memory controller and the external memory device, and also runs test software for testing operation of the first interface and the external memory device, and for providing test results to the external user device over the third interface. The memory controller further includes an internal memory, for storing the instructions defining the test software.

Debugging external interface

There is provided a method for generating a table for reordering the output of a Fourier transform, the Fourier transform being performed on a predefined number of input samples, the method comprising performing one or more decomposition stages on a sequence corresponding in number to the predefined number of input samples to form a representation of the output of the Fourier transform; wherein at least one of the decomposition stages comprises a composite operation that is equivalent to two or more operations; and rearranging the representation of the output of the Fourier transform to generate a reordering table.

Reordering discrete fourier transform outputs

Methods and apparatus for programmable logic devices including embedded processors having a dual-port SRAMs. A programmable logic integrated circuit includes a programmable logic portion having a plurality of logic elements, programmably configurable to implement user-defined combinatorial or registered logic functions, and an embedded processor portion coupled to the programmable logic portion. The embedded processor portion includes a processor, and a memory block coupled to the processor. The memory block includes a first plurality of memory cells for storing data, a second plurality of memory cells for storing data, a first port coupled to the first and second pluralities of memory cells, a second port coupled to the first and second pluralities of memory cells, and an arbiter coupled to the first port and the second port. When the second port is accessing the first plurality of memory cells, the arbiter prevents the first port from accessing the first plurality of memory cells, and when the second port is accessing the first plurality of memory cells, the arbiter allows the first port to access the second plurality of memory cells.

Embedded processor with dual-port SRAM for programmable logic

A source synchronous external memory device returns data to a memory controller of an electronic device with its own clock signal, which allows the returned data to be captured with a high degree of accuracy. The captured data must then be resynchronized with the clock signal which controls the other components of the electronic device. This problem is particularly acute in the case of high speed memory devices, such as DDR (Double Data Rate) memory devices, and similar memory devices. Test data is written to the external memory device, and is then read back several times. Attempts are made to resynchronize the captured data with the system clock, with different relative variations in the phase of the captured data and the system clock, in order to select a value for the relative phase, which allows for optimum resynchronization.

Dynamic phase alignment for resynchronization of captured data

Delays through components of a programmable device are determined transparently to the user through the use of mimic paths. For each delay path to be measured, at least one mimic path is created that has similar components and characteristics to the actual path to be measured. A signal fed through this mimic path will experience similar delay to a signal passing through the actual path, which can be affected by temperature and voltage variations during operation. A swept clock signal can be passed to a register latching the mimic signal data, producing output that can be fed to lead/lag logic to determine a current value of the delay through the mimic path. This delay can be compared to a previous delay determination to approximate an adjustment to be made to a sampling clock used to latch the actual data into the appropriate register at the middle of the latching window.

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London, United Kingdom

Neil Kenneth Thorne