10,753 research outputs found

    Development and analysis of a verstile, reusable, high speed, DMA controller for custom embedded applications using the PCI bus

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    This thesis investigates the plausibility of designing and developing a versatile, reusable, high speed interface for custom computing applications, based on the Peripheral Component Interface (PCI) Bus. A PCI I/O board was developed, utilizing mainly Complex Programmable Logic Devices (CPLD\u27s), which included a custom Direct Memory Access (DMA) Controller to take advantage of the unique feature set of the PCI bus. The arbitration mechanisms and performance characteristics of the PCI bus are taken advantage of in order to achieve a maximum burst throughput rate of 66 Megabytes per second. Performance characteristics of the I/O board are analyzed for two separate PCI host systems. In the faster of the two systems, a 166MHz Pentium PC, a maximum aggregate throughput rate of 54 Megabytes per second for PCI burst writes was achieved. In all cases throughput increased as a function of transfer size. Due to buffering implementations in the host systems write performance was always superior to read performance. In addition to exceptional throughput capability, this implementation provides a design engineer with a versatile interface which can be mated to a number of high performance applications. The PCI I/O board\u27s external interface is implemented with a CPLD which can be quickly and easily modified to meet the needs of practically any custom interface without decreasing PCI bus performance. Using the on-board latency timer and programmable FIFO\u27s the board can be fine tuned to meet a variety of application requirements. The two main design goals were to provide unlimited bursting capability and to transfer 32-bits of data on every clock. The first was achieved through the implementation of a 32-bit burst Transfer Count register. The second goal had to be reduced by 50% due to a timing margin violation discovered during board debug

    FPGA BASED TIMING MODULE AND OPTICAL COMMUNICATION CARD DESIGN FOR SPALLATION NEUTRON SOURCE

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    The Timing Module and Optical Communication Card (OCC) are used for acquisition of neutron event data by the instrument systems at the Spallation Neutron Source (SNS) neutron scattering facility. The instrument systems produce a very large flux of neutrons of varying energies over a short time period through the spallation process. The Timing Module and OCC require high-bandwidth communication to ensure high-speed data movement to the memory in the data collection system without loss of neutron data. The existing implementations use a standard PCI-X bus interface to transfer the data between the cards and the host computer. The data processing on the existing cards is implemented in a Xilinx Virtex-II FPGA. The bandwidth restrictions of the PCI-X bus and the logic constraints of the Virtex-II FPGA have resulted in limited capabilities of the instrument systems. New designs for the timing and communication modules that will improve performance, avoid data loss, and provide for future logic expansion are desired. In this project, we redesign the Timing Module and OCC moving from a PCI-X to PCI-Express bus interface to improve the data acquisition bandwidth. The new design also uses a Xilinx Virtex-5 FPGA to allow more channels to be processed per card and provide for further expansion. Further, the Virtex-5 device also has an embedded PCI-Express Hard IP core. This internal core simplifies the Printed Circuit Board (PCB) design since there is no external PCI interface chip required and decreases the probability of errors between the PCI interface and user logic design. The Timing Module implements a simple PCI Express read and write for the data transfer. The OCC requires a higher data rate than the Timing Module and therefore uses a more complex bus master direct memory access (DMA) for the endpoint PCI-Express block, which allows for lower CPU utilization and higher performance. New user logic interfaces were designed to integrate the PCI-Express endpoint with the Timing Module and the OCC logic designs. A single PCB was designed to function as both the Timing Module and OCC. The logic designs were verified by both functional simulation and in-system JTAG signal capture on the new PCB. The results indicate that our design provides efficient data transfer, higher throughput, and scalability, benefitting both modules and meeting design requirements

    Application of bus emulation techniques to the design of a PCI/MC68000 bridge

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    Bridges easy the interconnection and communication of devices that operate using different buses. In fact, we can see a computer as a hierarchy of buses to which devices are connected. In this paper we design a PCI/MC68000 bridge in order to improve communications between a Personal Computer and a MC68000 based system. The previous interface between both devices was based on the old 16-bit ISA bus, which represented a bottleneck in their communication. However, the methodology described here is generic and can be applied to the design of PCI bridges to other buses. We finish this work with an analysis of the bridge performance improvement which can also be easily adapted to other situations. As an example our interface is used in an interesting situation, i.e., updating the obsolete control unit of a highly valuable system (an industrial robot)

    PCI Based Read-out Receiver Card in the ALICE DAQ System

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    The Detector Data Link (DDL) is the high-speed optical link for the ALICE experiment. This link shall transfer the data coming from the detectors at 100 MB/s rate. The main components of the link have been developed: the destination Interface Unit (DIU), the Source Interface Unit (SIU) and the Read-out Receiver Card (RORC). The first RORC version is based on the VME bus. The performance tests show that the maximum VME bandwidth could be reached. Meanwhile the PCI bus became very popular and is used in many platforms. The development of a PCI-based version has been started. The document describes the prototype version in three sections. An overview explains the main purpose of the card: to provide an interface between the DDL and the PCI bus. Acting as a 32bit/33MHz PCI master the card is able to write or read directly to or from the system memory from or to the DDL, respectively. Beside these functions the card can also be used as an autonomous data generator. The card has been designed to be well adapted to applications, which require small software overhead such the high-speed data acquisition systems. The implementation of the firmware will be presented. For the logic design we are using VHDL and schematic draw. Software library routines were written in C and are available on Linux OS. The results of performance measurements will be available to allow the comparison between the VME-RORC and PCI-RORC. In the conclusion the future plans and the idea of the improved (64bit/66MHz) PCI-RORC will be shown

    The development of a node for a hardware reconfigurable parallel processor

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    This dissertation concerns the design and implementation of a node for a hardware reconfigurable parallel processor. The hardware that was developed allows for the further development of a parallel processor with configurable hardware acceleration. Each node in the system has a standard microprocessor and reconfigurable logic device and has high speed communications channels for inter-node communication. The design of the node provided high-speed serial communications channels allowing the implementation of various network topographies. The node also provided a PCI master interface to provide an external interface and communicate with local nodes on the bus. A high speed RlSC processor provided communication and system control functions and the reconfigurable logic device provided communication interfaces and data processing functions. The node was designed and implemented as a PCI card that interfaced a standard PCI bus. VHDL designs for logic devices that provided system support were developed, VHDL designs for the reconfigurable logic FPGA and software including drivers and system software were written for the node. The 64-bit version Linux operating system was then ported to the processor providing a UNIX environment for the system. The node functioned as specified and parallel and hardware accelerated processing was demonstrated. The hardware acceleration was shown to provide substantial performance benefits for the system

    Design and implementation of an electro-optical backplane with pluggable in-plane connectors

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    The design, implementation and characterisation of an electro-optical backplane and an active pluggable in-plane optical connector technology is presented. The connection architecture adopted allows line cards to be mated to and unmated from a passive electro-optical backplane with embedded polymeric waveguides. The active connectors incorporate a photonics interface operating at 850 nm and a mechanism to passively align the interface to the optical waveguides embedded in the backplane. A demonstration platform has been constructed to assess the viability of embedded electro-optical backplane technology in dense data storage systems. The demonstration platform includes four switch cards, which connect both optically and electronically to the electro-optical backplane in a chassis. These switch cards are controlled by a single board computer across a Compact PCI bus on the backplane. The electrooptical backplane is comprised of copper layers for power and low speed bus communication and one polymeric optical layer, wherein waveguides have been patterned by a direct laser writing scheme. The optical waveguide design includes densely arrayed multimode waveguides with a centre to centre pitch of 250μm between adjacent channels, multiple cascaded waveguide bends, non-orthogonal crossovers and in-plane connector interfaces. In addition, a novel passive alignment method has been employed to simplify high precision assembly of the optical receptacles on the backplane. The in-plane connector interface is based on a two lens free space coupling solution, which reduces susceptibility to contamination. Successful transfer of 10.3 Gb/s data along multiple waveguides in the electro-optical backplane has been demonstrated and characterised

    Transient Pulse Monitor

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    This project involved the design of a new Transient Pulse Monitor (TPM) for the recording of key characteristics of lightning strikes and other transient pulses in the vicinity of spacecraft launch sites, to be used in a comprehensive Online Lightning Monitoring System (OLMS). This report documents the design for implementation on Signatec Digitizer boards, using an internal FPGA for processing, a 16-bit ADC to read sensor signals, and a PCI-X bus to interface with a central server. The design was completed using VHDL and Verilog and simulated. Progress was also made in debugging of the code on the physical FPGA

    AER Neuro-Inspired interface to Anthropomorphic Robotic Hand

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    Address-Event-Representation (AER) is a communication protocol for transferring asynchronous events between VLSI chips, originally developed for neuro-inspired processing systems (for example, image processing). Such systems may consist of a complicated hierarchical structure with many chips that transmit data among them in real time, while performing some processing (for example, convolutions). The information transmitted is a sequence of spikes coded using high speed digital buses. These multi-layer and multi-chip AER systems perform actually not only image processing, but also audio processing, filtering, learning, locomotion, etc. This paper present an AER interface for controlling an anthropomorphic robotic hand with a neuro-inspired system.Unión Europea IST-2001-34124 (CAVIAR)Ministerio de Ciencia y Tecnología TIC-2003-08164-C03-02Ministerio de Ciencia y Tecnología TIC2000-0406-P4- 0
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