DMA - Direct Memory Access
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System Buses EE2222 Computer Interfacing and Microprocessors
System Buses EE2222 Computer Interfacing and Microprocessors Partially based on Computer Organization and Architecture by William Stallings Computer Electronics by Thomas Blum 2020 EE2222 1 Connecting • All the units must be connected • Different type of connection for different type of unit • CPU • Memory • Input/Output 2020 EE2222 2 CPU Connection • Reads instruction and data • Writes out data (after processing) • Sends control signals to other units • Receives (& acts on) interrupts 2020 EE2222 3 Memory Connection • Receives and sends data • Receives addresses (of locations) • Receives control signals • Read • Write • Timing 2020 EE2222 4 Input/Output Connection(1) • Similar to memory from computer’s viewpoint • Output • Receive data from computer • Send data to peripheral • Input • Receive data from peripheral • Send data to computer 2020 EE2222 5 Input/Output Connection(2) • Receive control signals from computer • Send control signals to peripherals • e.g. spin disk • Receive addresses from computer • e.g. port number to identify peripheral • Send interrupt signals (control) 2020 EE2222 6 What is a Bus? • A communication pathway connecting two or more devices • Usually broadcast (all components see signal) • Often grouped • A number of channels in one bus • e.g. 32 bit data bus is 32 separate single bit channels • Power lines may not be shown 2020 EE2222 7 Bus Interconnection Scheme 2020 EE2222 8 Data bus • Carries data • Remember that there is no difference between “data” and “instruction” at this level • Width is a key determinant of performance • 8, 16, 32, 64 bit 2020 EE2222 9 Address bus • Identify the source or destination of data • e.g. CPU needs to read an instruction (data) from a given location in memory • Bus width determines maximum memory capacity of system • e.g. -
ECESATUSB1 This Expresscard Power Esata Port Controller Card
1 Port ExpressCard Power eSATA Controller Adapter Card StarTech ID: ECESATUSB1 This ExpressCard Power eSATA port controller card can be installed in an available ExpressCard 34/54 mm slot to provide a powered eSATA connection, and also alternatively provide either external SATA (data only) or USB 2.0 connectivity from one uniquely designed port if using with standard eSATA or USB devices. An ideal solution for using an eSATA SSD Flash drive on your laptop, the power eSATA card delivers both a high speed eSATA connection and power from the combined USB port. A versatile connectivity solution, the card features built-in port multiplier support, allowing multi-drive eSATA storage enclosures to be connected to the host computer using a single eSATA cable. Taking advantage of the transfer speed of eSATA connection and the 5V power output of the USB 2.0 port, the ExpressCard Power eSATA adapter is the perfect answer for connecting compatible mobile drive enclosures, similar to the built-in power eSATA port provided by the following laptop computers: Toshiba: Satellite E105, A350, Satellite Pro P300; Qosmio G50, X305, Portege A600, M750, R500, R600; and Tecra M10, R10, A10. Dell: Studio 15, 17; Latitude E6400, E6500; Precision M2400, M4400, M6400, M6400 Covet. Applications Connects to eSATA SSD Flash drives, such as OCZ Throttle, Kangaru e-Flash drives and Ridata Racer series flash drives Provides connectivity between Notebooks and PCs with ExpressCard slots to external drive enclosures with Power eSATA (eSATA+USB) port, or with regular eSATA -
Computer Bus Characteristics
Upendra Sharma (upsharma.in) Computer Bus A bus, in computing, is a set of physical connections (cables, printed circuits, etc.) which can be shared by multiple hardware components in order to communicate with one another. The purpose of buses is to reduce the number of "pathways" needed for communication between the components, by carrying out all communications over a single data channel. This is why the metaphor of a "data highway" is sometimes used. If only two hardware components communicate over the line, it is called a hardware port (such as a serial port or parallel port). Characteristics A bus is characterised by the amount of information that can be transmitted at once. This amount, expressed in bits, corresponds to the number of physical lines over which data is sent simultaneously. A 32-wire ribbon cable can transmit 32 bits in parallel. The term "width" is used to refer to the number of bits that a bus can transmit at once. Additionally, the bus speed is also defined by its frequency (expressed in Hertz), the number of data packets sent or received per second. Each time that data is sent or received is called a cycle. This way, it is possible to find the maximum transfer speed of the bus, the amount of data which it can transport per unit of time, by multiplying its width by its frequency. A bus with a width of 16 bits and a frequency of 133 MHz, therefore, has a transfer speed equal to: Upendra Sharma (upsharma.in) Types of Buses In reality, each bus is generally constituted of 50 to 100 distinct physical lines, divided into three subassemblies: The address bus (sometimes called the memory bus) transports memory addresses which the processor wants to access in order to read or write data. -
Input/Output
Lectures 24: Input/Output I. External devices A. External devices are not connected directly to the system bus because they have a wide range of control logics, as well as data transfer speeds and formats. B. Virtually all external devices have buffers, control signals, status signals, and data bits. C. Those that deal with other forms of energy have transducers that converts from non-electrical data to electrical data, (e.g. key press to ASCII in a keyboard), or electrical data to non-electrical data (e.g. bytes to light in a monitor). D. In the past, intra-system (less than 1 meter) connections were usually parallel, and inter-system were serial. Now almost all are serial. 1. To convert from parallel to serial use a shift register. 2. USB (universal serial bus) is a common standard for serial transmission with USB 3.0 transferring at 5Gb/s. II. I/O Modules (south bridge and north bridge on a PC) on the motherboard provide the logic, buffers, error detection, and ports to communicate with the external devices on one side, and a system-type bus on the other. For external device interfaces, the modules have data, status, and control lines. For the system bus they have data, address, and control lines. The south bridge handles slower I/O devices and is connected to the north bridge rather than the system bus directly. III. Programmed I/O A. Overview of Programmed I/O waits for the processor to query it. B. Four types of I/O commands: 1) control (e.g. -
2 Port Flush Mount Expresscard 54Mm Superspeed USB 3.0 Card Adapter Startech ID: ECUSB3S254F
2 Port Flush Mount ExpressCard 54mm SuperSpeed USB 3.0 Card Adapter StarTech ID: ECUSB3S254F The ECUSB3S254F 2-Port Flush Mount USB 3.0 ExpressCard Adapter uses a unique form factor design that allows it to sit fully in a standard 54mm laptop ExpressCard slot without sticking out. When inserted, the USB 3.0 ports provided by the ExpressCard adapter sit flush with the sides of the laptop, creating a seamless add-on that can be left installed even while on the move, without having to worry about impact damage to either the card or the ExpressCard slot. The SuperSpeed USB 3.0 Card supports data transfer rates of up to 5Gbps, and is backward compatible with USB 2.0 (at up to 480Mbps), or USB 1.1/1.0 at up to 12/1.5 Mbps respectively - the perfect laptop accessory for users to connect USB devices, both new and old. Applications Users who need USB connectivity, but do not need to swap between other ExpressCard adapters, so will leave the card installed in the card slot Mobile users who want to leave ExpressCard adapters installed, without worry about damaging the card or slot while on the move Connect high performance USB 3.0 external storage devices to a laptop Upgrade an older laptop with USB 3.0 connectivity Expand on your laptop expansion capabilities with additional USB ports Features Unique flush-mount form factor design Two SuperSpeed USB 3.0 compliant ports with support for transfer rates up to 5 Gbps Backward compatible with USB 2.0/1.x devices Compliant with USB 3.0 base specification 1.0 and xHCI specification 0.95 Compliant with -
Direct Memory Access
International Journal of Research in Science And Technology http://www.ijrst.com (IJRST) 2014, Vol. No. 4, Issue No. III, Jul-Sep ISSN: 2249-0604 DIRECT MEMORY ACCESS LokeshMadan1, KislayAnand2and Bharat Bhushan3 1Department of Computer Science, Dronacharya College of Engineering, Gurgaon, India 2Department of Computer Science, Dronacharya College of Engineering, Gurgaon, India 3Department of Computer Science, Dronacharya College of Engineering, Gurgaon, India ABSTRACT Direct Memory Access (DMA) is a feature in all modern computers that allow devices to be able to move large blocks of data without any interaction with the processor. This can be useful, as you may have already seen from the floppy programming chapter. While the device transfers the block of data, the processor is free to continue running the software without worry about the data being transferred into memory, or to another device. The basic idea is that we can schedule the DMA device to perform the task on its own. Different buses and architecture designs have different methods of performing direct memory access. KEYWORDS: Processor register,cyclestealing,busmastering,countregisters,interleaved,c ache invalidation, schematics, gigabit Ethernet. INTRODUCTION A DMA controller can generate memory addresses and initiate memory read or write cycles. It contains several processor registers that can be written and read by the CPU. These include a memory address register, a byte count register, and one or more control registers. The control registers specify the I/O port to use, the direction of the transfer (reading from the I/O device or writing to the I/O device), the transfer unit (byte at a time or word at a time), and the number of bytes to transfer in one burst. -
Tcss 422: Operating Systems
TCSS 422 A – Fall 2018 12/6/2018 School of Engineering and Technology, TCSS 422: OPERATING SYSTEMS Beyond Physical Memory, I/O Devices Wes J. Lloyd School of Engineering and Technology, University of Washington - Tacoma TCSS422: Operating Systems [Fall 2018] December 5, 2018 School of Engineering and Technology, University of Washington - Tacoma FEEDBACK FROM 12/3 Program 3 Write to a proc file? Once we have a reference to a process, we then traverse pages on that process? TCSS422: Operating Systems [Fall 2018] December 5, 2018 L19.2 School of Engineering and Technology, University of Washington - Tacoma FEEDBACK - 2 Which I/O Devices work better with interrupts (other than keyboard)? Interrupt driven I/O - - is off-loaded from the CPU . Via Directory Memory Access (DMA) controller . CPU non involved in the data transfer . Interrupts enable a context-switch to notify data is available . Examples: ISA, PCI bus Polled I/O is - - programmed I/O Data transfers fully occupy CPU for entire data transfer CPU unavailable for other work Examples: ATA (parallel ports), legacy serial/parallel ports, PS/2 keyboard/mouse, MIDI, joysticks TCSS422: Operating Systems [Fall 2018] December 5, 2018 L19.3 School of Engineering and Technology, University of Washington - Tacoma Slides by Wes J. Lloyd L19.1 TCSS 422 A – Fall 2018 12/6/2018 School of Engineering and Technology, FEEDBACK - 3 Does the mouse use interrupts, polling, or a hybrid of both? . Interrupts . Where is the polling (BUSY) process? (see top –d .1) TCSS422: Operating Systems [Fall 2018] December 5, 2018 L19.4 School of Engineering and Technology, University of Washington - Tacoma CLOUD AND DISTRIBUTED SYSTEMS RESEARCH L19.5 CLOUD AND DISTRIBUTED SYSTEMS LAB WES LLOYD, [email protected], HTTP://FACULTY.WASHINGTON.EDU/WLLOYD Serverless Computing (FaaS): How should cloud native applications be composed from microservices to optimize performance and cost? Code structure directly influences hosting costs. -
Setting up MPU-401 and Compatible Cards on Your PC
® Supplemental RAP-10 ®ÂØÒňΠRoland Audio Producer Notes May 21, 1996 Installing the RAP-10 in Windows 95 These notes are designed to help you install the Roland Audio Production Card (RAP-10) and configure it for use in Windows 95. This process will consist of the following four steps: I. First, we will look at computers and peripherals and how they work together. See “Typical Hardware Setup”. II. Second, we will prepare the RAP-10 for installation. See “Changing Hardware Settings”. III. Third, we will install the Windows software. See “Installing the Roland Audio Tools Software”. IV. Finally, we will test the RAP-10 to make sure it has been installed properly. See “Testing the RAP-10 Card”. If you were previously using the RAP-10 successfully under Windows 3.1 in the same computer, you can skip the first two steps and go directly to Section III. I. Typical Hardware Setup Interrupts and Addresses IBM-compatible computers can be expanded to accept many different devices such as a mouse, modem, printer, sound card, or MIDI card. Your computer uses interrupts (also called IRQs) and port addresses (or I/O addresses) to distinguish between these different devices. Since this guide is not intended to explain the concepts of IBM computers in detail, we will not jump into the particular definitions of IRQs and addresses. Just remember that the IRQ and port address numbers must be unique for EVERY device in your computer. DMA Channels The RAP-10 card also uses two DMA channels (Direct Memory Access) for the recording and playback of digital audio. -
Computer Service Technician- CST Competency Requirements
Computer Service Technician- CST Competency Requirements This Competency listing serves to identify the major knowledge, skills, and training areas which the Computer Service Technician needs in order to perform the job of servicing the hardware and the systems software for personal computers (PCs). The present CST COMPETENCIES only address operating systems for Windows current version, plus three older. Included also are general common Linux and Apple competency information, as proprietary service contracts still keep most details specific to in-house service. The Competency is written so that it can be used as a course syllabus, or the study directed towards the education of individuals, who are expected to have basic computer hardware electronics knowledge and skills. Computer Service Technicians must be knowledgeable in the following technical areas: 1.0 SAFETY PROCEDURES / HANDLING / ENVIRONMENTAL AWARENESS 1.1 Explain the need for physical safety: 1.1.1 Lifting hardware 1.1.2 Electrical shock hazard 1.1.3 Fire hazard 1.1.4 Chemical hazard 1.2 Explain the purpose for Material Safety Data Sheets (MSDS) 1.3 Summarize work area safety and efficiency 1.4 Define first aid procedures 1.5 Describe potential hazards in both in-shop and in-home environments 1.6 Describe proper recycling and disposal procedures 2.0 COMPUTER ASSEMBLY AND DISASSEMBLY 2.1 List the tools required for removal and installation of all computer system components 2.2 Describe the proper removal and installation of a CPU 2.2.1 Describe proper use of Electrostatic Discharge -
FLEXBUS: a High-Performance System-On-Chip Communication
34.4 FLEXBUS: A High-Performance System-on-Chip Communication Architecture with a Dynamically Configurable Topology ∗ Krishna Sekar Kanishka Lahiri Anand Raghunathan Sujit Dey Dept. of ECE NEC Laboratories America NEC Laboratories America Dept. of ECE UC San Diego, CA 92093 Princeton, NJ 08540 Princeton, NJ 08540 UC San Diego, CA 92093 [email protected] [email protected] [email protected] [email protected] ABSTRACT portunities for dynamically controlling the spatial allocation of com- munication architecture resources among different SoC components, In this paper, we describe FLEXBUS, a flexible, high-performance on- chip communication architecture featuring a dynamically configurable a capability, which if properly exploited, can yield substantial per- formance gains. We also describe techniques for choosing optimized topology. FLEXBUS is designed to detect run-time variations in com- munication traffic characteristics, and efficiently adapt the topology of FLEXBUS configurations under time-varying traffic profiles. We have the communication architecture, both at the system-level, through dy- conducted detailed experiments on FLEXBUS using a commercial de- namic bridge by-pass, as well as at the component-level, using compo- sign flow to analyze its area and performance under a wide variety of system-level traffic profiles, and applied it to an IEEE 802.11 MAC nent re-mapping. We describe the FLEXBUS architecture in detail and present techniques for its run-time configuration based on the char- processor design. The results demonstrate that FLEXBUS provides up acteristics of the on-chip communication traffic. The techniques un- to 31.5% performance gains compared to conventional architectures, with negligible hardware overhead. -
PDP-11 Bus Handbook (1979)
The material in this document is for informational purposes only and is subject to change without notice. Digital Equipment Corpo ration assumes no liability or responsibility for any errors which appear in, this document or for any use made as a result thereof. By publication of this document, no licenses or other rights are granted by Digital Equipment Corporation by implication, estoppel or otherwise, under any patent, trademark or copyright. Copyright © 1979, Digital Equipment Corporation The following are trademarks of Digital Equipment Corporation: DIGITAL PDP UNIBUS DEC DECUS MASSBUS DECtape DDT FLIP CHIP DECdataway ii CONTENTS PART 1, UNIBUS SPECIFICATION INTRODUCTION ...................................... 1 Scope ............................................. 1 Content ............................................ 1 UNIBUS DESCRIPTION ................................................................ 1 Architecture ........................................ 2 Unibus Transmission Medium ........................ 2 Bus Terminator ..................................... 2 Bus Segment ....................................... 3 Bus Repeater ....................................... 3 Bus Master ........................................ 3 Bus Slave .......................................... 3 Bus Arbitrator ...................................... 3 Bus Request ....................................... 3 Bus Grant ......................................... 3 Processor .......................................... 4 Interrupt Fielding Processor ......................... -
~ ARTISAN® with Experienced Engineers and Technicians on Staff
Full-service, independent repair center -~ ARTISAN® with experienced engineers and technicians on staff. TECHNOLOGY GROUP ~I We buy your excess, underutilized, and idle equipment along with credit for buybacks and trade-ins. Custom engineering Your definitive source so your equipment works exactly as you specify. for quality pre-owned • Critical and expedited services • Leasing / Rentals/ Demos equipment. • In stock/ Ready-to-ship • !TAR-certified secure asset solutions Expert team I Trust guarantee I 100% satisfaction Artisan Technology Group (217) 352-9330 | [email protected] | artisantg.com All trademarks, brand names, and brands appearing herein are the property o f their respective owners. Find the Measurement Computing / CEC PC-488 at our website: Click HERE Program and documentation copyrighted 1986, 1998, 2003 by Capital Equipment Corporation (CEC). The software interpreter contained in EPROM/ROM is copyrighted and all rights are reserved by Capital Equipment Corporation. Copying or duplicating this product is a violation of law. Application software libraries provided on disk are copyrighted by Capital Equipment Corporation. The purchaser is granted the right to include portions of this software in products which use one of CEC's IEEE-488 interface boards (including those sold through resellers such as Keithley Instruments, etc.). The software may not be distributed other than for the application just mentioned. Purchasers of this product may copy and use the programming examples contained in this book. No other parts of this book may be reproduced or transmitted in any form or by any means, electronic, optical, or mechanical, including photocopying and recording, or by any information storage and retrieval system, without permission in writing from Capital Equipment Corporation.