I/O User's Reference Manual

Total Page:16

File Type:pdf, Size:1020Kb

I/O User's Reference Manual VSI OpenVMS I/O User’s Reference Manual Document Number: DO-DIOURM-01A Publication Date: August 2019 This manual is intended for system programmers who want to take advantage of the time and space savings that result from direct use of I/O drivers. OpenVMS users who do not require such detailed knowledge of I/O drivers can use the device-inde- pendent services described in the OpenVMS Record Management Services Refer- ence Manual. Revision Update Information: This is a new manual. Operating System and Version: VSI OpenVMS I64 Version 8.4-1H1 VSI OpenVMS Alpha 8.4-2L1 VMS Software, Inc. (VSI) Bolton, Massachusetts, USA I/O User’s Reference Manual: Copyright © 2019 VMS Software, Inc. (VSI), Bolton, Massachusetts, USA Legal Notice Confidential computer software. Valid license from VSI required for possession, use or copying. Consistent with FAR 12.211 and 12.212, Commercial Computer Software, Computer Software Documentation, and Technical Data for Commercial Items are licensed to the U.S. Government under vendor's standard commercial license. The information contained herein is subject to change without notice. The only warranties for VSI products and services are set forth in the express warranty statements accompanying such products and services. Nothing herein should be construed as constituting an additional warranty. VSI shall not be liable for technical or editorial errors or omissions contained herein. HPE, HPE Integrity, HPE Alpha, and HPE Proliant are trademarks or registered trademarks of Hewlett Packard Enterprise. Intel, Itanium and IA-64 are trademarks or registered trademarks of Intel Corporation or its subsidiaries in the United States and other coun- tries. Java, the coffee cup logo, and all Java based marks are trademarks or registered trademarks of Oracle Corporation in the United States or other countries. Kerberos is a trademark of the Massachusetts Institute of Technology. Microsoft, Windows, Windows-NT and Microsoft XP are U.S. registered trademarks of Microsoft Corporation. Microsoft Vista is either a registered trademark or trademark of Microsoft Corporation in the United States and/or other countries. Motif is a registered trademark of The Open Group UNIX is a registered trademark of The Open Group. The VSI OpenVMS documentation set is available on DVD. ii I/O User’s Reference Manual Preface .................................................................................................................................... xi 1. About VSI ..................................................................................................................... xi 2. Intended Audience ......................................................................................................... xi 3. Document Structure ....................................................................................................... xi 4. Device Driver Support for OpenVMS Alpha and Integrity servers 64-Bit Addressing ........ xii 5. About VSI OpenVMS Alpha VXXXXXXXX ................................................................ xii 6. Typographical Conventions .......................................................................................... xiii 7. VSI Encourages Your Comments .................................................................................. xiv 8. How to Order Additional Documentation ...................................................................... xiv Chapter 1. ACP-QIO Interface ............................................................................................ 1 1.1. ACP Functions and Encoding ....................................................................................... 2 1.2. File Information Block (FIB) ........................................................................................ 3 1.3. ACP Subfunctions ........................................................................................................ 7 1.3.1. Directory Lookup .............................................................................................. 8 1.3.1.1. Input Parameters ..................................................................................... 8 1.3.1.2. Operation ............................................................................................... 9 1.3.1.3. Directory Entry Protection ..................................................................... 11 1.3.2. Access ............................................................................................................ 11 1.3.2.1. Input Parameters ................................................................................... 11 1.3.2.2. Operation ............................................................................................. 12 1.3.3. Extend ............................................................................................................ 12 1.3.3.1. Input Parameters ................................................................................... 12 1.3.3.2. Operation ............................................................................................. 14 1.3.4. Truncate .......................................................................................................... 14 1.3.4.1. Input Parameters ................................................................................... 14 1.3.4.2. Operation ............................................................................................. 15 1.3.5. Read/Write Attributes ...................................................................................... 15 1.3.5.1. Input Parameters ................................................................................... 16 1.3.5.2. Attribute Descriptions ........................................................................... 19 1.4. ACP-QIO Record Attributes Area ............................................................................... 21 1.5. ACP-QIO Attributes Statistics Block ........................................................................... 23 1.6. Major Functions ......................................................................................................... 24 1.6.1. Create File ...................................................................................................... 24 1.6.1.1. Input Parameters ................................................................................... 25 1.6.1.2. Disk ACP Operation ............................................................................. 26 1.6.1.3. Directory Entry Creation ....................................................................... 27 1.6.1.4. Magnetic Tape ACP Operation .............................................................. 27 1.6.2. Access File ...................................................................................................... 27 1.6.2.1. Input Parameters ................................................................................... 28 1.6.2.2. Operation ............................................................................................. 29 1.6.3. Deaccess File .................................................................................................. 29 1.6.3.1. Input Parameters ................................................................................... 29 1.6.3.2. Operation ............................................................................................. 29 1.6.4. Modify File ..................................................................................................... 30 1.6.4.1. Input Parameters ................................................................................... 30 1.6.4.2. Operation ............................................................................................. 30 1.6.5. Delete File ...................................................................................................... 31 1.6.5.1. Operation ............................................................................................. 31 1.6.6. Movefile Subfunction ...................................................................................... 32 1.6.6.1. Calling the Movefile Subfunction .......................................................... 32 1.6.7. Mount ............................................................................................................. 35 1.6.8. ACP Control ................................................................................................... 35 iii I/O User’s Reference Manual 1.6.8.1. Input Parameters ................................................................................... 35 1.6.8.2. Magnetic Tape Control Functions .......................................................... 36 1.6.8.3. Miscellaneous Disk Control Functions ................................................... 37 1.6.8.4. Disk Quotas .......................................................................................... 37 1.7. I/O Status Block ......................................................................................................... 39 Chapter 2. Disk Drivers ...................................................................................................... 41 2.1. Driver Features .......................................................................................................... 41 2.1.1. Data Check ..................................................................................................... 41 2.1.2. Effects of a Failure During an I/O Write Operation ............................................ 42 2.1.3.
Recommended publications
  • Digital Technical Journal, Number 3, September 1986: Networking
    Netwo;king Products Digital TechnicalJournal Digital Equipment Corporation Number 3 September I 986 Contents 8 Foreword William R. Johnson, Jr. New Products 10 Digital Network Architecture Overview Anthony G. Lauck, David R. Oran, and Radia J. Perlman 2 5 PerformanceAn alysis andModeling of Digital's Networking Architecture Raj Jain and William R. Hawe 35 The DECnetjSNA Gateway Product-A Case Study in Cross Vendor Networking John P:.. �orency, David Poner, Richard P. Pitkin, and David R. Oran ._ 54 The Extended Local Area Network Architecture and LANBridge 100 William R. Hawe, Mark F. Kempf, and Alan). Kirby 7 3 Terminal Servers on Ethernet Local Area Networks Bruce E. Mann, Colin Strutt, and Mark F. Kempf 88 The DECnet-VAXProduct -A n IntegratedAp proach to Networking Paul R. Beck and James A. Krycka 100 The DECnet-ULTRIXSoftware John Forecast, James L. Jackson, and Jeffrey A. Schriesheim 108 The DECnet-DOS System Peter 0. Mierswa, David). Mitton, and Ma�ha L. Spence 117 The Evolution of Network Management Products Nancy R. La Pelle, Mark). Seger, and Mark W. Sylor 129 The NMCCjDECnet Monitor Design Mark W. Sylor 1 Editor's Introduction The paper by Bill Hawe, Mark Kempf, and AI Kirby reports how studies of potential new broad­ band products led to the development of the Extended LAN Architecture. The design of the LANBridge 100, the first product incorporating that architecture, is described, along with the trade-offs made to achieve high performance. The speed of communication between terminals and systems depends on how they are connected. Bruce Mann, Colin Strutt, and Mark Kempf explain how they developed the LAT protocol to connect terminals to hosts on an Ethernet.
    [Show full text]
  • Openvms Record Management Services Reference Manual
    OpenVMS Record Management Services Reference Manual Order Number: AA-PV6RD-TK April 2001 This reference manual contains general information intended for use in any OpenVMS programming language, as well as specific information on writing programs that use OpenVMS Record Management Services (OpenVMS RMS). Revision/Update Information: This manual supersedes the OpenVMS Record Management Services Reference Manual, OpenVMS Alpha Version 7.2 and OpenVMS VAX Version 7.2 Software Version: OpenVMS Alpha Version 7.3 OpenVMS VAX Version 7.3 Compaq Computer Corporation Houston, Texas © 2001 Compaq Computer Corporation Compaq, AlphaServer, VAX, VMS, the Compaq logo Registered in U.S. Patent and Trademark Office. Alpha, PATHWORKS, DECnet, DEC, and OpenVMS are trademarks of Compaq Information Technologies Group, L.P. in the United States and other countries. UNIX and X/Open are trademarks of The Open Group in the United States and other countries. All other product names mentioned herein may be the trademarks of their respective companies. Confidential computer software. Valid license from Compaq required for possession, use, or copying. Consistent with FAR 12.211 and 12.212, Commercial Computer Software, Computer Software Documentation, and Technical Data for Commercial Items are licensed to the U.S. Government under vendor’s standard commercial license. Compaq shall not be liable for technical or editorial errors or omissions contained herein. The information in this document is provided "as is" without warranty of any kind and is subject to change without notice. The warranties for Compaq products are set forth in the express limited warranty statements accompanying such products. Nothing herein should be construed as constituting an additional warranty.
    [Show full text]
  • Software Product Description and Quickspecs
    VSI OpenVMS Alpha Version 8.4-2L2 Operating System DO-DVASPQ-01A Software Product Description and QuickSpecs PRODUCT NAME: VSI OpenVMS Alpha Version 8.4-2L2 DO-DVASPQ-01A This SPD and QuickSpecs describes the VSI OpenVMS Alpha Performance Release Operating System software, Version 8.4-2L2 (hereafter referred to as VSI OpenVMS Alpha V8.4-2L2). DESCRIPTION OpenVMS is a general purpose, multiuser operating system that runs in both production and development environments. VSI OpenVMS Alpha Version 8.4-2L2 is the latest release of the OpenVMS Alpha computing environment by VMS Software, Inc (VSI). VSI OpenVMS Alpha V8.4-2L2 is compiled to take advantage of architectural features such as byte and word memory reference instructions, and floating-point improvements, which are available only in HPE AlphaServer EV6 or later processors. This optimized release improves performance by taking advantage of faster hardware-based instructions that were previously emulated in software. NOTE: VSI OpenVMS Alpha V8.4-2L2 does not work on, and is not supported on, HPE AlphaServer pre-EV6 systems. OpenVMS Alpha supports HPE’s AlphaServer series computers. OpenVMS software supports industry standards, facilitating application portability and interoperability. OpenVMS provides symmetric multiprocessing (SMP) support for multiprocessing systems. The OpenVMS operating system can be tuned to perform well in a wide variety of environments. This includes combinations of compute-intensive, I/O-intensive, client/server, real-time, and other environments. Actual system performance depends on the type of computer, available physical memory, and the number and type of active disk and tape drives. The OpenVMS operating system has well-integrated networking, distributed computing, client/server, windowing, multi-processing, and authentication capabilities.
    [Show full text]
  • Name Description Files Notes See Also Colophon
    PTS(4) Linux Programmer’sManual PTS(4) NAME ptmx, pts − pseudoterminal master and slave DESCRIPTION The file /dev/ptmx is a character file with major number 5 and minor number 2, usually with mode 0666 and ownership root:root. It is used to create a pseudoterminal master and slave pair. When a process opens /dev/ptmx,itgets a file descriptor for a pseudoterminal master (PTM), and a pseu- doterminal slave (PTS) device is created in the /dev/pts directory.Each file descriptor obtained by opening /dev/ptmx is an independent PTM with its own associated PTS, whose path can be found by passing the file descriptor to ptsname(3). Before opening the pseudoterminal slave,you must pass the master’sfile descriptor to grantpt(3) and un- lockpt(3). Once both the pseudoterminal master and slave are open, the slave provides processes with an interface that is identical to that of a real terminal. Data written to the slave ispresented on the master file descriptor as input. Data written to the master is presented to the slave asinput. In practice, pseudoterminals are used for implementing terminal emulators such as xterm(1), in which data read from the pseudoterminal master is interpreted by the application in the same way a real terminal would interpret the data, and for implementing remote-login programs such as sshd(8), in which data read from the pseudoterminal master is sent across the network to a client program that is connected to a terminal or terminal emulator. Pseudoterminals can also be used to send input to programs that normally refuse to read input from pipes (such as su(1), and passwd(1)).
    [Show full text]
  • A Multiplatform Pseudo Terminal
    A Multi-Platform Pseudo Terminal API Project Report Submitted in Partial Fulfillment for the Masters' Degree in Computer Science By Qutaiba Mahmoud Supervised By Dr. Clinton Jeffery ABSTRACT This project is the construction of a pseudo-terminal API, which will provide a pseudo-terminal interface access to interactive programs. The API is aimed at developing an extension to the Unicon language to allow Unicon programs to easily utilize applications that require user interaction via a terminal. A pseudo-terminal is a pair of virtual devices that provide a bidirectional communication channel. This project was constructed to enable an enhancement to a collaborative virtual environment, because it will allow external tools such to be utilized within the same environment. In general the purpose of this API is to allow the UNICON runtime system to act as the user via the terminal which is provided by the API, the terminal is in turn connected to a client process such as a compiler, debugger, or an editor. It can also be viewed as a way for the UNICON environment to control and customize the input and output of external programs. Table of Contents: 1. Introduction 1.1 Pseudo Terminals 1.2 Other Terminals 1.3 Relation To Other Pseudo Terminal Applications. 2. Methodology 2.1 Pseudo Terminal API Function Description 3. Results 3.1 UNIX Implementation 3.2 Windows Implementation 4. Conclusion 5. Recommendations 6. References Acknowledgments I would like to thank my advisor, Dr. Clinton Jeffery, for his support, patience and understanding. Dr. Jeffery has always been prompt in delivering and sharing his knowledge and in providing his assistance.
    [Show full text]
  • Operating System Support for Parallel Processes
    Operating System Support for Parallel Processes Barret Rhoden Electrical Engineering and Computer Sciences University of California at Berkeley Technical Report No. UCB/EECS-2014-223 http://www.eecs.berkeley.edu/Pubs/TechRpts/2014/EECS-2014-223.html December 18, 2014 Copyright © 2014, by the author(s). All rights reserved. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission. Operating System Support for Parallel Processes by Barret Joseph Rhoden A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Computer Science in the Graduate Division of the University of California, Berkeley Committee in charge: Professor Eric Brewer, Chair Professor Krste Asanovi´c Professor David Culler Professor John Chuang Fall 2014 Operating System Support for Parallel Processes Copyright 2014 by Barret Joseph Rhoden 1 Abstract Operating System Support for Parallel Processes by Barret Joseph Rhoden Doctor of Philosophy in Computer Science University of California, Berkeley Professor Eric Brewer, Chair High-performance, parallel programs want uninterrupted access to physical resources. This characterization is true not only for traditional scientific computing, but also for high- priority data center applications that run on parallel processors. These applications require high, predictable performance and low latency, and they are important enough to warrant engineering effort at all levels of the software stack.
    [Show full text]
  • Ti® Macintosh® SE/30
    n 11acll1tosh®SE/30 Owner's Guide - ti®Macintosh ®SE /30 Owner's Guide - - - - - - ti APPLE COMPUTER, INC. This manual and lhe software described in it are copyrighted, with all rights reserved. Under the copyright laws, lhis manual or the software may not be copied, in whole or part, without written consent of Apple, except in lhe normal use of the software or to make a backup copy of the software. The same proprietary and copyright notices must be affLxed to any permitted copies as were affiXed to the original. This exception does not allow copies to be made for others, whether or not sold, but all of the material purchased (with all backup copies) may be sold, given, or loaned to another person. Under the law, copying includes translating into another language or format. You may use the software on any computer owned by you, but extra copies cannot be made for this purpose. © Apple Computer, Inc., 1988 Linotronic is a registered trademark of 20525 Mariani Avenue Linotype Co. Cupertino, CA 95014 (408) 996-1010 Microsoft and MS-DOS are registered trademarks of Microsoft Corporation. Apple, the Apple logo, AppleCare, NuBus is a trademark of Texas Applelink, AppleTalk. A/UX, Instruments. HyperCard , Im:~geW rit e r , LaserWriter, MacApp, Macintosh, OS/2 is a trademark of International and SANE arc registered trademarks Business Machines Corporation. of Apple Computer, Inc. POSTSCRI PT is a registered trademark, APDA, AppleCD SC, Apple Desktop and Illustrator is a trademark, of Bus, AppleFax, EtherTalk, FDHD, Adobe Systems Incorporated. Finder, LocalTalk, and MPW are UNIX is a registered trademark of trademarks of Apple Computer, Inc.
    [Show full text]
  • Openextensions POSIX Conformance Document
    z/VM Version 7 Release 1 OpenExtensions POSIX Conformance Document IBM GC24-6298-00 Note: Before you use this information and the product it supports, read the information in “Notices” on page 73. This edition applies to version 7, release 1, modification 0 of IBM z/VM (product number 5741-A09) and to all subsequent releases and modifications until otherwise indicated in new editions. Last updated: 2018-09-12 © Copyright International Business Machines Corporation 1993, 2018. US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Contents List of Tables........................................................................................................ ix About This Document............................................................................................xi Intended Audience......................................................................................................................................xi Conventions Used in This Document.......................................................................................................... xi Where to Find More Information.................................................................................................................xi Links to Other Documents and Websites.............................................................................................. xi How to Send Your Comments to IBM....................................................................xiii Summary of Changes for z/VM
    [Show full text]
  • A Machine-Independent DMA Framework for Netbsd
    AMachine-Independent DMA Framework for NetBSD Jason R. Thorpe1 Numerical Aerospace Simulation Facility NASA Ames Research Center Abstract 1.1. Host platform details One of the challenges in implementing a portable In the example platforms listed above,there are at kernel is finding good abstractions for semantically- least three different mechanisms used to perform DMA. similar operations which often have very machine- The first is used by the i386 platform. This mechanism dependent implementations. This is especially impor- can be described as "what you see is what you get": the tant on modern machines which share common archi- address that the device uses to perform the DMA trans- tectural features, e.g. the PCI bus. fer is the same address that the host CPU uses to access This paper describes whyamachine-independent the memory location in question. DMA mapping abstraction is needed, the design consid- DMA address Host address erations for such an abstraction, and the implementation of this abstraction in the NetBSD/alpha and NetBSD/i386 kernels. 1. Introduction NetBSD is a portable, modern UNIX-likeoperat- ing system which currently runs on eighteen platforms covering nine processor architectures. Some of these platforms, including the Alpha and i3862,share the PCI busasacommon architectural feature. In order to share device drivers for PCI devices between different platforms, abstractions that hide the details of bus access must be invented. The details that must be hid- den can be broken down into twoclasses: CPU access Figure 1 - WYSIWYG DMA to devices on the bus (bus_space)and device access to host memory (bus_dma). Here we will discuss the lat- The second mechanism, employed by the Alpha, ter; bus_space is a complicated topic in and of itself, is very similar to the first; the address the host CPU and is beyond the scope of this paper.
    [Show full text]
  • Systemprogrammierung Grundlage Von Betriebssystemen
    Systemprogrammierung Grundlage von Betriebssystemen Sachwortverzeichnis c Wolfgang Schr¨oder-Preikschat 27. Januar 2017 Die in der Vorlesung (mundlich¨ oder schriftlich) verwendeten Akronyme und Sachworte sind in der nachfolgenden Aufz¨ahlung zusammengefasst. Dabei werden die Akronyme nach den Sachwor- ten, fur¨ die sie die Verkurzung¨ bilden, aufgeschlusselt.¨ Fur¨ englischsprachige Sachw¨orter werden, soweit bekannt, die deutschsprachigen Entsprechungen angegeben. In der Beschreibung durch das "-Zeichen angefuhrte¨ Sachw¨orter zeigen einen Kreuzverweis an. Jedes Sachwort wird erkl¨art, wo- bei dies im Zusammenhang mit dem hier relevanten Kontext der "Systemprogrammierung und in Bezug auf Betriebssysteme geschieht. Die Formulierungen erheben nicht den Anspruch auf Gultigkeit¨ auch fur¨ andere Fachrichtungen in der Informatik. Ebenso erhebt die Aufz¨ahlung nicht den Anspruch auf Vollst¨andigkeit fur¨ das in der Vorlesung behandelte Fachgebiet. Der vorliegende Text ist ein Nachschlagewerk, dessen Lekture,¨ im Gegensatz zu einem Lehr- buch mit durchgehendem roten Faden, fur¨ gew¨ohnlich nicht von vorne nach hinten empfohlen ist. Vielmehr ist der Text Begleitmaterial zu den Vorlesungsfolien. Neben Systemprogrammierung sind hier insbesondere die Lehrveranstaltungen Betriebssysteme, Betriebssystemtechnik, Nebenl¨aufige Systeme und Echtzeitsysteme eingeschlossen. Daruber¨ hinaus kommen aber auch Lehrveranstal- tungen zu den Themen Rechnerorganisation und Rechnerarchitektur als Bezugspunkt in Frage. Viele der dort (mundlich¨ oder schriftlich)
    [Show full text]
  • Computer Architectures an Overview
    Computer Architectures An Overview PDF generated using the open source mwlib toolkit. See http://code.pediapress.com/ for more information. PDF generated at: Sat, 25 Feb 2012 22:35:32 UTC Contents Articles Microarchitecture 1 x86 7 PowerPC 23 IBM POWER 33 MIPS architecture 39 SPARC 57 ARM architecture 65 DEC Alpha 80 AlphaStation 92 AlphaServer 95 Very long instruction word 103 Instruction-level parallelism 107 Explicitly parallel instruction computing 108 References Article Sources and Contributors 111 Image Sources, Licenses and Contributors 113 Article Licenses License 114 Microarchitecture 1 Microarchitecture In computer engineering, microarchitecture (sometimes abbreviated to µarch or uarch), also called computer organization, is the way a given instruction set architecture (ISA) is implemented on a processor. A given ISA may be implemented with different microarchitectures.[1] Implementations might vary due to different goals of a given design or due to shifts in technology.[2] Computer architecture is the combination of microarchitecture and instruction set design. Relation to instruction set architecture The ISA is roughly the same as the programming model of a processor as seen by an assembly language programmer or compiler writer. The ISA includes the execution model, processor registers, address and data formats among other things. The Intel Core microarchitecture microarchitecture includes the constituent parts of the processor and how these interconnect and interoperate to implement the ISA. The microarchitecture of a machine is usually represented as (more or less detailed) diagrams that describe the interconnections of the various microarchitectural elements of the machine, which may be everything from single gates and registers, to complete arithmetic logic units (ALU)s and even larger elements.
    [Show full text]
  • EFM) for Greater Storage Density, and Cross-Interleave Reed-Solomon Code (CIRS) for Error Correction
    OpticalOptical StorageStorage TechnologyTechnology The Compact Disc HistoryHistory ofof thethe CompactCompact DiscDisc CD-V 光碟片 Video CD DVD-RAM 000000100001000000010000000000100004.7GB DVD A-E CD-MO Land Pit Land Pit Land CD-ROM 接物鏡 瞄準鏡 雷射二極體 光柵 CD-R DVD-RAM 2.6GB CD-I CD-RW CD-DA 偏光板 Photo CD 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 FamilyFamily ofof thethe CompactCompact DiscDisc Compact Disc Family CD-Audio CD-ROM CD-Recordable (Red Book) (Yellow Book) (Orange Book) CD-i CD-ROM XA CD-MO CD-WO CD-RW (Green Book) (Yellow Book) (Part I) (Part II) (Part III) MODE 2 CD-i Bridge Enhanced Music CD (Blue Book) Video CD Photo CD (White Book) CompactCompact DiscDisc OverviewOverview z An audio disc stores a stereo signal comprised of two 16- bit data words sampled at 44.1 KHz; thus 1.41 million bits per second of audio data are output from the player. z Error correction, synchronization, and modulation are required, which triple the number of bits stored on a disc. z The channel bit rate, the rate at which data is read from the disc, is 4.3218 Mbps. z A disc containing an hour of music holds about 15.5 billion channel bits. z Apart from modulation and error correction overhead, a CD-DA disc holds a maximum of 6.3 billion bits, or 783 million bytes of user information. CompactCompact DiscDisc OverviewOverview z Information is contained in pits impressed into the disc’s plastic substrate. 00000100010000000100000000010000 Land Pit Land Pit Land CompactCompact DiscDisc OverviewOverview z Pits are encoded with eight-to-fourteen modulation (EFM) for greater storage density, and Cross-Interleave Reed-Solomon code (CIRS) for error correction.
    [Show full text]