APPENDIX I CD-ROM Technical Information(1)

CONTENTS

Equipment---------------------     I--1
Software----------------------     I--1
Converting to ASCII Files-----     I--2
Directory and Index Information    I--2
Technical Documentation-------     I--3

EQUIPMENT

The two basic pieces of equipment needed to use CD-ROM's are a
microcomputer and a CD-ROM drive.  A printer is very useful but not
essential.  Your microcomputer should be equipped with at least 640K random
access memory (RAM).  While a hard disk is not required on your
microcomputer, it is very useful. 
 
SOFTWARE

Software is needed for accessing the CD-ROM as well as for accessing the
data. 

MS-DOS 3. 1 or higher is needed as your operating system if you have a CD-
ROM reader.  You will also need DOS file manager software such as
Microsoft's CD-ROM Extensions.  CD-ROM extensions is a collection of
programs that enables the microcomputer to communicate with the attached
CD-ROM drives.  You must have version 2. 0 or higher of the Microsoft Extensions. 

If you already have a CD-ROM drive, you may not know whether it is
equipped with file manager software like the CD-ROM extensions.  To find
out, try signing on to your CD-ROM drive just as though it is a magnetic
disk drive, and perform simple file management tasks, like listing the
directory.  (For example, from the DOS prompt, type the command DIR and the
letter used to designate the CD-ROM drive followed by a colon [e. g. , C>DIR L:] and press enter. ) If you get an error message, it may mean that 
you need to obtain and install CD-ROM extensions. 
 
CD-ROM Extensions

Although all versions of CD-ROM extensions work basically the same way,
installation procedures may vary slightly from one supplier to another. 
Many versions contain a program that will automatically install the
software for you, after you have answered a few questions about the type of
equipment that you plan to use.  Be sure to follow the instructions for
installing CD-ROM Extensions that are provided with the software. 

The first step, if you are installing extensions without the aid of an
automatic set-up program, is usually installing the device driver program
and MSCDEX. EXE on your bootable disk.  For computers containing a hard
drive, this usually means drive C.  The name of the device driver program
varies from one version of extensions to another; one common practice of
software developers is to name it after the brand of CD-ROM drive that it
supports, e. g. , HITACHI. SYS.  The device driver program and MSCDEX are
frequently set up in separate subdirectories; however, this practice is not
universal. 

The next step is to add a line to the CONFIG. SYS file to identify the
device driver program.  This line typically looks something like this:

DEVICE=\path\driver name/D:\driver alias/N:#

For example: device=\dev\HITACHI. SYS/D:MSCD001/N:1

The driver name (e. g. , HITACHI. SYS) and the driver alias should be
provided by the set-up program or in the instructions that accompany the
floppy disk containing the extensions software.  The symbol # at the end of
the line should be replaced with the number of CD-ROM drives (up to 4) that
will be hooked up to the microcomputer. 

The third step is to add a line to the AUTOEXEC. BAT file for running
MSCDEX. EXE and assigning a letter to your CD-ROM drive.  Depending on your
system configuration you may opt to set up one or more batch files to
accomplish the same purpose.  If you add a line to the AUTOEXEC. BAT file,
it will probably look something like this:

\path\MSCDEX. EXE/D:driver alias/M:8/L:L

For example: \BIN\MSCDEX. EXE/D:MSCD001/M:12/L:L


_____
(1)Portions of this appendix are adapted from Administrative Notes, the
Newsletter of  the  Federal  Depository  Library  Program
(May 22, 1989). 
 
The driver alias, which is really the name that your system will use to
identify the device driver, should be the same one that is named in your
CONFIG. SYS file. 

The number following M: is the number of memory buffers allocated
(usually 8, but sometimes more).  The last letter, following the L:;
designates the letter assigned to the CD-ROM drive. 

Though the final step is simple, it's also easy to overlook.  You must
reboot the system in order to activate the changes that you've made to your
CONFIG. SYS and AUTOEXEC. BAT. 

Once properly installed, the device behaves much like a read-only floppy
diskette drive, and simple MS-DOS commands such as DIR are possible.  If
the computer reports that the CD-ROM is ``not High Sierra,'' you must first
upgrade your Microsoft CD-ROM Extensions software to version 2. 0 or later. 
 
Data Retrieval Software

This CD-ROM contains data retrieval software.  This software was
developed and tested on a COMPAQ Deskpro 286 with 640K RAM operating under
MS-DOS 3. 31.  The software was compiled with Clipper (Summer '87).  There
are no special display requirements.  Please note that the retrieval
software will only run on IBM-compatibles operating under MS-DOS. 

To execute, type GO at the DOS prompt and ENTER. 

  Example: L:\>go

The data on the CD-ROM are in dBase III+TM format.  Data in dBase III+
format are recognized by many software packages including dBase IV TM,
Foxbase TM, Clipper TM, Supercalc V TM, Quattro Pro TM, and VP-Planner TM. 

Users of other types of systems, such as the Apple Macintosh, have access
to the files through support for ISO 9660 CD-ROMs. 
 
CONVERTING TO ASCII FILES

Users without database management software who wish to convert the files
to ASCII can follow the the code found in the README file on the CD-ROM. 

TECHNICAL DOCUMENTATION

The DOCUMENT directory on the CD-ROM contains sections of the Summary Tape
File 1 technical documentation in a series of ASCII text files.  These are
as follows:

ROSTER_P.ASC    Roster Page
ACKNOW.ASC      Acknowledgments
CONTENTS.ASC    Contents
ABST_S3.ASC     Abstract
HOWTOUSE.ASC    How to Use the File
SUB_LOC.ASC     Subject Locator
LIST_TBL.ASC    List of Tables
TBL_OUT.ASC     Table Outlines
SUM_LEV.ASC     Summary Level Sequence Chart
USERNOTE.ASC    User Notes Explanation and Notes
IDEN_FTN.ASC    Identification Section of the Data Dictionary
TBL_MTX.ASC     Table (Matrix) Section of the Data Dictionary
APPEND_A.ASC    Appendix A Area Classifications
APPEND_B.ASC    Appendix B Subject Characteristics
APPEND_C.ASC    Appendix C Accuracy of the Data
APPEND_D.ASC    Appendix D Procedures
APPEND_E.ASC    Appendix E Facsimiles of Instructions
APPEND_F.ASC    Appendix F Data Products and User Assistance
APPEND_G.ASC    Appendix G Maps (Text only)
APPEND_H.ASC    Appendix H Code Lists
APPEND_I.ASC    Appendix I CD-ROM Technical Information

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Figure 4. Reference Files
 
STF1STRU.DBF  This file describes the structure of the 67
              identification fields in the STF300 segment. This is in
              the format of a dBASE III extended structure which has been
              expanded to include brief field descriptions.
 
              Structure for database: stf300.dbf
              Number of data records:  67
 
              Field   Field Name     Type     Width  Dec

                1     FIELD_NAME   Character   10
                2     FIELD_TYPE   Character    1
                3     FIELD_LEN    Numeric      3
                4     FIELD_DEC    Numeric      3
                5     FIELD_TEXT   Character   60
           ** Total **                         78
 
TABLES.DBF    This file describes the numeric data tables.
 
              Structure for database: tables.dbf
              Number of data records:   4,756
 
              Field    Field Name     Type     Width  Dec
                1      TABLE        Character    6
                2      FIELD        Character   10
                3      TEXT         Character   68
                4      SEGMENT      Character    6
           ** Total **                          91
 
CNAMESss.DBF  This file contains a list of county names and FIPS
              county codes for State ss.
 
              Structure for database
 
              Field      Field Name     Type     Width  Dec
                1        CNTY         Character    3
                2        ANPSADPI     Character   66
           ** Total **                            91
 
\DOCUMENT Directory of technical documentation files in ASCII text
          format.

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Figure 5. Index Files
 
TABLES.NDX     This is a dBASE III index file for TABLES.DBF. The key 
                field is TABLE.
 
The following dBASE index files are for STF3??ss.DBF.
 
STF3AMss.NDX   The key fields are SUMLEV + CNTY + COUSUBFP + PLACEFP
                + TRACTBNA + BLCKGR.
 
STF1APss.NDX   The key fields are SUMLEV + PLACEFP.
 
STF3ATss.NDX   The key fields are SUMLEV + CNTY + TRACTBNA + BLCKGR.
 
STF3ALss.NDX   The key fields are SUMLEV + left(ANPSADPI,1).