Texas Instruments PHP1800 User manual

Texas Instruments

IMPORTANT
I«cord the ""rial number from the bottom of the Disk
DrIve ControUer and purchase date In the space below.
The ""rial number .. IdentUled by the words .'SERIAl.
NO." on
the bottom case. Always reference this
information In any correspondence.
_1100
pisk p,temo
rY
SV
stell1
IIodoI No.
lIIrIaI No. PureIII
.. Dale
Copyrighl: 01980rexulnslrumenl:alncorporated
Command Module program and dati base contents
copyright C1980 Texat Instruments IncotpOI'acecl.
See import ... warranty intormetion 81 baCk of bock.
Operatlng InstNctlons for the
. P~P1800 Disk Drive Controller,
the PHM3019 DIsk Manager COlIlmand Module,
and up to th,.. PHP1850 Disk Memoty Drives.

fABLE OF CONTENTS
Introduction. ....................... .. I
.I$'eatures of Your Disk System. ....... .. . _. . . . . . . . . .. 2
Diskette
Information __ _. .. 4
Write-protectingDfskettes ..........
.. 5
Labeling
and Handl1ng Precautions ... .. 5
sel-Up Insiructlons _........ .. 7
General Notes _ _. .. 8
Connecting the Controller ....... .............. .. 9
Connecting the Disk Drives _ .. . 10
Powering Up the System . . . . . . . II
A gulck Look althe Disk System . , 13
Disk
Manager Command Module Operation .. .17
Editing. ........................ .. . , 18
File
Commands 18
Disk Commands , •.... , , 20
Disk Tests .,................... . _ .. , 25
Single Disk Processing ..... .. . , . _ ..•........ 27
Disk System Operation with TI BASIC _ 28
Saving and Loading Prog:-ams ..... .. . 28
File Naming Conventions. . . . . , 29
File Processing. ........... .. . .. _ , 29
Cataloging Files ............. . _ 38
Sample Programs , , . . . . . . .. . 39
Appendix A: Error Codes in Tl BASIC 44
AppendIX 8: Error Codes In the Disk Manager Command Module 46
Appendix C: Diskette/Cassette Operations , 48
Transfer Programs between Cassettes and Diskettes , 48
Transfer Data from Cassette to Dlsk~tte .. ,'.' _ 48
se:vice and Warranty Information 50
In Case of Difficulty ................,........ 50
Diskette Failure Indicators . . . .. . 50
Exchange Centers (Local service Options) .............•. ,51
If You Have Questions or :'<Iced Assistance 51
Warranty 52
INTRODUCTION
The Texas Instruments Disk Memory System Is apowerful combination
of computer hardware and software that allows you to slOre and retrieve
data qUickly and accurately on 5-1/4 Inch diskettes (sold separately).
The system consists of the folloWing components:
DISK MEMORY DRIVE - The disk drive reads information
from
and wrlles Information on the diskette. It can rapidly
locate
any position or file on the diskette as dtre<:ted by the Disk
Drive Controller.
The disk drive spins the diskette at a ccnstant
speed and controls the movement of the magnetic head. You
may have one of two drives that have s!lghtly dUTerent
appearances. However. they function In exaclly the same way.
Diskettes (not included) are required.
DISK DRIVE CONTROLLER - The Disk DrIve Controller tells
the disk drive where to position the magnetic head in order to
read or write information properly. The controller also puts an
Index on the disk. mal<lng the data that has been written easy
to locate.
DISK MANAGER COMMAND MODULE -
The Disk Manager
SoUd
State Software
r•
Command Module helps you maintain
the Information on your diskettes. Naming and renaming
diskettes. renaming flies. deletong flies. copying Illes. and
copying diskettes all can easily be performed wllh the Disk
Manager
module plugged Into the computer console.
The Texas Instruments disk system represents a major advance over
other systems. Because the control software needed for Ihe disk system
Is In permanent ROM. In the Disk Manager Command Module. and In
the controller. the disk system uses arelatively small amount of
working space In the computer's available memory (RAM). The Disk
Manager Command Module proVides many advanced functions. For
instance. in copying a diskette It rearranges the flies on the diskette
alphabetically. And. If you Ilke. you can copy selected flies Instead of an
entire disketle. qUickly and easily. These and many other unique
features of the disk system are described In this manual
Get the most from your disk system b! first reading this manual and
performing Ihe examples as you go. Also review the appendices for
special information alld applications. Theil use the disk system with
your own applications.

Features of Your System
The most Important use of the disk system Is storage and retrieval of
Infonnatlon via TI BASIC programs. Through the proper BASIC
corrn'lland •. you can:
•SAVE PROGRAMS -
Each diskette holds over 720.000 bits of
information.
As an example. you can store about 100 BASIC
programs. each 50 lines long. on asingle diskette.
•STORE
AND RETRIEVE Dt\TA -You can store data that Is
accumulated when your programs are run. One disk can hold about
90.000 characters.
•UPDATE DATA -You can. through aBASIC program. update 'the
information In
your flies so that they contain the latest. most
accurate data. f
The Disk Manager Command Module can also be used to maIntain
Infonnatlon about the diskettes. such as the name of the diskette and
the names of the flies. Using the Disk Manager module you can:
•INITIALIZE DISKETTES -You
can prepare diskettes for use by the
system. The Initialization roullne proVides the diskette with header
infonnatlon for each sector. Each diskette must be Inlttalized before
initial use.
• NAME DISKETTES - Each diskette Is given lls own name. so that
the computer can verify that the proper diskette Is In place.
•RENAME. DELETE. AND COPY FILES -
These functions. of course.
can be perfonned via TI BASIC; however. the Disk Manager
Command Module helps you qUickly and easily rename flies. delete
files. and make ccples of flies.
•
MODIFY PROTECTION - You may want a Ole prolecled so that It
cannot be accidentally erased or changed. You can use the Disk
Manager Command Module to protect lies and. when you want to
change them. to release them from protection.
•COPY DISKETTES -
Diskettes and your disk system are avery
reliable
storage medium. However. under certain circumstances. the
data stored on a diskette can be totally or partially lost. For Instance.
If electrical power falls while the disk drive is writing on adiskette.
some data could be lost. To protect your data. It is customary to
make backup diskettes. The Disk Manager module makes It easy to
copy diskettes for backup even If you have only one disk drive.
•PERFOR\l TESTS - To ensure that the disk system Is operating
correctly. the DIsk Manager Command Module offers two different
tests. The first
checks several general areas 10 see that things are as
they should be. The second Is an exhaustive test. At the end of the
tests. all data on the diskette may have been removed. Before you
make adestructive test. you should make a backup copy of the
diskette so that your data ~otlost.
Certain other Command Modules also operate wllh the disk system to
save and read your mes more quickly than with cassettes or other
storage media. See the manuals for each module for further
Infonnatlon.

DISKETTE JlIIFORJlATION
Your disk system requires 5·1/4 Inch. slngle·sided. slngte-density. soft·
sectored diskettes. These diskettes are constructed of a highly fiexlble
plasll'c OIm. coated with a thin layer or Iron oxide which can be
magnetized In very sma\J areas without affecting surrounding areas.
The computer Interprets these areas ri magnetization 88 coded
Information.
Note: Adl8kette comes In aprotective jacket. inside a storage envelope.
For
best results. keep the diskette In the storage envelope except while
using. Never remove the diskette from Its protective jacket.
Each diskette Is divided Into tracks. which are 40 (on some diskettes
only 35) concentrtc circles. The tracks are numbered from 0 to 39 (or
34~ starling at the outside track. Each track. In turn. Is d1vlded Into
nine sectors. There are thus 360 (or 315) sectors. each of which can
contain up to 256 bytes of information. or 2048 tiny magnetized areas.
The sectors are numbered 0 through 359 (or 3141. starUng with sector
of the first track and going to sector 8 on the last track. Each sector has
additional space used only by the controller to verify sector
Idenllflcatlon and data accuracy.
The disk controller uses sectors 0 and 1 to form an Index of Ole
locations. If those sectors become damaged and unreadable. the
computer cannot locate any Illes on the diskette. and the contents of the
enUre diskette will be unusable.
To use your disk drive system. Insert the proper diskette. and use Tl
BASIC or a Command Module designed to operate with the disk system.
The work of keeping track of your OIes and reading from or writing on
the proper place on !he disk Is taken care of by the system.
Diskettes can be named for reference purposes. The name of a diskette
can be up to ten characters long and may use any characters except the
period and the space character. Valid names for diskettes Include
DlSK21 MYDISK MY_DISK
PRK-DATA
TlRlL.DATA GEORGE BACK-UP BU03l24/80
The following are not valld diskette names.
3.1416 MY DISK THISNAMEISTOOLONG
Write-Protecting Diskettes
Diskettes have a notch In the edge ofthetr protective container. As long
as the notch ts left open. the drive functions normally. Covering the
notch wlth apiece of spectai tape provided with the dtakette prevents
wrtting on the diskette. When you have a diskette containing programs
or data that you want to protect. cover the wrtte·protect notch. Then
the Information cannot be accidentally written over. If you want to
write
on the dtsk later. the lape can be removed.
o
WR~P.fc9JTECT og
"J
1
00
Labeling and Handling Precautions
In handllng diskettes. be very careful not to touch the diskette Itself.
Handle it genlly by Its protective cover.
Do not write on the protective jacket wlth apencil or ballpoint pen since
these could damage the diskette. Use a marker pen and Ught pressure
or write what you wish on a label and then put the label on the
protectiveJacket. Adhesive labels are avallable from many sowces.
Any magnet or magnetic field can afiect data on adiskette. Do not
bong any magnet near a diskette. and do not put a diskette near or on
top of anything that generates a magnetic field. such 88 a' television. a
monitor. a speaker. etc. Also be aware of more ob8cure magnetic
sources. such as magnetic cabinet latches. magnets In children's toys.
and magnetic note holders. As a general rule. do not store diskettes
within three feet of any magnellc source.

The magnetic head that reads and writes Infonnallon on the diskette
touches the diskette's surface during operation, If dust or lint is on the
surface, It may be ground Into the dlskette's surface. scratching It. For
best """ults, keep the door on the front of each disk drive closed except
when inserting or removing a diskette.
CAUTION
Never put a diskette in the drive until the controller
and dtsk drive are properly connected and power Is
turned on to all units. Also. never imert or remove
dtskettes ... hen the drive light Is on. And never have
a dIskette In the drlve when removing the cable.
Diskettes should always be stored In their protective
jackets.
To Insert a dtskette In the disk drive. first open the disk drive door on
the front of the unit. Hold the diskette gently by the comer nearest the
write-protect notch. and Inselt It Into the drive with the notch to the
left. Close the door carefully.
11-
.....
To remove the diskette. open the dtsk drive door, and extract the
diskette. Store It In lis storage envelope.
8n-up 11'I8TRUCTIONS
Carefully unpack the Disk Memory Drive and Its cable. The disk drive Is
a precision devIce which uses moving parts with exacUng tolerances. so
handle It carefully, Save the packing materials and carlons so that you
can safely transport the unit later.
The drive as it comes from the factory Is ready to run as the only drive
on your system. If you are using more than one drive. the followIng
process must be done to all but one of the drtves that you are using.
The last drive should be connected without being alteled.
DO THE FOLLOWlNG ONLY IF YOU
ARE USING TWO Oil THREE DRIVESI
1. WARNING: ALL POWER CORDS MUST BE DISCONNECTED
FROM THE POWER OUTLETS DURING THE FOLLOWING
PROCEDUREI
2. On all but one of your drives. use aPhillips head screwdriver to
remove the six screws that hold the cover. Lift the cover off.
3. Locate the main printed circuit board. On Lt. locate the termination
resistor pack. It has 14 leads and looks I1ke an integrated clreul.!.
(The maln boards look slightly dlJferent on,the two dtfferent kinds of
drives. out the pack Is In the same place on each,) Be careful not to
disturb the strapping pack (which 1s,a1SO removable) located very
near the reslstol pack.
RESISTOR PACK
4. Remove the tennlnallon resistor pack by prying each end up sl1ghtly
with a small screwdriver and then Ilfllng it out by your thumb and
forefinger. Pull straight up.

CONSOlE AND CONTROLLER
•
-
•C
CL:::::C >OOClOC>
o=r
iCCCO ue
,=D+
-_ .. _.
Connectlng the Controller
I. Tum off the computer console and all allached devices.
2.
The console connector on the controller projects from the left side of
the unit. Place the unit so that Its connector is to the right d and
parallel to the computer console.
3. A small sliding door protects the accessory connector on th. right
side of your computer. Carefully slide this door upward so that the
connector is visible.
4. Make sure the console and the controller are parallel. with the
connectors aligned. Then hold th. console firmly with your left hand
and gently push the controller connector onto the console connector.
+
=
Ic c CClCl CXXJC:X:)
oooc
OC>OO,
5. Save the single drive termination resistor pack so that you can
reinserl It if the drive is e"er to be used as a single or last disk drive.
Note
that if the socket for the resistor pack has more holes than
tJ1ere ..... pins on the pack. Install the pack toward the outer edge of
the circuit board. leaving the unused holes toward the center of the
board.
6. Reattach the cover on the drive. aligning and tightening the screws
carefully. DO NOT OPERATE ANY UNITS WITHOUT
REATTACHING THE COVER.
General Notes
The drives should be located conveniently so that you can insert and
remove diskettes. The drives should be placed horizontally. Stacking of
disk drives Increases Internal temperatures and may adversely affect
the diskettes.
Disk drives and diskettes are affected by static electricity. magnetic
fields. and dust. The drives should not be near the monitor screen. as it
generates apowerful magnetic field. If possible. the drives should be In
alow
humidity, dust-free environment. free from static electricity. If
static electrlclty is a problem In your area, treating your carpet with an
anti-static preparation may be helpful.
Seltlng up the controller and disk drives is a simple process. First.
connect them to the Home Computer, and then test their operation. The
steps Involved In both procedures are Included In this section.
Information
about connecting accessory devices Is also Included. Please
read this material completely before proceeding.
Note: No more than three accessories can be attached In series
to the accessory connector on the right side of the computer
console. If a Solid State Speech™ Synthesizer Is attached to the
computer, It must be connected to the console 11rst.
Other accessories, including the controller. can be connected in any
order after the speech unit.
CAUTION
The elecrronlc components of the controller and disk
drives can be damaged by static el",trlclty discharges.
To
avoid damage. do not touch the connect ...
contacts or expose them to static electricity.
CONSOLE, SPEECH SYNTHESIZER. AND CONTROLlER
Once you've unpacked the units and made any modifications necessary
to the disk drives. you're ready to connect the units to the Home

Camecting the Disk Drives
Each drive has an attached cable wttb two connecto1"ll. one at tbe end of
the cable and one near the mtddle of lIle cable. The connector on the
'-l
end goes tnto the port on the rear of the controller or. tn the case of
multiple dtsk drives. tnto the middle connecto, on the I'recedlng drive
unit. using the adapter board (see illustration below). Note: It may be
necessary'to rotate lIle connector in order to insert it. It goes in easily if
you have It positioned correctly.
If you have one drive. connect it to the controller. (Remove and save the
adapter board in the event a drive is added later.)
If you have more than one drive. connect them to the controller In
series. with all but the last one (the one farthest away from the
controller) modl/led as descrl:led above. Connect the ftrst drive to the
port on the rear of the controller. The connector on the end of the
second drlve's cable plugs tnto the adapler board In the mIddle of the
first drlve's cable. Tile third drive Is connected to the second drive In
the same way. Whether you have two or three drives. the drive farthest
away from the controller should be the one that has not been modified.
(Iii
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Powering Up the System
After the controller and drives have been connected. connect the power
to the disk controller. and tum II on with the switch on the front of the
unit. Now connect the power to the disk drives. and tum them on wllh
Ute swllch on the rear of each unit.
WARJfING
Eacb time yoa operate yoar compater/dilit
.,..tem. foUow lbl. power-ap oeqaeDce:
1. Fir.t tam OD the diu cODtroUer and 4l.1t
driyel.
2. TheD tUl'11 OD lbe compater cODoole aad
monitor.
for proper memory allocation by the computer.
the disk controller must be ON when the
mmputer Is switched on. Otherwise the disk
drives. controller. and Disk Manager module will
not function correctly. The computer must be
turned ofT and turned back on In order to
restore norma) operation.
When you turn on lIle console. the disk drive working lights may come
on briefly and then go off. II they stay on. the disk drive cable Is
probably plugged in upstde down. Tum ofT aU units and make sure that
Ute disk drlve cable connection(s) have been made properly.
Note: 11 you baye more tbaD ODe driye attacbed, they malt aU be
.,"tcbed on, eyeD If you plan to "" only ODe.
Do not put any diskettes In the drives yet. Go into Tl BASIC and enler
the following program.
100 OPEN.1 :"DSK1 X'
110 ClOSE.1
Run the progrann and observe Drive One IDSK I). Its "'Norklng" light
should come on as It attempts to read a diskette. The Jghtindlcales
thaI the drive Is connected properly. If the drive does something else. or
does nolhing. check aU connections and see that all devices have power .
DSKI DSK2 DSK3
The ft1"llt drive. the one connected directly to tile controller. Is identified
as DSKI by TI BASIC. The second drive. connected to the cable of
DSK I. is DSK2. The third drive is DSK3. The labels provided with your
drivels) can be used to Identify each drive.

Even though the disk drive is operating. the following message appears
on the screen because there Is no diskette In Ihe disk drive.
·VO ERROR 06 IN 1 (J()
Repeat the test for Drives Two and Three If you have them. altering the
program to reference DSK2 and DSK3. respectively.
Now
that you have verilled that the dIsk drives are operating. type BYE
and presll' ENTER. Then Insert the Disk Manager module (supplied wIth
the controUerllnto the slot on the console. Pressing any key mskes the
master selection Ust appear. You now have the option of utll1zlng your
disk system with Tl BASIC or with the Disk Manager Command Module
(In English. German. or French).
You are ready to start using your disk system as descrtbed In the
foRowlng sections of this manual. If you have problems in operating the
disk system. please revIew the Service and WWTanly section
thoroughly before returning any unIts for repair.
AQUICK LOOK AT THE DISK SYSTEM
This section describes how you can use the system to Initialize a
clskette. write a program. save It on the diskette. run the program to
write and read Information from the diskette. and see the calalog of
what Is on the diskette.
Make sure that power Is supplied to all devices. Tum on the
disk system. monitor. and computer. Insert a new diskette In
DrIve
One IOOKl). Plug the Disk Manager Command Module
Into the computer.
Press any key to proceed. Then press 3to select the Disk
Manager Command Module. After a brief title sequence. the
following screen appears.
DISK MANAGER
1FIlE COMMANDS
2 DISK COMMANDS
3 D6K TESTS
4 SET ALL COMMANDS FOR
SINGLE DISK PFDCESSING
YOUR DiOCFI 1
The number I and the CUl'llOr (a small rectangle) alternately flash tn the
space following the YOUR CHOICE? prompt. Number 1 Is the default
option. However.
you want option 4 because only DrI,e One Is going to
be used at this time. Chooslng this option speeds up the processes.
Enter It by pressing the 4key and pressing ENTER. The screen changes
so that what was option 4now says SINGLE DISK PROCESSING HAS
BEEN INITIALIZED.
To
select the second option. Disk Commands. press 2 and then press
ENTER. The following screen appears.
DISI< COMMANDS
1 CATAlOG DISK
2 BACKUP DISK
3 MOOFY DISK NAME
4 INTIAUZE NEW OISK
YOIJl DiOICE? 1

Again option number 1 Is the preselected default. However. every new
diskette must be initialized 110 that the computer can use tt. Inltla1lze
t~e diskette by pressing 4 and then pressing ENTER. The following
sc~c;en appears.
INlllAUZE I'eN D6l<
MASTER DISK [1-3]1 1
DISK NOT INITlALIZED
NEW llISKNAME? _
The prompt MASTER DISK (I -3)? has been answered as I because
single disk operatloo has been Initialized. You can answer the prompt
Ne:W D1SKNAME? as you lite. Legal diskette names are up to ten
characters long. and they cannot contain aperiod or a blank. Type the
name you wtsh and press ENTER.
The prompt 40 TRACKS (YIN)? appears next. Your answer depends on
the brand or type of diskette you are using. (Most have 40 tracks. but a
few only allow 35. When you purchase adiskette. ask your dealer how
many tracks tt holds.) If you enter YES by typing Y and then pressing
ENTER (or Just pressing ENTER to confirm the y that Is already there), the
diskette Is Initialized for 40 tracks. If you enter NO by typing N and then
pressing ENTER. the diskette Is Initialized for 35 tracks.
Tbe message SCREEN IS COMPLETE PRESS: PROC'D, REDO. BEGIN.
OR BACK appears. If the screen Is not right. press SHIFT R (REDO) and
reenter the correct responses. When the screen is correct. press SHIFT V
(PROC'D), The diskette Is now initialized, a process that takes atotal of
about a minute. The message
INIT1AUZE NEW DISK
WORKING .... PLEASE WM
Is on the screen for a moment. Then the message 0<WORKING....
PLEASE WAIT
appears, followed by 1<, and then 2>. The number 2 Is
increased by one as each sector Is Initialized, ending at 359 (or 314).
After
the initialization process, the message
0Sl<1 - DlSKNAME - diS<name
AVAJLABlE- 358 USEO- 0
appears If all seclors 'are usable. Each seclor that Is unusable Increases
the USED
number by one and decreases the AVAILABLE number by
one. Now, bold down the SHFT key and press W(BEGIN) to return to
the maln DIsk Manager selectlon list. Then press SHIFT Z (BACK). When
the
master computer title !!Creen appears. select TI BASIC and enter the
following program.
100 OPEN .1 :"0Sl<1.FlRSTALE".FEl.ATM.INTERNAL
110FOAA-1 TO 20
120 PAINT .1 :"THIS IS IH:OR)";A
130 NEXT A
140 INPUT "WHlCH AECOAO? ":A
150 IF A<1 THEN 200
160 IF A>2O THEN 200
1 70 INPUT '1.AfC A -1 :M.B
1 BO PAINT M;B
190GOTO 140
200 ClOSE .1
To save the program on the diskette in Disk Drtve One under the name
"PROGRAMI". enter SAVE DSKl.PROGRAMI. The disk drive
"working" light goes on, the diskette spins. and the program Is saved
on the diskette. Enter NEW to remove the program from the computer's
memory. e:nter OLD DSKl.PROGRAMl. The program Is loaded Into the
computer's memory from Disk Drive One. Enter J,JST to see tbe
program.
Enter RUN to run the program. The disk drive "working" light comes
on as twenty items are stored. The prompt WHICH RECORD? appears.
Enter a number from Ito 20. That record Is retrteved and displayed on
the screen. You
can retrieve the records In any order. as often as you
Ilke.
When you are finished, enler 21. The file is closed and you are back In
TI BASIC. Enter BYE (not SHIFT OJ t, leave BASIC to ensure that the file
is properly closed and no data Is lost.
With
the masler selection list on the screen, selecl the option lor the
Disk Manager Command M¢ule. Set the commands for single disk
processing as you did before. Again choose option 2. DISK COMMANDS.
This lime choose option I, CATALOG DISK. The following screen
appears.
CATALOG OSK
MASTER DISK [1-3]1 1
OISI<NAME - ciskname
WHERE 00 YCU WANT USTING?
1 SCREEN
2 SOLD STATE PRINTER
3 R5232 NTERFACE
401HER
YOUR a-tOlCE'? 1

The first prompt, MASTER DISK (I·3)? has already been answered as I
because single disk operation has been Initialized. You want the catalog
on the screen, so press ENTER to confirm that choice. The following
apJlPlTS.
SCREEN IS COMPLETE
PRESS PROC·D. REDO.
ElEGIII, OR BACK
Press SHIFT V(PROC'D) and the follOwing screen appears.
0SK1 -DlSKIII'\ME -disk"""'"
AVAJLAaE- 348 USED- 10
Rl..ENI\ME SIZE TYPE P
ARSlfILE aINT/AX BO
PROGRAM1 2 PROGRAM
WORKING...... PL.EASE WMT.
PRESS
CLEAR TO ABORT COMMAND
After the screen has been ftlled with all the lnformatlon, the bottom
message 15 replaced with
COMMAND CDIllPLETED
PRESS: PROC'C. REDO,
BEGIN, DR BACK
On the catalog, the D1SKNAME 15 the name you gave to the diskette.
The 348 after AVAILABLE Is the number of sectors not used. The 10
after USED 15 the number 01 sectors in use. The Inforrnatlon below
shows that FIRSTFlLE Is an Internal ftle with afixed length of 80 bytes
taking up 8 sectors and PROGRAM I is a program me taking up 2
sectors. Since there Is nothing under "P," neither of the Illes is
protected from being written over.
To leave the Command Module, press SHIFT \Ill (BEGIN} and then SHIFT Z
(B!\CK).
That completes the qUick look at the disk system. The next sectlons
describe In detail all of the capabUttles of the Disk Memory System,
DIS& MANAGER COIlllAND IIODULE OPERATION
The Disk Manager Command Module is used to perform operations that
are impossible or Inconvenient in TI BASIC. The module lets you store,
retrieve. or manage ftles by choosing optlons and giving ans_rs to
prompts on the display screen.
When you have completed all the inputs required on adisplay, the
message
PRESS: PRDCD, REDO.
BEGIN. OR BACK
appears. You can lhen choose what you would like to do.
•PROC'D -
Pressing SHIFT V(PROC'D) causes the computer to
perform
the action that was requested or to repeat the current
process.
•REDO - Pressing SHIFT R(REDOI enables you to start again at the
top of the current display. This lets you make changes in the answers
to your prompts.
•BEGIN - Pressing SHIFT W(BEGIN) takes you back to the nuUn Disk
Manager selection list.
•BACK -
Pressing SHIFT Z (BACK} takes you back to the previous
index (selection list).
(Note: These options are always active when the cursor appears on the
!!Creen.)
Some prompts already have an answer In place. These preprogrammcd
responses (default vaLues) represeni common or usual answers to these'
prompts. If the answer 15 the one you want. you don't need to type that
response. Just press ENTER to confirm it. If you want to give adlfTerent
response, press the key for the response you want and then press
ENTER.
IIIPORT ANT NOTICE
To leave the Disk Manager Command Module without
the chance of losing any programs or data slored on
the diskette, follow this procedure:
I. Press SHIFT W(BEGIN) to return to the lniUal Disk
Manager selecUon Index.
2. Then press SHIFT Z (BACK) to leave the module,
closing all ftles.

Editing
If you want to correct a typtng error before you press ENTER. use the
editing and cursor-moving keys. Holding down the SHIFT key and
prti!lstng G. move the cursor left to the chamcter you want to change.
Retype the correct eharactensl_
You can ~rase erro,.. by using the Spactl Be,. Backspace (SHIFTG) to a
point where you want to begin erasing. Then press the Spece BI' to
move the cursor over the characters on the screen. You can also erase a
line (before pressing ENTER) by holding down the SHIFT key and
pressing C.
In certain applications. SHIFT F(DELETE) and SHIFT G(lNSERTI are also
active.
After you have pressed ENTER. you must press SHIFT R (REDO) to
change or correct entries.
File Commands
The first command on the main selection list of the Disk Manager
module is FILE COMMANDS. Choosing this option gives you access to
the commands that operate on Individual Illes rather than the entire
lisk.
The name of afile can be up to ten characters long and can use any
characters except the period and lhe space character. Valid names for
files are the same as valid names for diskettes.
When you choose the FILE COMMANDS option. the following screen
appears.
ALE COMMANDS
1 COPY FIlE
- 2 RENAME ALE
3 DELETE ALE
4 MODIFY ALE PROTECTION
YOLl'! CHOICE? 1
COPY FILE -You
can copy afile in TI BASIC by reading it and then
writing it. item by Item. to the new file. With the Command Module.
you can do the process more slmply_ When you choose this option, the
foHowlng screen appears.
COPY ALE
MASTER DISK [1-3J? 1
Your response to the prompt MASTER DISK (1-31? indicates which disk
drive coninins the file you are going to copy. When you answer the
prompt. the DISKNAME is filled in. and the prompt FILENAME?
appears. Enter the name of the file you wish to copy.
The prompt COPY DISK (1-3)? appears. Your answer determines which
disk dlive will be copied 10. When you answer it. the DISKNAME is
filled in. and the prompt FILENAME? appears. Enter the name of the
new file.
RENAME
FILE - When you choose this option. the following screen
appears.
RENAME FILE
MASTER DISK [1-3)? 1
Your response to the prompt MASTER DISK (1-3)? In,iicates which disk
drive contains the file you want to rename. When you answer, the
DlSKNAME is filled In. and the prompt FILENAME? appears. Enter the
present name of the fIle. The prompt NEW FILENAME? appears. Enter
the new name that you want the file to have.
DELETE PILE - With the Command Module. you ca" not only delete a
file.
but also go through ail the Illes on a diskette, choosing which ones
to delete. When you choose this oplton. the following screen appears.
DELETE FILE
SELECTIVE [YIN]? N
The answer to the prompt SELECTNE (Y/NI? determines whether you
delete JUs,_ one llIe or go through the diskette choosing which Illes to
delete. If you enter N. then you dele:e Just one file. If you enter Y. you
may select which files you wish to delete.
The prompt MASTER DISK (I-3)? appears. Your response indicates
which disk drive conltalns the filels) you are going to delete. Based on
your answer. the DISKNAME is filled in. If you have chosen not to be
selective, the prompt FILENAME? appears. Enter the name of the llIe
you wish to delete.

If you have chosen 10 be selective. eaeh me on the dlsketle Is presented
by name, and you choose whelher or not to delete II by answering lhe
prompt DELETE (YIN)? If a file Is protected. and you choose to delete It.
theprompt OVERRIDE PROTECTION (YIN)? appears. If you want to
delete
lhe file even though Ills marked as protected. enler Y. If you do
nol wish to delete It. enter N. The computer wtll return an error
message. but you can go on wllhout any difficulty by pressing SHI" V
(PROC'D).
MODIFY FILE PROTECTION - The Command Module enables you to
mark a me so that it cannot be written on. This means that aTl BASIC
program or data cannot be changed wllhout removing its protection
with
the Command Module. When you choose this opUon. lhe followIng
screen appears.
MODIFY RLE PROTECTION
MASTER DISK r·3]? 1
Your response Indicates whieh disk drive contains the file you want to
modify.
When you answer the prompt. the DlSKNAME Is filled In.
Then. enter the name of the rue you wish to alter. The anawer 10 lhe
prompt PROTECT (YIN)? determines if lhe me is to be protected from
being written on. If you answer Y. Ills protected. If you answer N. It Is
nol protected.
If afile is
protected. you cannot copy another rue over It or rename it
with lhe Command Module. Attempts to perform these operations will
cause an error message to appear. In TI BASIC. a protected data me
may only be opened for Input; It cannot be written to.
Disk Commands
The second option on the maln selection list of the Disk Manager
module Is DISK COMMANI;lS. Choosing this option gives you access to
the
commands that Involve lhe entire disk.
0lSK COMMANDS
1 CATALOG 0lSK
2EWXUP 0lSK
3 MOOFY 0lSK NAME
4 INITIAUZE NEW DISK
YOUR CHOICE? 1
CATALOG DISK - Choose this opllon to get acatalog of all the
programs and data files on lhe disk. When you choose It. the (ollowlng
screen appears.
CATALOG DISK
MASTER 0fSK (1-3J 1
Choose lhe disk drive conlainlng the diskette Ihat you want cataloged.
As soon a. you enter the disk drive number. the dlskette's name is
filled in.
and the follOWing appears. .
WHERE 00 YOU WANT LISTING?
1 SCREEN
2 SOUO STATE PAINTER
3RS232 INTERFACE
4 OTHER
YOUR CHOICE? 1
If you choose 1. SCREEN. the listing appears on the monitor screen. If
there are :00 many lines to fit on lhe screen. press and hold the SpIce
Bar unttlthe lines stop scrolling. (Press and hold the Space 8 .. once
more to s!art scrolling again.)
If you choose 2. SOLID STATE PRINTER. the entire catalog is printed
00 lhe Thermal Prlnler connected 10 the compuler.
If you choose 3. RS232 INTERFACE. the entire catalog is transferred to
lhe RS232 Interface with default parameters. From there 11 may go to a
line printer, through amodem. or to whatever device Is connected to
RS232 Interface. See the RS232 Interl'ace Manual for more Information
00 its use.
If you choose 4. OTHER. the prompt DEVICE NAME appears. You may
then choose any device and file that you could choose If you ""ere using
the TI BASIC command OPEN. For example. you could enter
DSKI.CATLIST. and the catalog woold he put on the diskette in Disk
Drive
One under the file name CATLIST.

The catalog Itst has the following fonn.
OSK 1 - DlSKNAME _diskname
AVALABLE- rm USfD- nm
ALEIIAME SIZE TYPE P
AAA~AAAAAA mn PROGRAM
_88888 non DIS,vAAnm Y
CCcccax:cC mn DISIAXnnn
DDDDDDODDD nm INT,vAAnnn Y
EEEEEEEEEE nnn INTiRXnnn
The characters after DlSKNAME are the name you gave the diskette.
The number shown after AVAILABLE is the number of sectors lhat are
a'laUable for use. The number shown after USED Is the number of
sectors that are being used to store data and programs plus the number
of sectors that are not usable. The used and available sectors total 358
(cr313).
The FILENAME is the name of the flIe. and SIZE Is the number of
sectors used for the file. TYPE gives the parameters of the file. If afile
type Is PROGRAM. the file Is probably aBASIC program. DlSIV ARnnn
indicates aDISPLAY format file of V!\RIABLE length records. with a
maximum record length of nnn characters. Afile Itsted as DlS/FIXnnn
Is aDISPLAY format file of FIXED lenglh records. with a maximum
record length of nnn characters. INTN ARnnn designates an INTERNAL
f<rmat file of VARIABLE length records. with a maximum record length
of nnn characters. whUe a flIe listed as INTlFlXnnn is an INTERNAL
f<rmat file of FIXED length records. with areoord length of nnn
characters. (See File Processing In Ihe next Stcllon of this manual for
an explanation of DISPLAY versus INTERNAL formats and VARIABLE
versus FIXED lengih files.) The "p" column Indicates whether or not
the file is protected. If a "Y" Is present. the file cannot be wrllten on.
BACKUP DISK -You choose
this option when you want to make a
copy
of adiskette. This Is usually done so that you have a spare copy of
data and programs In case something happens to the original. It Is also
used to put files In order on adisk. Making a backup copy compresses
the Informalion on the diskette to take as little space as possible. (To
copy
disks if you are using a single disk drive, follow the Instrucllons
given on tbe sereen.)
Note: How long the backup takes depends on two things; the number of
files
on the master diskette and the length of each file. Also. If the copy
diskette has not preViously been Initialized. the Initializing process wlll
require approXimately one additional minute. As a general rule. It takes
about 20 seconds to copy 11.5K byles of data
The following describes the backup process when you have two or three
drives. W'len
you choose this opllon. the following display appears.
BACKUP DISK
SELECTIVE (YIN)? N
Your
response to the prompt SELECTIVE (YIN)? dete,mlnes II all the
mes or only selected files on the dlskelle are to be coplcd. If you enter N.
all files on the diskette are copied. II you enter Y. you may choose which
files you want to copy_
The prompt MASTER DISK (1-3)? appears. requesting the number of
the disk clrtve containing the dlskelle thatls 10 be copied. When you
answer lhat prompt. the diskette's name Is nlled In.
The prompt COPY DISK (1·3)? appears. Your response here determines
which diskette will have the data copied onto It. If the diskette is
Initialized. its name Is filled In. If It Is not Initialized. the message DISK
NOT lNlTIALIZEDappears.
Then the prompllNITIALIZE NEW DISK
(YIN)? appears. Data cannot be copied unless the dIskelle Is initialized.
If the dlskelte Is Initialized and has data on It, the data there Is not
erased In the copy process.
If the sectors USED on the master diskette exceed the sectors
AVAILABLE on the copy dlskelle. there will not be enough room on the
copy diskette. If you have already started copying. press and hold SHIFT
C(CLEARI to stop the process. Then Inserl a new copy diskette and
start over.
If you choose to initialize the diskette. Ihe prompt DlSKNAME? appears.
Enter the name you want to use for the new diskette. Then the prompt
40 TRACKS (YIN)? appears. If the new dlskelte has 40 tracks. enter Y. If
It has 35 tracks. enter N. The message INITIALIZE NEW DISK
WORKING.....PLEASE WAIT
appears as the diskette Is Initialized.
After
the new diskette Is Initialized. or If It was already Initialized. the
copy process continues. If you are copying the entire diskette. the
message WORKING .....PLEASE WAIT PRESS: CLEAR TO ABORT
COMMAND appears. and Informalton about the copying process
appears on the screen as mes are copied.
Note: If you need to stop the process. you may have to press and hold
SHIFT C(CLEAR) for afew seconds. The DIsk Manager module wlll not
stop unW It finishes copying the current file. Hold down SHIFTC
(CLEAR) LnW
the module responds.

If you are copying only selected flies. each llle Is listed. followed by the
prompt COPY FILE (YIN)? You may choose to copy the file by entering
Yor not to copy It by entering N.
Ortll single disk drive sysiem. the copy procedure consists of reading as
much as possible from the first diskette into the computer's memory.
removing the first diskette and Inser.ing the second. writing the data
from the computers memory onto the second diskette. removing the
second diskette and reinserting the forst diskette as prompted. and
repeating the process until all data has been coplcd. The on-screen
prompts gUide you through the process.
MODIFY NAME - Choose this option when you want to change the
name of the diskette. When you choose It. the follOWing screen appears.
MODIFY DISK NAME
MASTER DlSK [1-3]? 1
Your response to the prompt MASTER DISK (1-3)7 Indicates the disk
drive that contains the diskette. The disk name Is then filled in and the
prompt NEW DISKNAME? appears. Enter the name you want the
diskette 10 have.
INITIALIZE NEW DISK - The first thing that has to be done to a new
diskette Is to Initialize II so that the computer can use it. When you
choose this option. Ihe follOWing screen appears.
INITIAU2E NEW DISK
MASTER DISK [1-3r 1
Your response to the prompt. MASTER DISK (1·3)? Indicates which disk
drive holds the diskette. Then the name of the diskette or the message
DISK NOT INITIALIZED appears. followed by the prompt NEW
DISKNAME? You
then type and enter whatever name you want to give
the disk. Legal disk names are up to len charactcrs. not containing a
period
or a blank.
The prompt 40 TRACKS (YIN)? appears. If the new diskette has 40
tracks. enter Y. If II has 35 tracks. enter N.
When you press SHIFT VlPROC·Dl. the diskette Is InltLallzed. a process
that takes about a minute. The message
INITIAJZE NEW DISK
WORt<ING .... PLEASE WAC
is on the screen for a moment. Then the message 0< WORKING....
PLEASE WAIT
appears followed by 1<. and then 2>. Thc number 2 is
Increased by one as each scctor Is InUallzcd. ending at 359 (or 314).
24
Disk Tests
The third option on the Disk Manager selection list Is DISK TI':STS. Ills
sometimes necessary to check the condition of a diskette. the disk
drive. and the controller. There are two levels of testing that can be
done. The first Is called aqUick test. Each loop takes about two minutes
if you choose to make the test destructive and about 40 seconds If you
choose to make tt non-destructive (Information on the disk Is
preserved).
The non-destructive test should satisfy most requirements.
The destructive version of the test should normally be done to new
diskettes to determine whether or not they are good.
The sccond test Is a comprehensive test thai runs an exhaustive check
on the diskette. controller. and disk drive. In the process. It destroys all
!he data lhai was on the diskette. Before running this test. you should
make a backup copy of the dtskette If you want to retain the data. or
you can run lhe test on a blank diskette. The comprehensive test tak<s
about 16 minutes for cach loop.
Note: Mter a diskette has been put through a destructive test It must
be Initialized before It can be reused. Also. I[ a diagnostic test reports an
error condition. repeat the tesl with aknow:! good diskette 10 verify that
the disk system Is at fault.
When you choose DISK TESTS. the follOWing screen appears
DISK TESTS
1 QUICK TEST
2 COMPREHENSIVE TEST
YOUR a-KlICE? 1
If you choose I. QUICK TEST. the [ollowing screen appears.
QUICK TEST
DESTRUCTIVE TEST (YIN)? N
The prompl DESTRUCTIVE TEST (YIN)? allows you to control whether
or not the data on the disk is destroyed. If you want It destroyed.
answer Y. If you do not want It destroyed. answer N.
25

The prompt. MASTER DISK! 1-3)1 appears. Your response indicates
which disk drive holds the diskette you want to test. When you answer.
the DlSKNAME Is OIled in. and the prompt 40 TRACKS (YIN)? appears
If you selected DESTRUCTIVE TEST. If you answer Y. the diskette ts
,-'I
testeil for 40 tracks_ If you answer N. It Is tested for 35 tracks. Next. the
prompt LOOP (YIN)? appears. It determines whether the test is to be
run once or over and over until you stop it. Answer Y if you want it to
be run repeatedly_ Answer N If you want it to be run just once.
The prompt LOG ERRORS? (YIN)? appears. Your answer determines
whether or !lot any frrors found are to be recorded on another device in
addition to being shown on the screen. If you do not want any other
record. enter N. If you want a record somewhere else. enter Y. If you
enter Y. the prompt DEVICE NAME? appears. You may then enter the
device and flIe name to which you want the log to go. For example. If
you want a record put on the diskette In Drive Two under the Ille name
LOGLIST. enter DSK2.LOGLIST. If you want the logged errors printed
on an attached Solid State Thermal Printer. enter TP as the device
name. Note that you cannot log to the dtsk drive that Is being tested.
When the test Is run. the reC<lrd of any errors looks llke this:
BAD ADDRESS/CODE r.-<l/m
TOTAL ERROR>: m
COMPlETED PASS: m
WDRKNG..... PLEASE WAIT.
PRESS
CLEAR TO ABORT COMMAND
The first number after BAD ADDRESS/CODE Indicates the sector that
was found to be bad. The second number Is the error code for the error
that was found. (See AppendiK B.I An error tone ts generated for each
error found.
26
The number after TOTAL ERRORS: Is the total number of errors that
have been found 90 far In the diskette. The number after COMPLETED
PASS: Is
lbe number of times the test has been run. If you have chosen
not to have the test loop. then only one pass Is made. Otherwise this
test shows how many loops have been run 90 far.
IC you choose to run the comprehensive test. the folloWing screen
appears.
COMPfEHENSIVE TEST
DESTRUCTIVE
MASTER DISK [1-3)7 1
Nole: This test takes about 16 minutes to complete. AU data andlor
programs on the diskette will be lost.
From this point on. the procedure IS the same as for the guick Test.
Just respond to the prompts as they appear 00 the display.
The Comprehensive Test consists of six tests that write to and read
from all of the sectors on the diskette.
SIngle Disk Processing
Option 4on the main selection list of the Disk Manager module Is SET
ALL COMMANDS FOR SINGLE DISK PROCESSING. Choose this option
If you only have one dtsk drive or if you are only going to be using
DSK I. This option speeds up the processes that lhe Command Module
performs. After you choose this opttoo. lhe message SINGLE DISK
PROCESSING
HAS BEEN INITIALIZED appears on the screen. (You
may go back to multiple disk operattons only by leaVing the module
and reentering it.l
Be sure to lnsert a diskette Into the disk drive before selecting any other
commands. The prompts MASTER D1SK(l-3)? and COPY DISK! 1·3)?
wdl automatically be answered each time you choose an optton. and the
disk wtll be accessed Immediately.
27

DISK SYSTEM OPERATION WITH TI BASIC
Your disk memory system can be used conveniently with TI BASIC.
This section discusses saving/loading programs and processing rue data
w~ programs.
The disk system requires some working space In the main memory
(RAM) of the Home Conipuler. The exact amount of space required
depends""n the number of rlles which are allowed to be open at any
given time. In TI BASIC this number is preset to 3. The disk system
then uses 2088 bytes of RAM.
You may use the CALL FILE:S statement to change the number of mes
that may be open. Keep In mind. however. that Increasing the number
of allowable open Illes also Increases the amount of memory used by
the disk system. (See CAU. FILES for more Information.)
Saving and Loading Programs
The disk system stores and retrieves TI BASIC programs qUickly and
eillciently. Approximately 100 flfty-Une programs can be stored on a
single diskette.
The SA VE comma~d Is used to store a program on the diskette. The
format is SAVE
devtce.program-name
The device. is DSK I. DSK2. or DSK3. depending on which disk drive
you want to address. The program·name ts any valid identifying name
you want to give y'lur program. Valid program names can be up to len
characters long and can include any character except the period and
the space characters.
For example. Lo store a program called COLORDEMO on the diskette in
Drive One.
you would enter this command (With the program In
memory):
SAVE DSK1.COLOROEMO
Alternatively. lhe diskette's name can be specified. raLher than the
number of the disk drive. To store a program called COLORDEMO on a
diskette named MYDISK. you enLer
SAVE DSK.MYOISK.COLORDEMD
The computer searches all auached drives until It finds the one thai
contains the diskette named MYDISK.
28
The OLD command ls used to read a program from a diskette. The
fonnat is OLD
device.program·name
When you enter the OLD command. the program you designate by
name is read into the computer's memory. You can then RUN It. LIST
It. or EDIT It - Just as you would use a program entered from the
keyboard.
FIle Naming Conventions
The name of afile can be up to ten characters long. and may use any
characters except the period and the space characters. Valid names for
mes are the same as vaHd names for diskettes.
FIle Processing
There are seven main TI BASIC statements that are used to access files
an diskettes. They are OPE:-I. CLOSE, INPUT. PRINT, EOF, RE:STORE.
and DELETE. In addition, a spectal subprogram named CALL FILES
allows you to
change the number of files allowed to be opened at the
same time. The follOWing dlscusslons of each of these statements relate
to their use with the disk system.
OPEN - The OPEN statemenL prepares a TI BASIC program t~ use dala
files stored on diskettes. It provides a link between afile-number used
in a program and the file on the diskette, and it describes afile's
characteristics so that a program can process or create Lhe file. If the file
already exists, the description that is given in lhe program must match
the actual charactertstles of the file.
29

The OPEN statement has the following general form:
OPEN
"jlle.number:"devlcejlle·name" l,/lle.
orguoizallonll,/lie·typel I.open.modell,record.type)
Tbejile·number and devtcejlle·name must be Included In the OPEN
statemenl. The other Informallon may be In any order. or may be
omitted. If an Item :s omitted. the compuler assumes certain defaults.
which are descrlbed below.
.flle.number - Thejile.number II through 255) Is a9Slgned to a
particular me by the OPEN statemenl. lFlle number 0 Is the keyboard
and screen of the computer. II cannot be used for other flies and Is
always open.) You may a9Slgn file numbers as you wish. with each
me haVing adifferent number.
Thejlle-number ls entered as a number sign (") followed by a
numeric expression that. when rounded 10 the nearest Integer. Is a
number from Ito 255. and Is not the number of afile that Is already
open.
• devicejlle-name - The device. refers to the diskette on which a
particular file Is stored. If afile Is on a diskette In Disk Drlve One. the
device Is DSKI. For Drlve Two. the device Is DSK2. For Drive Three.
the device Is DSK3. Thejile·name may be any valid file name.
Instead of the disk drlve number you may use DSK. followed by the
diskette name. a perlod. and then me jile·name.
OPEflllll :"DSK.DISKmE.ALE1"
The computer wlll search all drives for the diskette with the name
you give.
• flle-organizatlon - Flies can be organized either sequentially or
randomly. Records In a sequential file are read or written one after
the other. Records on random files can be read or written In any
order. They may also be processed sequenllally.
To Indicate which structure the file has. enler either SEQUENTIAL
for
sequential files or RELATIVE for random meso You may
optionally specify the lnllla! number of records on afile by following
the word SEQUE:'oITlAL or RELATiVE with a numenc expression. If
you do not specify thejile-organizallon. the default Is SEQUENTIAL.
For processing files In order. SEQUENTIAL flies are usually
processed more quickly than RELATIVE meso But In some uses.
random flies are more efficient.
30
_jlle.type -Flies can be stored on diskettes either in easlly readable
ASCII characters or In machine' readable binary form. If the
Information Is going to he printed or displayed for people to use.
ASCII format Is usually a better choice. However. binary records take
up less space and are processed more quickly by the computer.
To specify that you wish the file to be In ".SCII formal. enter
DISPLAY. (The length ofa DlSPLAY·type record Is UmlLed to about
150 bytes.) To specify binary formal. enter INTERNAL. If you do not
specify ajiie·type. the default Is DISPLAY.
_open-mode - This entry Instructs the computer lhal lhe file may be
bolh read and ...-rlLten upon (UPDATEI. thai Il may only be read
(INPUT). that It may only be wrllLen to (OUTPUT). or thalli may only
be added to lAI'PEND).
If afile
Is marked as protected. It cannot be wrlllen to and may only
be opened for input. Also. APPEND mode can only be specl!led for
VARIABLE length records. If you do not specify an open.mode. the
computer assumes the default UPDATE.
Note: If an unprotected file already exists on a diskette. specifying an
open-mode of OUTPUT to the same file name writes over tt.e existing
file with lhe new file. You can prevent this by reading all the exlsllng
records so that you move to the end of the file or by using the
RESTORE statement wlUn lhe proper record.
• record.type - Ale records may be all the same length (FIXEDI or
may vary In lenglh IV ARIABLE). If they are all the same length. any
thai arc shorter are padded 10 make up lhe difference. Any lhat arc
longer may be truncated to the proper length. Flies that have FIXED·
length records are processed faster than files wllh VARIABLE·length
records.
If you like. you may specify ama><lmum length of a record 'oy
follOWing VARIABLE or FIXED with a numeric expression. The'
maximum lengUn for a VARlABLE file Is 254 bytes. and the
maximum for aFIXED file Is 255 bytes. If you do not specify a record
length. the default Is 80.
RELATIVE flies must have FIXED lenglh records. If you do not
specify arecord· type for aRELATIVE file. lhe default Is FIXED.
SEQUENTIAL rues
may be either FIXED or VARIABLE. If you do not
specify arecord· type for aSEQUENTIAL file. lhe default Is
VARlABLE. A AXED·length file may be reopened for either
SEQUENTiAL or RELATIVE access Independent of prevlou.jile-
organtzallon assignments.
31

OPEN '243: A$,INTERNAL
The following are examples of OPEN .tatements.
OPEN'1: "OSK1.MYFILE" Creates or reopens afile on the
diskette In Drive One with a name
of MYFILE. The file is
SEQUENTIAL. kept in DISPLAY
format.
in UPDATE mode with
V!\RIABLE length records with a
maximum length of 80 bytes.
(These are the default attributes
assigned by the computer.)
OPEN '23: "DSK.MYDISK.X".RB.ATIVE Creates or reopens afile named X
1lXJ,INTERNJll,DUTPUT.RXEO 80 on the diskette named MYDISK in
whichever drive it is locaied. The
file is REL!\TlVE. kept in
INTERNAL format, in OUTPUT
mode with FIXED length records
with a maximum length of 80
b!les. Initially. 100 records are
made available for the file.
If AS
equals DSK2.ABCD, creates or
reopens a file on the diskette in
D:ive Two with a name of ABeD.
The file is SEQUENTIAL. kept in
INTERNAL format, in UPDATE
mode with VARIA8LE length
records wllh a maximum length of
80 bytes.
CLOSE - The CLOSE stalement discontinues the assoctation between
afile and a program, After the CLOSE statement is performed, the file
Is not
available unless it is opened again with an OPEN statement. Files
may optionally be deleted by adding :DELETE to lhe end of the CLOSE
statement.
The CLOSE stalemenl has the follOWing general form:
CLOSE It]lle-number I:DELETE}
The]lle-number is lhe number which you used in the OPEN statement
to open the file.
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If you do nal close afile. data on it may be lost. If a program ends due
to aBREAK stalement. due to pressing SHIFT C(CLEAR), or because of
an error, files may not be closed even if you have aCLOSE statement in
the program. However. you can close the files Droperly by entering
NEW. or BYE if you wish 10 leave BASIC. Editing the program also
aulomatically closes any open files.
Note: If you leave TI BASIC by pressing SHIFT Q(QUIT), data may be
lost. Leave TI BASIC only by entering BYE when you are processing
files.
INPUT -
The INPUT statement. used with diskettes. allows you to read
data from files. It can only be used with files opened in INPUT cc
UPDATE mode.
The INPUT stalement has the follOWing general form:
INPUT
Itjlle-number I.REC record-numberl :variable-ltst
Thejlle-number and a variable-Itst must be included In the INFUT
statement. The record-number may optionally be included when
reading random-access files.
.)lle-number - The ]lIe-number is the number assigned to a
particular file by lhe OPEN statement. The ./lIe-number is entered as
a number sign (It) followed by a numeric expression that. when
rounded to the nearest integer, is a number from 1to 255 and is the
number of afile thai is open.
• record-number -A record-number refers to the record on the file
which you want to read. The record-number can only be specified for
RELATIVE files. (SEQUENTIAL files
are read In sequential order.)
• varlable-Itst - The variable-list Is the list of variables inlo which you
want the data from the file to be read. It consists of string or numeric
variables separated by commas.
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INPUT 113:A,B,C,
INPUT 1123:X,A,Llili
INPUT 1111, REC 44:TAX
.}lle-number - The }lIe-number Is the number assigned to a
particular me by the OPEN statement: The _nre-number Is emered as
a number sign ("I followed by a numeric expression that. when
rounded to the nearest Inleger, is a number from Ito 255 and Is the
number of ame that Is open.
•
record-number - A record-number refers to the record on tt.e Ille
which you want to write. The record-number can only be specified
for random mes IRELATIVEI.
•
print-list - The prtnt-ttst Is the list of values that you want t,) put on
the file. Jt consists of string or numeric variables or constants
separated by commas. colons. and semlcolcns.
The following are examples of PRINT state men Is.
PRNT 111 :XiIi PUIS the value of XS into tt.e next
position of the me that was opened
as "1.
Puts the value of X, A, and "TIMES
4" into the next record tn the file
that was opened as "23.
Puts the siring eonstant "TAX"
Into record number 44 of the file
that was opened as "11.
Puts the values of A, B. anc CInto
the next three positions In the file
that was opened as "3. The comma
after C creates a pending print
condition. When the next PRINT
statement Is performed. one of the
following actions occurs:
If the next PRINT statemenl has no
REC clause. the computer places
the data Immediately following the
previous cata.
If the next PRINT statement has a
REC
clause. the computer writes
the pending print record onto the
file at the position indicated by the
Internal counter and performs the
new PRINT-REC statement as
usual.
PRNT 1111 ,REC 44:"T AX"
PANT 113:A.B:C,
PANT 1123:X A:"TIMES 4"
The following are examples of INPUT statements.
INPUT 111 :XiIi Puts into XS the next value
available tn the me that was opened
as "I.
Puts Into X. A, and LLS the next
three values from the me lhal was
opened as "23.
PUIS Inlo TAX the first value of
record number 44 of the file that
was opened as #11.
Puts Into A, B, and C the next three
values from the file that was
opened as "3. The comma after
C creates a pending input
mnditlon. When the next INPUT
statement using this file Is
performed. one of lhe following
actions occurs:
If the nexllNPUT statement has no
J;,EC clause, the computer uses the
data beginning where the previous
INPUT statement stopped.
If the next INPUT statement
includes aREC clause, the
cDmputer terminates Ihe pendtng
Input condition and reads the
specjfled record.
PRINT - The PRINT statement allows you to wrlle dal. onto files on
diskettes. It can only be used wIth flies opened In OUTPUT. UPDATE,
or APPEND mode.
The PRfNT statement has the follOWing general form:
PRINT
"}lIe-number I.REC record-numberll:prlnt-tlstl
The}lle-nwnber must be Included In the PRINT statement. The record-
number may optionally be Included when writing Lo random-access
lRELAT1VEll1les. The print-Itst Is also opttonal.
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