Radio Shack PC-2 TRS-80 User manual

TERMS AND CONDITIONS OF SALE AND LICENSE OF RADIO SHACK COMPUTER EQUIPMENT AND SOFTWARE
PURCHASED FROM A RADIO SHACK COMPANY-OWNED COMPUTER CENTER. RETAIL STORE DR FROM A
RADIO SHACK FRANCHISEE DR DEALER AT ITS AUTHORIZED LOCATION
LIMITED WARRANTY
CUSTOMER OBLIGATIONS
A CUSTOMER assumes full responsibility fhat this RadiO Shack computer hardware purchased (the ·lqulpmenn. and any COpieS of RadiO
Shack software Included with the Equipment or licensed separately (the "Software') meets the specifications. capacity. capabilities.
versatility, and other requllements of CUSTOMER
CUSTOMER assumes tull responsibility for the conditIOn and eftectlveness of fhe operating environment in which the Equipment and Software
are to function. and for ifs installaflon
II. RADIO SHACK L1MITEO WARRANTIES ANO CONOITIONS OF SALE
A For a period of nmety (90) calendar days from fhe date of the RadiO Shack sales document rec8lved upon purchase of the Equipment. RADIO
SHACK warrants to the original CUSTOMER that the Equipment and the medium upon which the Software is stored IS free from manufactUring
detects. THIS WARRANTY IS ONLY APPLICABLE TO PURCHASES OF RADIO SHACK EQUIPMENT BY THE ORIGINAL CUSTOMER FROM
RADIO SHACK COMPANY-OWNED COMPUTER CENTERS. RETAIL STORES AND FROM RADIO SHACK FRANCHISEES AND DEALERS AT ITS
AUTHORIZED LOCATION. The warranty IS vOid If the Equipment's case or cabinet has been opened. or it the Equipment or Software has been
subjected to improper or abnormal use. If a manufactUring defect IS discovered during the stated warranty period. the defective Equipment
must be returned to a RadiO Shack Computer Center, a Radio Shack retail store. participating Radio Shack franchisee or Radio Shack dealer
for repall. along With a copy of the sales document or lease agreement. The original CUSTOMER'S sole and exclUSive remedy In fhe event of
a defect IS limited to the correction of the defect by repall. replacement, or refund of the purchase price, at RADIO SHACK'S electIOn and sale
expense RADIO SHACK has no obligation to replace or repall expendable Ifems
B. RADIO SHACK makes no warranty 3S to the deSign, capability, capacity. or SUitability for use of the Software, except as prOVided in this
paragraph. Software IS licensed on an "AS IS" baSIS, Without warranty The original CUSTOMER'S exclUSive remedy, in the event of a
SoHware manufactUring defect. IS ItS repall or replacement Within thirty (30) calendar days of the date of the RadiO Shack sales document
received upon license of the Software. The defectIVe Software shall be returned to a RadiO Shack Computer Center. a Radio Shack retail store,
partiCipating Radio Shack franchisee or RadiO Shack dealer along With the sales document
Except as provided herein no employee, agent, franchisee. dealer or other person is authorized to give any warranties of any nature on behalf
of RADIO SHACK
Except as prOVided herein, RADIO SHACK MAKES NO WARRANTIES, INCLUOING WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE.
Some states do not allow limitations on how long an implied warranty lasts. so the above Ilmltatlon(s) may not apply to CUSTOMER
III. LIMITATION OF LIABILITY
A. EXCEPT AS PROVIDED HEREIN. RADIO SHACK SHALL HAVE NO LIABILITY DR RESPONSIBILITY TO CUSTOMER DR ANY OTHER PERSON
DR ENTITY WITH RESPECT TO ANY LIABILITY, LOSS DR DAMAGE CAUSED DR ALLEGED TO BE CAUSED DIRECTLY DR INDIRECTLY BY
"EQUIPMENT' DR "SOFTWARE" SOLD, LEASED, LICENSED DR FURNISHED BY RADIO SHACK, INCLUDING, BUT NOT LIMITED TO, ANY
INTERRUPTION OF SERVICE, LOSS OF BUSINESS DR ANTICIPATORY PROFITS DR CONSEQUENTIAL DAMAGES RESULTING FROM THE
USE DR OPERATION OF THE "EQUIPMENT' DR "SOFTWARE" IN NO EVENT SHALL RADIO SHACK BE LIABLE FOR LOSS OF PROFITS. OR
ANY INDIRECT, SPECIAL, DR CONSEQUENTIAL DAMAGES ARISING OUT OF ANY BREACH OF THIS WARRANTY DR IN ANY MANNER
ARISING OUT OF DR CONNECTED WITH THE SALE, LEASE, LICENSE, USE OR ANTICIPATED USE OF THE "EQUIPMENT' DR "SOFTWARE"
NOTWITHSTANDING THE ABOVE LIMITATIONS AND WARRANTIES, RADIO SHACK'S LIABILITY HEREUNOER FOR DAMAGES INCURRED BY
CUSTOMER DR OTHERS SHALL NOT EXCEED THE AMOUNT PAID BY CUSTOMER FOR THE PARTICULAR 'EQUIPMENT" DR "SOFTWARE"
INVOLVED

RADIO SHACK shall not be liable for any damages caused by delay in delivering or furnishing Equipment and/or Software
No acflon arising out of any claimed breach of this Warranty or transactions under this Warranty may be brought more than two (2) years
after the cause of action has accrued or more than four (4) years after the date of the Radio Shack sales document for the Equipment or
Software, whichever first occurs
Some states do not allow the limitation or exclusion of incidental or consequential damages, so the above limitatlon!s) or excluslon(s) may
not apply to CUSTOMER
IV. RADIO SHACK SOFTWARE LICENSE
RADIO SHACK grants to CUSTOMER a non-exclusive, paid-up license to use the RADIO SHACK Software on one computer, sublect to the follOWing
proVIsions:
A Except as otherwise provided in this Software License, applicable copYright laws shall apply to the Software.
B. Title to the medium on which the Software IS recorded (cassefte and/or diskette) or stored (ROM) is transferred to CUSTOMER. but not title to
the Software.
C. CUSTOMER may use Software on one host computer and access that Software thrOugh one or more terminals if the Software permits thiS
function
CUSTOMER shall not use, make, manufacture, or reproduce copies of Software except tor use on one computer and as is speCifically
prOVided in this Software License Customer is expressly prohibited 'from disassembling the Software
CUSTOMER IS permitted to make additional copies of the Software only for backup or archival purposes or if additional copies are required in
the operation of one computer with the Software, but only to the extent the Software allows a backup copy to be made. However, for
TRSOOS Software, CUSTOMER is permitted to make a limited number of additional copies for CUSTOMER'S own use.
CUSTOMER may resell or distribute unmodified copies of the Software provided CUSTOMER has purchased one copy of the Software for each
one sold or distributed. The provisions of thiS Software License shall also be applicable to thrrd parties receiving copies of the Software from
CUSTOMER
G All copYright notices shall be retained on all copies of the Software
V. APPLICABILITY OF WARRANTY
A. The terms and conditions of this Warranty are applicable as between RADIO SHACK and CUSTOMER to either a sale of the Equipment and/or
Software License to CUSTOMER or to a transaction whereby RADIO SHACK sells or conveys such Equipment to a thrrd party for lease to
CUSTOMER
The limitations of liability and Warranty provisions herein shall Inure to the benefit of RADIO SHACK, the author, owner and/or licensor of the
Software and any manufacturer of the Equipment sold by RADIO SHACK.
VI. STATE LAW RIGHTS
The warranties granted herein give the original CUSTOMER speCifiC legal rights, and the original CUSTOMER may have other rights which vary
fro 10 state to state

ASpecial Note to Our Customers ...
To make the TRS-80 PC-2 available to you as quickly as possible, we're providing this Owner's Manual which will
explain how to use the PC-2.
Throughout this manual, we've made reference to the book "TRS-80 PC-2 Programming Guide" (optional/extra).
This manual, which should
be available in the Summer of 1982, will be acomprehensive PC-2 BASIC Programming
Manual.
In the meantime, many
of your programming questions can be answered by referring to another Radio Shack book
called "Problem Solving on the TRS-80 Pocket Computer" (Catalog number 62-2312).
Thank
you,
Radio Shack

To Our Customers ...
Besides being one of the smallest computers that Radio Shack provides, the TRS-80 PC-2 IS one of the most
powerful and versatile computers of its size available anywhere.
Its
powerful capabilities, as well as its "expandability", make it the ideal personal computer for business, scientific,
engineering,
or personal use.
In spite of its size and power, however, the Pocket Computer can be quite simple to use. In fact, you can
determine just how technical amachine you want it to be.
At its simplest level of operation, you can use Radio Shack cassette programs, RAM Modules, or ROM Modules.
All you will need to know is how to load and run acassette program or insert aprogram cartridge into the
Computer.
At a slightly more involved level of operation, you may want to write your own programs. If you are abeginner,
read this operation manual, then read a
PC-2 programming guide.
If, however, you are already an experienced programmer and are familiar with BASIC, read this operation manual.
For
your convenience, we ve included aLanguage Reference Summary in the appendix which lists PC-2 commands,
their syntax, and examples of use.

About This Manual
This manual contains operating instructions for the PC-2. The Language Reference Summary includes only those
commands which can be used by the Computer when it is not connected to an optional device (such as Printer/
Cassette Interface).
For adescription of the commands which can be used with an optional device, see that peripheral's operation
manual.
For instructions on programming the Computer, see a PC-2 programming manual.
2

Contents
Customer Information. .................................................................... .. 3
Welcome
to the World of Pocket Computing! 4
1IDescription
of the Pocket Computer 5
Keyboard Display Rear
Panel
2/Setting Up the Pocket Computer 13
Starting-Up Battery Installation External Power Supply
3/Using the Pocket
Computer 19
Using the Keyboard The PC-2 As ACalculator PC-2 BASIC
4/Care and Maintenance 87
5/Specifications 89
Appendix A/Language Reference Summary 91
Appendix B/Error Codes 103
Customer Information
3

Welcome to the World of Pocket Computing!
The TRS-80 PC-2 system consists of:
• A 66-Key keyboard for inputting programs and data into the Computer.
• A 26-character Display to exhibit data results and other information. The Display can also be used to exhibit
graphics (7 X156 dot pattern).
• An expanded BASIC Language that includes graphic commands.
• A CMOS microprocessor with more power than the mammoth computers of a few years ago.
•Read Only Memory (ROM) which contains the BASIC language.
•Random Access Memory (RAM) for storage of programs and data even when the Computer is turned off
(amount is expandable up to 24K, optional/extra).
•Expansion area for plug-in of optional RAM, ROM, or combination RAM/ROM Modules.
• A Cassette/Printer Interface for long-term storage and hard-copy output of programs and data (optional/extra).
Requires aseparate cassette recorder (optional/extra) for cassette storage.
• Battery powered for portable operation or DC power adaptor (optional/extra).
4

.----, ,-.....~-_.....---,,--.~---------.--.-.---,,-
1/Description of the Pocket Computer
Before using the PC-2, it's important that you become familiar with it. Carefully read the following section.
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Figure 1. PC-2 (Front View)
5

When you're ready to turn the Computer OFF, press this key.
Turns the PC-2 ON. If pressed while you are running aprogram, execution will "break" (inter-
rupt).
Allows you to execute programs at line numbers which have had certain keys assigned to them as
the first character of the line. Other keys permanently act as command keys after .@f) is pressed.
For instance, if (DEF) CQJ is pressed, the command INPUT will be displayed.
8) CIT) ~ @) Function Keys. These keys are reserved for your use. You can assign to them any values,
commands,
or statements you desire. When (SHIFT) is pressed before any of the Function
Keys, the character above the key will be used.
In Lowercase
Option Mode (SMALL), any alpha-key pressed after this key will be uppercase. In
Normal (uppercase) Mode, any alpha-key pressed after this key will be lowercase. Press this key
before pressing key which has acharacter above it and the character above it will be displayed.
®
(j)
®
C£J ~ IT) Alphabet keys.
C:J (ill ~ W Number keys.
?
CD Division Key. Allows you to divide numeric values.
will display a question mark (n.
Pressing (SHIFT) before pressing this key
Multiplication Key. Allows you to multiply numeric values. Pressing (SHIFT) before pressing
this key will produce acolon ( :).
6

,
@G
,
@CB
CA
@ (Cl)
Subtraction Key. Allows you to subtract numeric values. Pressing (SHIFT) before pressing this
key will produce acomma (,).
Addition Key. Allows you to add numeric values. Pressing (SHIFT) before pressing this key produce
asemicolon (;).
Clear Key. Pressing this
key will clear the Display and "release" errors. Pressing (SHIFT) before
pressing
(Cl) will activate the CA (reset) function. This will clear the display and reset the Com-
puter.
Pressing this key will specify either the RUN or PROgram Operation Mode. Pressing (SHIFT) (MODE)
will specify RESERVE operation mode.
< >
@ TCD Parentheses Keys. Pressing (SHIFT) before pressing these keys will produce the Greater Than/Less
Than
symbols .
@
..
CD
@
7l:
CD
@ (SMl)
@GJ
Display previous program line. Pressing (SHIFT) before pressing this key will produce asquare
root (v) sign and allow you to compute the square root of a numeric value.
Display
next program line. Pressing (SHIFT) before pressing this key will produce a PI ( 11" )sign
and
allow you to use astored value of PI in your computations.
Lowercase Option Key. Press once and lowercase (small) letters will be used. Press again and
normal (uppercase alpha-) character display will be used.
Reserve Mode Change. Since each
of the six Function Keys can be assigned values in each of
three modes -1/II/III -pressing this key will move the Computer to the next Reserve Mode.
7

DEL
@G]
Recall Key. Pressing this key one will display the function key menu for the current reserve mode
(l/II/III). Pressing this key again will recall the contents of the original display.
Spacerbar Key. Pressing this key will advance the Cursor, leaving a blank space. Press (SHIFT)
before pressing this key and the Exponential symbol will be produced and allow you to raise a
numeric expression to a power.
When you press this key, whatever you previously typed will "enter" the Computer's memory.
This key is similar to the Carriage Return key on a typewriter. You must press (ENTER) before the
PC-2 will accept alphanumeric input from the keyboard.
Backspace Key. This key allows you to move the Cursor to the left without erasing previously
typed characters. Pressing (SHIFT) before pressing this key will DELete whatever character the
Cursor is "on top of."
INS
@CB
Forward Key. Pressing this key allows you to move the Cursor to the right without erasing pre-
viously
typed characters. Pressing (SHIFT) before pressing this key will allow I NSertion of characters
directly before the character the Cursor is "on top of."
@ Printer/Cassette Interface Connector Cover. Remove the Cover to attach the PC-2 to the Printer/Cassette
Interface. See Printer/Cassette Interface owner's manual for details. (And attach the Cover to the
bottom of the I nterface so you won't lose it!)
8

CD
0
(2)
8) ®®(j) ®
{-
{- {- {- {- {- {-
{-
BUSY SHIFT SMALL DEG
RUN
DEF
•]
Figure 2.
Sample PC-2 Display
CD BUSY Program Execution Indicator. This Indicator is on during program execution. When program
execution is complete, the Indicator goes off. The PC-2 will not turn off (manually by pressing
@ or automatically after seven minutes) when the BUSY Indicator is on.
o SH 1FT Sh ift Key Indicator. This I ndicator is on whenever (SHIFT) has been pressed. Press any key (except
(SML) or CQID )and the Indicator wi II go off.
G) SMALL Lowercase Option Indicator. This Indicator is on whenever the Computer is in Lowercase Option
Mode (the Computer can display either upper- or lowercase letters). Press (SML) to turn the Indi-
cator on; press again to turn off.
Angular Measurement Indicator. This Indicator will display the current unit of angle for the input of trigono-
metric functions: DEG for "degrees." (To compute in degrees, type DEGREE (ENTER) ); RAD for
"radians." (To compute in radians, type RADIAN (ENTER) ); GRAD for "gradients." (To compute
in gradients, type GRAD (ENTER) ). The Computer will use ameasurement mode until you tell it
to do otherwise.
a

®Operation Mode Indicator. This Indicator will display RUN when you are in the RUN Mode. You must be
in RUN Mode to execute ("run") programs or perform manual calculations (use the Computer like
acalculator), This
Indicator will display PRO when you are in PROgram Mode. You must be in
PRO Mode
to enter programs into the Computer's memory. Press (MODE) to go from one mode to the
other.
Press (SHIFT) (MODE) and the Indicator will display RESERVE. In this mode, you may assign
values, commands, or statements to the Function Keys as well as set up Function Key menus.
®DEF Definable Mode Indicator. This Indicator lights up when you press @ill .When the PC-2 is in the
RUN mode, pressing
@IT) followed by aprogram label key (see Table 2) will allow you to run a
labeled program. In any mode, pressing
(ill) followed by acommand instruction key (see Table 1)
allows easy use of keywords.
(jJ l/1I/1II Reserve Mode Indicator. This Indicator tells you which Reserve Mode the PC-2 is in. To change
modes,
press W . All six Function Keys ( em ~ CE§) ) can be defined in each of the three
modes
O/II/IIO for a total of 18 different val ues.
® • Battery Indicator. As long as this Indicator is ON, the Computer has sufficient power to operate.
When this
Indicator is OF F, the Computer's batteries are too "low" to insure correct operation.
Replace
them or connect the Computer to an external power supply.
10

®
/000
1(\
t=:::t=J
..---
IV
~
(-
[
~o
(-
~o
'--
I--
00
CD
Figure 3. PC-2 (Rear Panel)
CD RAM/ROM Module Slot. Insert RAM or ROM Modules into this slot. See your RAM/ROM Module user's
guide
for specific details.
o ALL RESET Button. If the PC-2 ever "hangs up, , use a ball-point pen to press this button while pressing
(ON) . Hold the button and key down for about 15 seconds. Be aware, however, that memory will be erased
(I. E. you'll lose any programs in memory).

® Identification Tag. Place the permanently adhesive Identification Tag here.
o Battery Cover. Remove this Cover to gain access to the batteries which supply power to the PC-2. Be careful
not to lose the screw which secures the Cover; it is not attached to the Cover when removed.
® External Power Supply Jack. If you have an external power supply adaptor (optional/extra), plug it in here.
12

2/Setti ng Up the Pocket Co mputer
Start-Up
To turn the PC-2 on, simply press the (ON) key.
The Computer should respond with the Ready prompt (> ) and indicators that tell you:
• If the Computer was last used to compute degrees, radians, or gradients.
•Which Operation Mode the Computer is in (PROgram, RUN, or RESERVE Mode).
•Which of the three Reserve Modes 0, II, or III) has been selected.
• Whether or not there's enough battery power to use the Computer.
On start-up, the PC-2 uses all mode settings that were being used when the Computer was turned off.
For instance:
....
SHIFT SMALL DEG RUN
Figure 4. Sample Display On Start-Up

When the Computer is turned on, there are four different power-up messages which can be displayed:
DEG
:: i ... : i··· Ii:::;:::: i<:
PRO
This message can appear on power-up after:
• Turning the Computer on for the first time.
• Battery replacement.
•Pressing ALL RESET.
To clear the Display and begin computing:
1. Press @ .
2. Be sure you are in PROgram Mode. If not, press ~ until PRO is displayed.
3. Type: NEW0 (ENTER) .
4. Press (SHIFT) (M~) , The PC-2 will then be in RESERVE Mode.
5. Type: NEW (ENTER) .
This procedure will clear the PC-2's Main and Auxiliary memory areas.
CHl-CK t;
OEG
14
PRO
DEF

If this message appears, it means that one of the peripheral devices (such as aPrinter/Cassette Interface) is not
operating properly. Press @) to clear the display and continue computing.
".
",
DEG RUN
II .]
The Display will look like this on normal power-on and when optional devices or memory modules are connected.
DEG
PRO m.]
This is asample display. Whenever the PC-2 turns itself off automatically (when the PC-2 has not been busy and
a
key has not been pressed for seven minutes), press (QR) to turn the Computer back on. When you do so, the
previous display will appear.
Note: If the ARUN statement is used as the first command in aprogram, the PC-2 can start up with the BUSY
I ndicator ON.
If you press (ON) while aprogram is running, it serves as a BREAK key. The program will stop execution and
display
the line number at which the "break" took place.
Press CTI and the portion of the program line that had just executed will re-appear. Press CIJ again, and the
next program step will execute. Type CaNT (ENTER) to continue program execution after abreak.
15

Turning the Computer OFF
When you're ready to turn the PC-2 OFF, press the (Qffi key. The Display will then clear (be erased).
If the BUSY indicator is on, press BREAK before pressing (Qff) .
When it is turned off, the PC-2 remembers programs, mode settings, Definable Keys, etc. that were being used
when the Computer was turned on. When you turn the Computer back ON, those settings will be displayed and
the program will be in memory.
(The PC-2 forgets only when you remove the batteries without first connecting an external power supply or when
you clear memory!).
Note: You cannot turn the Computer off when the BUSY light is on.
Battery Installation
We suggest you use Radio Shack Type AA Alkaline batteries (Radio Shack Catalog Number 23-552).
To install the batteries:
1. If you wish to preserve the contents of memory, connect the PC-2 to an optional external power supply.
2. Place the PC-2 upside down on a soft, non-abrasive surface (such as a foam rubber pad).
16