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NOTE
Aitair ,s a t r a d e m a r k of
Miis.
inc.
ALTA!R T!MESHAR!NG BASHC
CHALLENGES LARGE COMPUTER SVSTEMS
By Susan 8. Dixon
Aitair
Timesharing
microcomputers
dynamic
package
capabilities
dominated
that
BASiC for
is a
unique and
with
powerful
chahenge
by l a r g e r ,
a fietd
more
costiy
computers.
Aitair
Timesharing
Aitair Timesharing
BASIC and
Disk
BASiC are
magnified versions of the powerful and
efficient Aitair Extended BASiC. Each
version includes increased capabilities to
accommodate as many as eight different
programs running simuttaneously and
independentiy within the system.
Typical Aitair T i m e s h a r i n g B A S I C s y s t e m . inclu<
Floppy D i s k s a n d Aitair 8 8 0 0 b Turnkey mode],
s u p p o r t s u p t o eight u s e r s
instantaneous Keyboard Response
Input and output are interrupt driven
] Aitair B-100 C R T s . Aitair
air T i m e s h a r i n g B A S I C
—Extensive diagnostics for program
!/0 Device Support
debugging.
and fulty buffered to provide virtually
A variety of input devices can be
instantaneous keyboard response even
linked to Aitair Timesharing BASiC and
—Automatic line numbering.
when the system supports the m a x i m u m
Aitair Timesharing
— Both
number of users. The output
flexibility permits the use of CRT's for
Sharing
high-speed
oriented text editor with tine and
buffers
empty more quickly than they are fitted,
data
Disk BASIC. This
manipulations and
so it will appear the CPU is dedicated to
T e i e t y p e s ^ and hard
each individual termina!.
when hardcopy output is required.
High Speed Systematic J o b Rotation
Aitair
copy
Timesharing
Disk
BASIC
facilitates the listing of programs on a
round-robin system, the CPU suspends
line printer. Programs await listing in a
operation
queue to prevent mixing different jobs.
of a job c u r r e n t l y
being
executed, stores the address of the next
Users receive a message
instruction and moves to the next job.
printer is unavailable.
Each
job is served a hundred
milii-
second stice of its program.
as a Fixed
Aitair
Partition
provides
Time
line-
manipulation
capabilities.
Educationa) Appiications
A single Aitair 8800b loaded with
either version of Timesharing BASIC can
be
utilized
by s e v e r a !
students
performing independent operations. One
Storage and
another
makes
use of
Timesharing
BASiC's extensive diagnostics to debug a
Timesharing
rapid
furnish
student practices program development,
Program
Loading Capabiiities
Partitioned Memory Locations
Established
Versatite
if the line
BASiC
character
terminals
Operating within a highty efficient
versions of A i t a i r
loading
Disk
BASiC
and program
program white several other students
calculate complicated
equations. AH
System, each job is confined to a unique
retrieval since all programs reside on a
program activity occurs simultaneously
area of memory. Users may then access
floppy disk. Read and modify passwords
with no discernable response delay.
only their individual jobs, not the system
may be specified for program fixes to
or other jobs. This protects jobs from
limit access by other users.
alteration or destruction. The size of the
Aitair Timesharing
BASIC can be
memory area must be established with a
loaded
minimum
cassette. Programs m a y be stored for
o^ 1024 b y t e s
during
from
paper
tape
initialization. Memory areas m a y be of
later use on paper tape.
different sizes, depending on need. Each
Other Features
program area contains:
—BASiC program text
—Variabte and string space
—Work space
—Approximately
300 bytes of the
timesharing system
C/N June. 1 9 7 7
or a u d i o
—Control of a specific job m a y be
Computer-oriented
education
need
not be limited to programming classes.
An Aitair
Timesharing
System
is a
valuabie visual tool in science, math and
engineering
classes
and as an
introduction to the various aspects of
computer technology to solve real world
problems.
transferred from one terminal to
another with a single command.
An
—Various control characters allow
stimulates
suspension and resumption of each
job without ioss of data.
Aitair
Timesharing
interest
System
a n d provides a
vehicle for discussion for the younger
CONTINUED
ONE
N
e
w
^
F e a t M ^ a S
a ^ s a o n
A
U
T
Those of you who have been asking
for a Turnkey version of the Aitair 3800b
O
-
S
T
A
R
T
By Dar Scott
machine tooi or some other dedicated
again. The indicators show that an t/O
application.
operation is in progress, a HALT state
computer m a y now stand up and cheer,
The seriai input/output channel is
has been entered, interrupts are enabied
because the Turnkey version of " t h e
essentially half of a 2StO board. With the
or an interrupt is in progress. The tights
mainframe of the 70's" is now available.
The Turnkey version incorporates alt
addition
channel
of a
jumper
interface
selection,
is compatible
and
the
with
switches
the good quality construction and good
TTY, RS-232 or TTL signals. This means
operation.
looks of the Aitair 8800b computer. But
that the Turnkey version can operate
CPU Board
just because the Turnkey doesn't have a
with
front panel or a front panei interface
arrangement
board
equipment
doesn't
mean
it's
merely
a
almost
any
terminai
with
no
or
i/O
interface
necessary. The i / O
provide the
ports
The CPU board is the standard Aitair
8800b CPU
board.
It consists of five
major functional blocks:
stripped-down version of the Aitair 8800b
associated with the seria) input/output
computer, it has some unique features,
channel can be assigned to any 128 i / O
"
inciuding
port pairs by switch selection.
— 8212 Status Latch
the new T u r n k e y
Moduie
minimum
facilities to monitor and control system
— 8080A CPU Chip
8224 Ciock Generator Chip
board. With this board at) the functiona)
The I K R A M and the IK P R O M can
units of the computer — the CPU, R A M
each be assigned to any IK block within
and P R O M memory sense switches and
the ful) Aitair 8800b address space by
The CPU
board is, in most respects,
serial i / O — can be contained on just two
switch selection. The P R O M used Is the
identical
to t h e 8800b C P U
1702A-a256-byte by 8-bit PROM.* A disk
described in a previous Computer Note*
bootstrap
articie (see p. 1, 4-5 in J u i y
circuit boards, which are supplied in the
standard Turnkey version package.
But the most important advantage of
loader
PROM,
a
general
— Drivers and Receivers
"
Power-On-Ctear Circuit
board
C/N).
purpose mutti-bootloader P R O M and a
However, the Power-On-Ciear Circuit is
the Turnkey Moduie is that it contains
small monitor P R O M are aiso available
especiaHy i m p o r t a n t in the Turnkey
AUTO-START,
from MiTS for use with the Turnkey
version because it generates a puise to
version.
reset the system. The circuit is designed
which
ailows
the
computer to begin executing a program
in P R O M as soon as the power is turned
on or the START is actuated.
The switches on the Turnkey version
front pane) are the P O W E R
The Turnkey Module includes the
switch,
so t h a t
even
generate
a
short
retiable
power
outages
Power-On-Ciear
which has a key lock for system security;
puise. The Turnkey Moduie uses this
START, which Initializes the CPU and
puise to reset the C P U
— AUTO-START
initiates
P R E S E T low. The CPU board extends
— IK bytes each of R A M and P R O M
and RUN/STOP, which allows execution
this
of a program to be stopped and started
starting before the Power-On-f*tear puise
following functional parts:
memory
the AUTO-START
sequence;
by
putting
putse to prevent the CPU
from
" " Serial t/O Channel
— Control for the front panel
Required Hardware
A L F A M
— Miscellaneous control and
T i M E S H A F M N G
housekeeping logic
The AUTO-START feature is the key
START switch is actuated, the computer
is
forced
instruction
to
begin
at
the
executing
memory
the
iocation
specified by switches on the Turnkey
Module. This means that when the power
goes on, the computer can be m a d e to
start a loader program or a
automatically
without
monitor
keying
in
a
bootstrap loader from the front panel.
Alternately, the computer can be m a d e
to start a custom applications program
at start-up. This should appeal to users
who want to build the computing power
of an Aitair 8800b into a lab instrument,
CONTINUED
student.
Chiidren
versions
of
Aitair
find
it
—Aitair 8800 series m a i n f r a m e and
particutarly
CPU
fascinating to use a computer to soive
—A m i n i m u m of 32K R A M
arithemetic problems.
—Vector )nterrupt/Rea) Time Ctock
Scientific and Engineering Uses
board
Engineering firms and scientific labs
currently
using
—Up to 4 2SI0 boards to interface
programmable
terminals (no other types of t/0
calcuiators will benefit from the muiti-
boards can be supported).
purpose capabilities of a microcomputer
—Line printer (optionat for Attair
for complex math routines and statisticai
Timesharing Disk BAStC).
manipulation. An Aitair 8800B operating
with Timesharing
BAStC provides a
The following products are optionat
for Attair Timesharing BASIC toading
number of individuals with access to
and
graphic or tabular output in addition to
Disk BASiC.
the following mathematics)
functions:
SIN, COS, TAN, LOG, SQR, SGN, ABS,
INT and R N D .
FOURTEEN
both
Timesharing BASiC.
to the Turnkey version's ease of use.
When the power is turned on or when the
The foilowing hardware is needed to
support
B A S ! C
required
for Aitair
Timesharing
—An A)tair ftoppy disk drive and
controiler.
—88-PROM board.
C/N June. 1 9 7 7
NEW ALTAtR M!N!D!SK
STORES OVER 71K
By Thomas Durston
is completely removed from all i / O and
memory boards.
The mother board for the Turnkey
version of the Aitair 8800b computer has
18 usable slots.
Power Suppty
The power supply for the Turnkey
version is the s a m e as that for the
standard
power
Aitair 8800b computer. This
supply furnishes
voltages
the following
at the indicated
currents:
8 volts at 18 amps
+ 18 volts at 2 amps
-18 volts at 2 amps
full
load
The miniaturization of mass storage
is just one of the exciting features of the
Drive through two Minidisk
Controller Cards that plug into the Aitair
new Aitair Minidisk System. Designed to
Bus. All control, status and data 1/0
work with the Aitair 8800b, the Minidisk
signals are handled through three 1/0
has a storage capacity of over 71K bytes
ports
per diskette with an access time of iess
Controller. To insure m a x i m u m life of
dedicated
to t h e
Minidisk
the drive motor, a timer in the Controller
than three seconds.
Aitair Minidisk BASiC, resides in the
lower 20K of memory and provides the
turns the system off if the Minidisk is not
accessed for five seconds.
disk utilization routines. Aitair Minidisk
The Minidisk Drive Case contains a
BASiC includes the standard functions of
disk drive, power supply, line buffers and
BASIC,
addressing circuitry. The Drive address
plus
maintenance
many
extra
procedures
file
that
is
switch
selectable.
The selected
programming
address is displayed on the front panel
The software driver for the
for easy identification. Write protect is
significantly
power.
increase
Minidisk Read/Write functions is based
on the hard
sectoring format,
which
simplifies system configuration.
The Aitair 8800b interacts with the
Aitair s y s t e m f e a t u r i n g 8 S O O b Turnkey M o d e l , d u a l Aitair M i n i d i s k s . LSI A D M - 3 C R T
a n d Q 7 0 Line Printer.
C / N J u n e . 1 9 7 7 ONE
Minidisk
also a standard feature on the drive.
Check with MITS or your local dealer
for prices and availability.
CONTtNUED
NEW ALTA)R <VH<N<D<SK
STORES OVER 71K
A D D H A R D COPV
CAPAB!LmES
CONTtNUED
88-MDS Attair Minidisk Controtter
Description
includes
Controller
Boards
and
Cables. Can controt
Drives.
Similar
operation
Bits per
interconnect
second
1 to 4 M i n i d i s k
in c i r c u i t r y a n d
to the Aitair
Controller.
2. Data Transfer Rate: 125,000
a s e t of 2
Ftoppy
Disk
First drive is included in
3. Access Time
a) Disk Enable to R E A D
or W R i T E (Function of
motor start-up t i m e ) :
MDS. Additional Drives are available as
88-MDDR'S.
lsec
(min)
b) Track to track:
50 ms
c) Average Access Time
Specifications
(including motor
Number of slots
start-up t i m e ) :
1.85 sec
3) Worst Case Access
required in 8800
bus:
2
Time:
2.9 sec
e) Worst Case Latency:
Number of ICs:
Functiona! Specifications
TTL Logic:
57
CMOS:
1
Voltage Regulators:
2
1. R o t a t i o n a l
Speed:
300 r p m (200
ms/Rev.)
2. Track Density : 48 tracks per inch
interconnect
3. Number of Tracks: 35
Wiring: Insulation displacement cables
4. Number of Sectors: 16
and connectors
5. Time Per Sector: 12.5 ms
i/0 Addresses
Software:
(Octai): 010, 011, 012
BAStC
Attair
Software
Data Transfer
Format: Hard
Minidisk
Extended
on a W r i t e
Protected
Minidiskette is virtually identical to
Rate: 1 byte every 64 us
Data
200 ms
Sectored
(16
Aitair
Disk
BASIC
in operation a n d
features. The manual includes Bootstrap
sectors)
interrupt
Listing and R E A D / W R t T E Drive Code.
System: Interrupt at beginning of sector
Be sure to specify the cassette tape or
(Optional
- not used for
Aitair Minidisk BASIC)
paper tape for Bootstrap
Power
Programmed
Requirements: 1.4A @ 8V
each):
88-MDDR Aitair Minidisk Drive
1. M D B L
Description
power
Disk drive in case with
supply,
Buffer
and Address
Loader, if
required.
PROMS
PROM.
Avaitabte ($45
Minidisk
Bootstrap
Loader on p r o g r a m m a b l e read only
memory iC to be used with 88-PMC
eiectronics. inciudes Interconnect Cable
P R O M Memory Card at highest 256-
and one biank Minidiskette.
byte block address.
2. D R W T P R O M . Floppy and Minidisk
READ/WRITE
Specifications
1. D a t a
Capacity
Format
— Hard
' .;
!
Sectored
. .
a) Per Minidiskette: 71,680
Data Bytes
b) Per Track:
fundamental
Test P R O M has the
diagnostic
tests for
checking hardware operation. To be
used with the 88-PMC at 3rd highest
256-byte block address.
2,048 Data
Bytes
c) Per Sector:
128 Data
Bytes
FOURTEEN
C/N June. 1 9 7 7
TO
VO^R
SVSTEM
peripherai
calcuiates the most rapid way to print
products-the C700 high-speed printer and
each tine so that unnecessary carriage
the Q70 printer-to interface with
returns are eliminated.
MiTS
returns a n d reducing wear.
introduces
two new
the
Aitair 8800 series microcomputers.
The Q70 operates with
The Aitair C700 is a high-speed seriai
'daisy
character printer which prints up to 60
lower case characters. The wheei spins
characters per second. The printhead is
for character iocation, and a h a m m e r
a 5X7 dot matrix which prints the 64
then forces the wheel against the ribbon,
character subset of the ASCii font.
paper and platen.
The Aitair Q70 is an upper and tower
Both the C700 and Q70 provide other
case/etectric typewriter-quaiity printer
superior features for easy operation with
speciaiiy
designed
and
modified
to
minimal maintenance. Each printer is
interface with the Aitair 8800 series, it
furnished
prints
case
accommodate forms up to 15 inches in
characters and symbols at 45 characters
width. An electronic Top of Form in the
per second.
Q70 provides rapid positioning of each
The
96 u p p e r
Q70
is
and
ideai
lower
for
business
with
also included.
any other application
and/or
which
requires
form
tractors
to
sheet. A manual Top of Form switch is
systems, word processing systems or
wheei
With the Q70,
ribbon
replacement
is not
messy
The
an
high quality printout for letters, iabeis,
exasperating,
documents, etc.
wheel is easy to replace, and the ribbon is
Each printer operates in a highiy
efficient yet unique manner. The C700
C/N June. 1 3 7 7
a
wheei' system to rapidly print upper and
task.
print
conveniently enclosed in a cartridge.
CONTINUED
FIVE
/yew
MMTS OFFERS TWO CRTs
By Bennett tnkeles
MITS now offers the LSI ADM-3 and
the Aitair
B-100 C R T t e r m i n a i s for
reliable communication
in any Aitair
computer system. Such user benefits as
fast,
quiet
operation
and fewer
mechanicai probtems are just some of
the
reasons
to
consider
CRT
implementation.
Both terminals display 24 lines of 80
characters on a non-glare screen and
interface at RS-232 and 20 m A current
loop levels.
standard
switch
A D D H A R D COPY
CARAB<L<T<ES
TO Y O U R SYSTEM
CONTINUED
Font: 96 character positions on 'daisy'
in 10 a n d 12 pitch.
applications.
proportional
Vertically
spacing in
in
Slew rate at 5 " per second.
centered character lines, the C700 has
Aitair C700 Specifications
increased throughput, since the print
Printing
absolute
minimum.
A circuit
serial,
impact, bidirectional.
Printing rate: 60 characters per second,
m a x i m u m ; 26 132-column
wear since parts motion is reduced to an
lines per minute.
which
allows power to be decreased when the
Transmission rate: 75,000 characters per
printer is inactive further reduces wear.
second (bit-paraltet,
character-serial).
Both printers are easily integrated
into any Aitair 8800 computer system.
Each
comes
with
Indicators/Switches: O n / O f f ,
tnternal
controls: Automatic
control,
complete the interface by connecting the
away
printer to the computer via the interface
Check with MITS or your local dealer
for prices and availability of the Q70 and
mm
second;
Full characters
writer quality.
continuous
multipart forms with or without
sprocket holes. M a x i m u m width
of 15 inches.
after
(17.3"). Up to 5-part
sprocket-fed
continuous
forms m a y be handted.
Dimensions: 178 m m high, 457 m m deep,
622
of electric typeor
feed
forms can be handled. Any
Print speed and format: 45 characters
sheets
auto
Paper feed: Tractor (pin-feed) up to 439
Aitair 88-Q70 Specificiations
F o r m s : Single
p a p e r run-
carriage return.
C700.
per
motor
inhibitor,
tine
board.
mm
wide.
(7"x28"x24.5")
RS-232
permanent
copies can be easiiy
The Aitair
B-100 inciudes
quad-
directional cursor control with carriage
cursor for direct positioning by tine and
column,
11-key n u m e r i c
decimal
point
pad with
for s i m p i e
e n t r y of
numeric data, erase mode for cursor to
end of line and cursor to end of memory
erase.
A!tair 16K Memory
Board N o w Avai<ab<e
The new Aitair
memory
module
provides 16K bytes of d y n a m i c Random
Access Memory. By implementing low
power and fast access dynamic memory
ICs, the Aitair 88-16MCD runs at a
maximum
watts
power
dissipation
and a m a x i m u m
of three
time
of 350
nanoseconds.
Crystal-controlled
logic
timing
eliminates the need for on-board one-shot
multivibrator circuitry. This resuits in
continuous operation without wait states
for greater reliability.
Bus strips provide isolation between
Weight: 27 kg (60 lbs.)
Electrical
system
The ADM-3's
retained.
Out Indicator,
interface card which is ptugged into the
Aitair bus. Ribbon cables and connectors
Select/
Deselect, Paper/
its o w n s p e c i a l
features
of
return and tine feed, an addressable
method: Character
head returns to the right or left margin.
unique
to asynchronous serial ASCI) printers so
that
— spacing
many
for a variety
extension connector permits interfacing
Increments of 1 /48" up or down.
less t h a n 132
This special feature results in minima)
include
unit.
Format: Horizontally — 132 characters
rates
The LSI ADM-3 and the Aitair B-100
also
suitable
increments of 1/120".
set to print
character set and
selectable transmission
Prestige Elite comes with each
and
When
C R T includes the
from 75 to 19,200 baud.
print wheel; wide variety of fonts
available
Each
64 ASCII
requirements: 115/230 VAC
+ 10%,
Hz
50/60
power and signal tines for m a x i m u m
noise suppression. Address setection is
switch
selectable in 4K biocks.
Each
board requires one stot on the Attair 8800
bus.
C / N J u n e . 1 9 7 7 ONE
The Aitair B - 1 0 0 C R T p r o v i d e s f a s t , q u i e t a n d efficient o p e r a t i o n f o r a n y
Aitair c o m p u t e r s y s t e m .
Publications Offer
Variety of Approaches
The
April
issue of
COMPUTER
NOTES featured an article
"Publications
Provide
entitled,
Novice
With
COMPUTER
to that of PCC, but information is aimed
hardware/software
at advanced computer users. Software
PEOPLE'S
COMPANY
is a
applications-oriented
tabloid
for the
articles, such as games, modifications
Essential Information," (Page 10 M a y
novice a s welt
as the experienced
and unique software systems, make up
CN),
some of the current
computer user, information is presented
the bulk of D D J . Product releases and
computer iiterature. We regret that the
in an informal style with m a n y useful
reader
following
annotations. PCC also acts as a sounding
informative magazine.
surveyed
publications from
People's
Computer Company were not Included.
board for novel ideas proposing changes
in computer technology.
The
format
JOURNAL
of
Dr.
OF COMPUTER
DOBB'S
CALiS-
T H E N i C S & O R T H O D O N T I A is similar
responses
COMPUTER
round
out this
MUSIC
JOURNAL
offers a c o m p r e h e n s i v e
a n d highty
technical
approach
musical
applications
to high
of
quality
digital
electronics. This journal is best suited for
those who utilize theoretical information
for designing computer music systems.
Subscriptions
and
additional
information about these publications can
be obtained f r o m :
People's Computer Company
P.O. Box E
Menlo Park, CA 94025
C/N June, 197 7
SEVEN
A
d
d
s
V a r s a t i ^ i t y
t o
A ! t a i r
By Dave Antreasian
S y s t a
The graphics capability of a CRT
plays
an
important
r o l e in
every'
computer system. The graphics mode is
especialiy useful for displaying graphs or
curves quickly
in reai-time and
is a
" m u s t " for such computer games as
Ping-Pong.
The foiiowing program was written
for
these
applications.
hardware
restriction
versatility,
the program
mode!
for any
hardware
system
restriction
Although
limits
is a
a
its
heipfu!
display.
The
refers to cursor
control incompatibiiity with
terminals
that include this feature.
This p r o g r a m
was written for a
Beehive 100 terminal, in which the cursor
is positioned by sending the following
four-byte code to the terminal:
(ASCII)
Octal Code
(ASCIi)
Decimai Code
Byte 1. Escape Sequence Code
33
27
50
40
3. Line Number
40-64
*32-54
4. Column Number
40-157
"32-111
2. Cursor Address Function Code
*32 Represents line o r c o i u m n 1;
33 Represents line or column 2, etc.
This four byte sequence positions the
cursor, and the next byte received prints
the desired
character.
Notice
that
positioning the cursor beyond either field
limit causes the cursor to disappear or
scroll the display.
If the display
is
BASiC.) Each point in the
data
screen
parameters:
properly,
because
the
first
" h o m e " reference point will be tost.
The program
BASIC
with
is written in Aitair
a user-cailed
Machine
Language display routine at tine 5000.
Although it would be more efficient in
machine language, its versatility would
be greatly reduced in the translation.
The program accesses an Anatog-to-
block
is s p e c i f i e d
by
three
1. the first byte is the tine number
(ASCii)
2. The second byte is the coiumn
number (ASCIi)
3. The third
byte
is the
desired
character (ASCil)
Notice
that
the
data
block
is
composed of two sections. The first
Digita! Converter card (88-ADC) which
section
reads eight channels of information and
for " m o v i n g " data points, and the second
thus defines four points on the display. A
section
fixed
sections are separated by a data byte =
background
"fieid"
is
also
dispiayed.
By substituting another subroutine
FOURTEEN
initialing
scroiied, the program cannot blank the
(bytes8064to8075)
contains
"fixed"
is reserved
points.
The
255. Upon recognition of the (255) code,
the display program jumps back to the
for the one at line 7100, Aitair BASIC can
BASiC program, so the " f i x e d " field is
plot any number of desired points simpty
dispiayed
by writing each point into the " D a t a
"moving"
Btock," which starts at iocation 8064. (Be
display. This significantly reduces the
sure to limit memory size to 8000 when
display writing time.
oniy once. Then oniy
fieid
is refreshed
to
the
the
C/N June. 1977
Machine Code Portion of
Display Routine
LIST
037, 100
41
103 315 Call Status CK?>
104 [ 1 6 6 1
105 L037 J
106 176
133
107
110 323
111 023 Call Status CK. \ Cursor
112 315
/ Address
113 j-1661
114 L037 J
115 076
116
117
120
106
323
023
001
121
LXI (B,C)
122 r o o o i
123 Looo J
160 L110 J
323
161
162 023
Next Data point
163 303
164 [-1031
165 L037 J
166 333
167 022 *
170 037
171 037
( Status
172 322
f Check
173
174 L037]
175 311
176 0
177 0
200
1st Data Loc.
C/N June, 1 9 7 7
,,
,,
,
,
0
124 315 Call Status CK.
125 r i 6 6 1
126 L037 J
127 176 ACC MEM
130 376 CPI) test byte
)
131 377
132 310 RET if Zero
2j Output
133 323
Output data
134 023
, 135 043 INCR H.L.
136 003 INCR B.C.
137 076 j (ACC) 3
140 003
141 271 CMP ACC to (
142 302 JNZ
143 ri241
144 L037J
145 315 Call Status
146 r i 6 6 i
147 L.037 J
150 076
151 033
152 323
153 023
154 315 Call Statusi
Cursor
155 r i 6 6 i
Home
156 L037 J
157 [-0761
* Port 2/RS232
2 PPIi'jT"'HO! 1)Ei..ETE L I K E S S - 6 0 A rir. P E - P r n "
31
3 3 : P O K E 800 1 , 1 2 8 :POK;E 8 3 3 2
10 POKE 80 0 0
12 POKE 80 3 3
lit
:POKE 83 0 5 , 31
2 0 5 : P u K E 8 3 34
62 :POKE 83 3 7 , 2 7 :POKE 80 3 8 , 211
14 PO HE 80 0 6
11 8
16 POKE 80 0 9
! 9 :POKE f 3 1 a , 20 5 :POK.E ^ 0 1 1
18 POKE 80 12
31 :POKE 801*3 , 62 rPOJ'.E 80 14 , 70
21 1 :POK E 8 0 16
19 :POKE 80 17
1
20 POKE 80 1 5
28 POKE 83 1 8
0 :POKE 80 19 , 3 :POKE 8 3 2 3 , 2 0 6
12 6
1 1 8; :POKE 8 a 2 2
31 :POKE 8 0 2 3
24 POKE 80 2 1
26 POKE 80 2 4
2 54 :POK E 8 0 2 5
2 5 5 :POKE 8 0 2 6 , 2 0
28 POKE 80 2 7
21 1 : P o K E 8 0 2 8
19 :POKE 8 0 2 9
35
30 POKE 83 3 0
3 :POKE 8 0 31 , 6 2 : p O K E 80 32 , 3
32 '^OKE 80 3 3
- 1 9 4 :"-'OKE 8 0 3 5 , 84
1 8 5 :POK E 83 34
34 POKE 8 03 6
31 {POKE 80 3 7 , 23 5 :POKE 8 0 3 8
11 8
36 POKE 8 0 3 9
31 tPOlfE 83 40 , 62 : " 0 K E 8 0 4 1 , 2 7
38 POKE 80 42
21 1 :POH, E 83 4 3
19 :POKE 8344.
20 5
40 POKE 80 4 5
1 1 8 : ^ O K E E0 4 6
62
31 :POKE 8 0 4 7
42 POKE 80 48
72 :POKE 8 0 4 9 , 211 : P 0 K E f 0 50
1 9
44 POKE 80 51
67 :POKE 8 3 53
1 9 5 :POK E 80 52
31
46 POKE 80 54
2 1 9 :POK E 80 5 5
18 :PUKE 80 5 6
31
48 POKE 80 5 7
31 :POKE 8 3 5 8 , 2 1 3 :POKE 8 3 59
1!8
50 POKE FQ 6 3 , 3 1 : P C K E 8 0 61 , 2 0 ! :POKE80 6 2 , 3 : P O K E 8 0 6 3 , 0
60 STOP
70 V l - t O : E I A S = 0 : D t = d 5 : M = 6 6 : E 3 = 6 7 : I ; A = 6 € :ST=i?0 64
80 0!.*T13 0 , 0 : O P T 1 3 1 , 2 5 5 : O H T 1 3 0 , 4 : O P T 1 2 8 , 0 : O P T 1 2 9 , 2 5 5 : O P T 1 2 8 , 4 4
90 0 K T 1 3 4 , 0 :OPT 1 3 5 , 0 :0UT1 3 4 , 4 :01 T1 3 2 , 0 :0!.'T1 3 3 , 0 : 0 P T 1 3 2 , 4
100 0 P T 1 9 , 2 7 : 0 ! * T 1 9 , 6 9 : P E t . PLAN!! D I S P L A ^
150 FOUI-PO 64T0 92 6 7 ' : P 0 K E I , 32 :KE T I
200 P O K E 7 3 , 6 4 : P ' 0 K E 7 4 , 3 1 : P E ! - SET t: -=80 3 3
10 0 0 FOP 0 = 8 3 79 TO 9269:t.OSPP.&aOO
NEK
50 0 0 :*=!*SP ( Y )
550 0 0 H T 1 9 , 3 2 : 0 P * T 1 9 , 3 2
570 0 P0KE8O 7 6 , 2 5 5 ! P O K E 6 3 7 7 , 2 5 5 : P O K E 8 Q 7 8 , 2
61 0 0 I F P ! i E i ; ( e 0 6 6 ) = 3 8 Tl-BH 650 0
62 0 0 POi:ESO 6 6 , 3 2 : P 0 K E 8 Q 6 9 , 3 2 : P O K E 8 3 7 . S S t P O h E e O 7 5 , 3 :
62 5 0 GOTO 530 0
650 0 8 0 S P B 7 1 3 0
651 0 POKE83 6 4 , L I + 3 2 : " 0 K E 8 3 6 7 , L 2 + 3 2 : P O K E 8 3 7 0 , L + 3 2 : P O K E f 0 7 3 , L 4 + 32
6530 POKBCO 6 5 , C I +32 : P O i ; E 8 3 6 8 , C.2 + 32 :POKE8 3 71 C3 + 32 :POKE8 0 7 4 , 0 4 + 32
6 5 4 0 POKE&O 6 6 , D 1 : P O K E 8 0 6 9 , D 2 : P O i : E 8 0 7 2 , P 3 : ^ O K E 8 0 7 5 , D 4
70 0 3 LOTu 50 0 0
71 0 0 FOP CH = 0 T 0 1 : O P T 1 3 1 , C H : O P T 1 2 9 , C K
72 0 0 MS = H'jP (1 33 ) : L S = I i ' P ( 1 3 5 )
73 0 0 V= ( (1 6*t;s + ( ( L S / 1 6)AND1 5 ) ) * V I / 4 0 9 5 ) - E I A S
73 50
740 0 I F Cl!=0 TP EH L I = I N T ( V )
741 0 IF C ! = l THEN C l = I i J T ( 4 * V )
742 0 I F CH=2 THEH L 2 = I N T ( V )
7430 I F CK^3 T!:EK C 2 = I N T ( 4 * V )
744 0 I F CP = 4 THEH L 3 = I U T C V )
74 50 IF CK = 5 THEM C 3 = I N T ( 4 ^ V )
7460 I F CH=6 THEN E 4 = I H T ( V )
74 70 I F Cl;= 7 THEN C 4 = I N T ( 4 * V )
7650 N H ' T CH:RETt'P.N
80 0 0 READ X : I F X=2 5
THEN POKEJ,>::C-OTO 50 0 0
80 0 2 RETURN
850 0 D A T A . 3 5 , 3 5 , 4 3 , 3 6 , 3 6 , 4 3 3 7j 3 7 , 4 3 , 3 8 , 3 8 , 4 3 , 3 9 , 3 9 , 4 3
8501 DATA 4 0 , 4 0 , 4 3 , 4 1 , 4 1 , 4 3 42. 4 2 , 4 3 , 4 3 , 4 3 , 4 3 , 4 4 , 4 4 , 4 3
8502 DATA 4 5 , 4 5 , 4 3 , 4 6 , 4 6 , 4 3
8590 DATA 2 5 5 : R E K END OF B L O C !
OK
,
LX1M
101 [200]
102 L037_]
,
,
,
,
,
,,
,
,,
,,
,
SOFTWARE
NINE
SOFTWARE
NOTES
User s Program
Handtes Compter Numbers
By Chuck Vertrees
By John Hayes
Complex numbers often appear In
Genera! Manager, ASDC
scientific and advanced
Program improvement
and improving
programs in the User Group
A complex number is defined as a
number that has both real and imaginary
calculation,
in order to use complex
parts,
numbers,
the reader
first
rectangular form as A + iB where A is
t h e 300
understand
the concept of imaginary
the real part and B is the imaginary part.
Library.
numbers.
The Aitair User Group is currently
reviewing
mathematical
An
Many of the programs will be put in
must
it is u s u a l l y
represented in
It is considered as one quantity when
imaginary
number
is a real
doing
calculations.
For example, the
machine readable form and grouped for
number muitiplied with an imaginary
numbers (1) 3 + p and (2) 4 -
a particular size computer and language.
operator.
rerpesented in graph 2.
(The imaginary operator is
Single programs will still be distributed
usually represented by an " i " or " j . " )
in whatever form
This operator
they are received.
is defined
so that the
Current software listings (printed every
square root of minus one is equal to the
month
operation, i.e.4-1 = i, or ( i ) ' = -1 or i x i
in C O M P U T E R
NOTES and
supplied as a separate update sheet to all
= -1. Remember that the square root of a
CN subscribers) will show hardware and
negative number is not usualiy defined.
language
With the above definitions, the square
requirements
for each
roots of n e g a t i v e
program.
numbers
680b),
Notice that (3)' = 9 and (-3)' = 9. But
program's
memory
3+
and the
requirements in
.0)
21-5
= 13.
used
4
represented. For e x a m p l e , ^ 9 l = 3 a n d f ? - R f — I — I — I — h
When submitting a program, users
the language
s-t-
2.
c a n be
should indicate the computer (8800 or
are
-4
-3
-2
-1
-+R
-+—t-1
(2)
-2
(i3)' = -9 and (-i3)' = -9.
bytes.
Graph
1 represents
-3
imaginary
numbers should clarify the difference
Price increase
between imaginary numbers and real
-S
numbers. Remember that it is possible to
Rising costs of program duplication
graphically represent a function in two
-l
Graph 3 shows polar form as an
dimension by drawing an " x " and " y "
alternative
prices for some programs. Program and
axis and then
complex number. Notice that the point 4
subroutine listings are now $4 for up to 10
function.
pages, $5 for 11-20 pages and $6 for 20-40
(1) ( X , Y ) = (2, 2)
(magnitude and angle), which is written
pages. These new prices are indicated on
(2) ( X , Y ) = (4, 3)
as L-&
the listings in this month's CN insert.
(3) ( X , Y ) = (-2, 2)
Price changes for all previous programs
(4) ( X , Y ) = (3, 0)
have resulted
in a slight increase in
plotting
values of the
method
of representing a
+ j4 can also be represented as a vector
will be issued as an appendix to the AUG
(4, i 4 ) or
+y
Software Catalogue.
5 1.
4 -
Machine-readabie code
3 -
The User G r o u p is interested In
programs
already
in the
library. Anyone who can provide the
:
)
S
)
1
.4
User Group with either paper tape or
cassette
forms
of earlier
1
-2
i
-1
-2-
Library,
-3-
343, 3330
t^R
(4) !
- l
programs
should contact the Aitair User Group
Suite
i
l M 1
software
!
(1)
J
purchasing machine-readable code for
.(2)
Peachtree,
Atlanta, Georgia 30326.
-4-
in
- 5 --y
In this case both the X and Y axis are
TEN
graph
(rectangular)
3 the point
is represented
4 + i4
as the
length L from the origin at ang!e-&-where
real number lines. Now, let's replace the
L =</ X ' + Y? = V 4 ' + 4' = / 3 2 * = 4^5* and
real Y axis with an imaginary " i " axis so
tan O- =4/4 or-&= arctan 1 = 45° which is
that the Y axis represents imaginary
represented in Standard Polar Form as
numbers.
C/N June, 197 7
The following compiex number flow
chart and
program
written
in
Aitair
BASiC is avaitabte through the Aitair
Compiex Number intrepreter for BASiC
By Dr. John J . Herro
(Used as a Program or Subroutine)
Annotated Program Listing
User Group Software Library.
mainprgm.
49990 L Z = 0 : iNPUTSS: GOSUB 50010: GOTO49990
(AUG Library number: 7014)
subroutine
50000 L Z = 1
50010 S Z $ = " ( ?+-*/ % ! D R P E L " : i F S S = " " T H E N R E T U R N
50020 FOR J Z = 1 TO LEN (S$): GOSUB50030: N E X T J Z :
RETURN
50030 F O R )Z=1 TO 16: ) F M i D $ ( S S , J Z , 1 ) = M I D $ (SZ$,
IZ,1) THEN 50050
badchar.
50040 N E X T iZ: P R ) N T " U N R E C O G N i Z E D C H A R A C T E R i N " :
good char.
50050 ON iZ GOTO 50070,50290, 50240, 50220,50210, 50270, 50260,
GOTO 50170
50300
50060 ON iZ-8 GOTO 50200, 50190, 50280, 50330, 50120,50320, 50150:
RETURN
(
50070 F O R ! Z = J Z T O L E N ( S S ) : i F M I D $ ( S $ , i Z , l ) = " ) " T H E N
missing )
50080 N E X T iZ: P R I N T " M i S S i N G ) i N " : GOTO50170
)
50090 A Z = V A L ( M i D $ ( S S $ , J Z + D ) : E Z = 0
50090
;
50100 FOR K Z = J Z TO iZ: iF M ! D $ (S$, KZ, 1) = " ; " THEN
E Z = V A L ( M i D $ (S$, KZ+1))
50110 N E X T KZ: J Z = I Z : R E T U R N
P
50120 iZ=1.570796*SGN(EZ). i F A Z T H E N i Z = A T N ( E Z / A Z )
50130 t F A Z 0 T H E N iZ = iZ+6.283185*((EZ 0)+.5)
50140 A Z = S Q R ( A Z 2 + E Z 2): E Z = i Z : R E T U R N
L
50150 GOSUB 50120: i F A Z T H E N A Z = L O G ( A Z ) : R E T U R N
aritherr.
50160 P R i N T " L O G ( 0 ) O R / O O R O ( X ; Y ) , X
error
50170 P R i N T S U P R t N T T A B ( J Z - l ) "
=0iN"
"
50180 iF L Z T H E N E N D E L S E J Z = L E N ( S $ ) : R E T U R N
!
50190 i Z = A Z : A Z = B Z : K Z = E Z : E Z = F Z : GOSUB 50230:
D Z = i Z : H Z = K Z : RETURN
%
50200 i Z = A Z : A Z = B Z : B Z = i Z : i Z = E Z : E Z = F Z : F Z = ! Z : R E T U R N
50210 AZ=-AZ: E Z = - E Z
+
50220 A Z = B Z + A Z : E Z = F Z + E Z
drop stack
50230 B Z = C Z : C Z = D Z : F Z = G Z : G Z = H Z : R E T U R N
?
50240 PRiNTAZ;CHR$(43-(EZ 0 ) * 2 ) " I " A B S ( E Z ) : GOSUB50120
50250 P R ) N T " = " AZ " A T " EZ*57.29578"DEG.": GOTO50330
/
*
50260 GOSUB 50150: AZ=-AZ: E Z = - E Z : GOSUB 50320
50270 iZ=AZ*BZ-EZ*FZ: E Z = E Z * B Z + A Z * F Z : A Z = i Z :
GOTO 50230
D
50280 EZ=EZ/57.29578: GOTO 50330
50290 D Z = C Z : C Z = B Z : B Z = A Z : H Z = G Z : G Z = F Z :
F Z = E Z : RETURN
50300 )F B Z = 0 A N D F Z = 0 A N D A Z 0 T H E N A Z = 0 : E Z = 0 :
GOTO 50230
50310 GOSUB 50200: GOSUB 50150: GOSUB50270
E
50320 A Z = E X P (AZ)
R
50330 ! Z = A Z * C O S ( E Z ) : E Z = A Z * S i N ( E Z ) : A Z = i Z : R E T U R N
NOTE: Spaces were inserted in this program listing to improve readabiiity.
Deieting ail unnecessary spaces will save 149 bytes. This program was written in
Extended BASiC. it will run in 8K BASiC If line 50180 is replaced with:
50180 iF L Z T H E N E N D
50185 J Z = L E N ( S $ ) : R E T U R N
A 30-page user manual is availabie for $6 from the Aitair User Group Software
CONTiNUED
C/N June. 1S77
ELEVEN
R
e
s
e
q
u
e
n
c
e
s
L < n e s
P
r
o
g
r
a
E v e n t y
m
K
i
n
c
e
r
e
e
p
m
s
e
n
t
e
d
By Doug Jones
in
is the largest possible line n u m b e r that
BASiC, the first few iine n u m b e r s a r e
Whenever
i write
a program
680 BASIC will accept without displaying
half-way
aiways nicely incremented — 10, 20, 30
an error message.
suddenly show an error message. For
etc. The subroutines also start a t easy-to-
How to Use t h e Resequencer.
r e m e m b e r line numbers, such as G O S U B
Write
or load
your
Sometimes the resequencer might be
example,
program
through
a
the newiy
program
sequenced
240 IF A = B T H E N G O S U B
1000. But things don't seem to stay that
containing the odd line numbers. Then
remark
load the resequencer and type in the
E R R O R O N L i N E 473
explaining w h a t the routine is about a n d
starting line — RUN63967. After a few
OK
have to squeeze in 999REM. By the t i m e
seconds, t h e computer will a s k :
the
O L D LINE, NEW, STEP, NULLS?
program
t o p u t in a
is c o m p l e t e ,
t h e line
listing
might print the following message.
nice,
i forget
and
The line n u m b e r referenced to in t h e
error message is in the original p r o g r a m .
numbers look anything but weli planned:
Y o u r answer m i g h t be 7,100,10, 5. This
This can occur
10, 16, 17, 33, 49 . . .
indicates
asked to resequence a line that does not
The following resequencer p r o g r a m
gives
Aitair
680 B A S I C
professional-looking,
( ! ) your
old p r o g r a m
if t h e resequencer is
began at line 7, (2) you w a n t to renumber
exist.
it starting with line 100, (3) in increments
How Does the Resequencer W o r k ?
users
evenly
that
Resequencer
of 10 a n d (4) set N U L L S to 5.
incremented lines. The user m a y choose
Resequencer
does
not r e w r i t e a
the starting line n u m b e r a n d the step of
program
in m e m o r y .
increment.
produces
a
typed
Instead,
listing
it
property
runs
through
a
p r o g r a m three times. The first t i m e it
looks for the first O L D line
. When it is
found, the system examines the p r o g r a m
specifications.
line by iine, counting lines as it goes. It
only 33 iines long. I intentionally wrote it
With this listing and a punched tape, the
stops when it reaches its own first tine
in unusual line numbers. To avoid being
user can type N E W and then re-enter the
number.
a 'space' gobbler, the p r o g r a m lines a r e
newly sequenced p r o g r a m .
The B A S i C resequencer p r o g r a m is
sequenced to t h e users
t h e second
On
pass
it
gathers
existing line numbers into a n a r r a y for
incremented by one. The last line, 63999,
User s Program
HatltcMes Complex Numbers
CONTINUED
60090
(
START
PRINT
ERROR
MSG.
NOT
50070
FOUND
D
60020
(
N/
RETURN
FIND NEXT )
CHAR.
N
CHAR. = ? ?
OMR.
50240
50290 ,
# ?
FOUNO
50090
PUT FIRST N O .
(OR ONLY NO.)
INTO REAL PART
A T BOTTOM OF
STACK, 0 tNTO
IMAG. PART.
j
Y
PRINT
REAL &
IMAE
PARTS.
CHAR. = - ?
RAISE
STACK
50] 00
CHAR. = / ?
CALL
LOS
NEGATE
BOTTOM N O .
ON STACK.
CALL
EXP
IS THERE ;
CALL
POLAR
50300
CHAR. = t ?
BASE = 0 &
REAL (EXP0N)
>0 ?
PUT 2ND NO.
INTO IMAG PART
AT BOTTOM OF
STACK.
50310
INTERCHANGE
Z] AND Z,.
! o
CALL
LOG
)
50320
PUT 0 ON
BOTTOM OF
STACK.
FOURTEEN
CALL
MJLT
CHAR. = * ?
WITHIN ( ) ?
* 180/"
NESATE
BOTTOM M 0 .
ON STACK.
50260
N /
PRINT M A E . , a
ANGLE (RADS)
DROP
THE
STACK.
50270
50210
ANY MORE
CHARACTERS
IN STRING?
A00 BOTTOM
2 N0S. ON
STACK
CHAR. = + ?
CALL
EXP
CALL
MULT
C/N June. 1 9 7 7
LI SI
future G O T O and G O S U B references.
Resequencer displays the n u m b e r Ojf
lines the p r o g r a m contains. It tetls the
*+ + * * O E M O N S t i ^ t l O N
I TNPUi o
17 IF
[PEN 49 3
A3 IF a=C 1 wgN GOSUB ] :
SI 0\ A GOiO ] . 3 7 , 4 9
77 GOSJB t : G O i 077
"3*1 G )I 3 ]
OF nESEOJENCErt r'rfOGnAM
*****
user to R E A D Y P U N C H and then pauses
white
the
Starting
operation
leader
and
is
performed.
contro)-0
are
punched a u t o m a t i c a i l y to prevent echo.
On
the third
pass, t h e
program
begins listing. E a c h initia) line n u m b e r is
639 67 0^1 -<\END,FOR,MEXi
T<
HJ\63?6 7
*).[) LINE A, NER
' 1 \!E S = 7
^KADY P!J\CH
S)EP,
A, INPOt
,G0< O . r t L ^ , IF,rtES< One.
\JLLS?
the incremental step f r o m the previous
tine number. Referenced line n u m b e r s
are
then
a function
of the
starting
p a r a m e t e r s and the position of a
iin!
n u m b e r in the a r r a y .
The resequencing and
iisting
stop
when the p r o g r a m reaches its starting
iine n u m b e r . It then resets nulls to zero,
prints an E N D to undo the control^) echo
suppression and spiils out some finishing
tf* REM * * * * *
p7l t ^ i p j i 4
IF
DEMONSIfsAIION
OF KESEGOENCE^
*****
7?l
IF
3=C
GOSUB
4 G U I ?7t,
GOSU^ P 3 : G 0 < ) 6 ^
71 GOTO 23
P9:
ieader.
Since resequencer starts looking for
the old first line
in the top part of
K
CONTtNUED
BASiC, there is a siight chance that it
)
MULT
50200
^
CHAR.
=
%
50270'
USE
?
(U;Z)*(X;Y)=
(WX-YZ;WY+XZ)
N
^
CHAR.
=
:
DROP
?
THE
STACK.
N
RETURN
CHAR.
D ?
50)50
]
]
f P O L A R
CALL
LOG
S0120
CONVERT
FROM
RECT. TO
POLAR FORM
(ANGLE IN
RAOS),
SELECTING
PROPER ARCTAN.
CHAR.
N
CHAR. = BLANK ?
C/N
June,
1977
50040
PRINT
ERROR
MSG.
(
RETURN
D
RETURN
SEVENTEEN
J)
J
Circuit Ana!ysis Applications
Expanded t o Run w i t h Aitair BASNG
Mew PoHicy
. A d o p t e d
Due to rising costs, M I T S will now
oniy
accept
A circuit is a group of components
orders for $25 or more.
with fixed characteristics interacting in
Please place all other orders with your
some prescribed m a n n e r . A n electricai
local dealer.
engineer's
job
is
to
deveiop
m a t h e m a t i c a i reiationships between t h e
R e s e q u e n c e r
K e e p s
P r o g r a m
An optional old starting line n u m b e r
L i n e s
further
Ewarn^y Encremented
CONTtNUED
into
a program
will
permit
of a circuit
describe
the total
behavior
network.
In order
to d e v e l o p
that
of t h e
these
resequencing of a latter portion of t h e
relationships, electronic circuits must be
p r o g r a m . This works as long as there is
anaiyzed.
no previous reference to the earlier part
m i g h t find some assembled instruction
of
with the s a m e
resequenced.
n u m e r i c value as the
various components
starting line n u m b e r . However, I haven't
the program
The
that
is n o t b e i n g
Computer
anaiysis
of
eiectronic
circuits is nothing new in itseif. However,
this p r o g r a m brings a u t o m a t e d anaiysis
user
can increment
the line
to the Aitair computer running B A S i C . it
seen it happen yet, and I've used the
n u m b e r s by any step, even 3.2 or -9.7. Ail
is, therefore, inexpensive to i m p t e m e n t
p r o g r a m to resequence everything I can
GOTOs
and easy to modify for speciai needs.
find on a paper tape.
correctly to line
a n d G O S U B s a r e referenced
437.13. Unfortunateiy,
The anaiysis technique a n d output
Attair BASIC will not run a p r o g r a m with
f o r m a t s used in this p r o g r a m a r e based
find the starting line n u m b e r — iust a bit
iine n u m b e r s tike that. W h a t can be done
on those in t&M's E C A P
longer if the trigonometric functions a r e
with such a listing? if you have a time-
Circuit Analysis P r o g r a m ) , written for
initialized in BASIC. Even if the oid first
share computer access a t work, give it to
the I B M 1620. The input f o r m a t is siightly
line n u m b e r doesn't exist, it will try its
the time-share coordinator. Teit h i m or
different than E C A P ' s . Aithough E C A P
darndest to find it a n y w a y .
I've seen
her: " L o o k w h a t your time-share has
does t h r e e d i f f e r e n t types of c i r c u i t
those lights blink for a half-hour, and it
done to all m y computer files . . . now
analysis, this p r o g r a m does only steady
still wouldn't give up.
none of t h e m r u n ! "
state D.C. anaiysis.
It usually takes only a few seconds to
(Eiectronic
The soiution technique used is nodai
^ L L 5 : F 0 K N = I i 0 ] 13 : ? C H R K P ) : :NEXt : ?CHx$( I 5 ) : L I S t
anaiysis. it's based on Kirchoff's current
iaw, which says the algebraic s u m of the
63 9 6 7
D A I A E N D , F 0 R , N E X 1 , D A t A , I N P U 1 , D I M , R E A D , L E i , GOt 0 , R U N , ! F , h E 3 t OHE
W 6 P
D A IA G 9 S U S , R E I J R N , R E f . , S I O P , O N , N U L L , W A I t
6*19 6 9
D A t A L I S I , C L E A R , N E W , t A h ( , t 0 , F N , S P C ( , i H E N , N O t , 5 t E P ,+ , - ,
^-1071
OAt A A N D , O R , > ,
619 7 !
DAIASIN.lAN,At N,PEEK,LEN,SiRt,7AL,AbC,CHR$,LEr
W 7 9
, D E F , P C < E , P R t N i , CO\ti
=-, < , S G N , I ^ i i , A 8 b , U S R , F r . ' E , P 0 S
*
,
zero, and O h m ' s Law, which says voltage
t
,MNt),L0G,EXP,C0b
!S,KIGHi
currents ieaving (or entering) a node is
MIDi
READC!:TFC!<>"END"tHEN63972
equais the product
current.
Apptying
current
Law and some
matrix
63 9 7 3
DIMAf ( 6 5 ): F 0 R N = i n 6 5 : R E A D A K N ) :NEXt : C =0:P=6)4 2 : Z = ] 2 7 : Y =63967
law,
43974
INPUf'OLD
alegbra, a computer can find the soiution
639 7 5
P ) = P : I F 0 L < > 2 5 6 * ( P E E H ( P + 2 ) ) + P E E K ( P + 3 ) i H E N P = P + ] : GOt 0 6 3 9 7 5
tTNE
# ,
NEW
S1EP, NULLb"!
OL,NI*,!B,M:AS(0)*"END"
63976
I F 25 6 * ( P E E K ( P +2 ) ) ^ P E E K ( P +3 ) = Y t W E N P R l N t " L I N E S
63 9 7 7
P=((2 56*(PEEHfP)))+PEE^(P+))):C
63 9 7 8 P R I N t " R E A D Y
639 7 9
= " : C : GOt 0 6 3 9 7 8
NULL ( M ) :F0Rt< : ] t O I 0 P ) : P R I N t C H R K 0 ) !
of a circuit after a description of t h e
circuit is in m e m o r y .
I : G 0 i 0639 76
PUNCM":FORK =1t 0 5 : P R I N t : N E X ) : F O R K
Ohm's
of resistance a n d
Kirchoff's
=1i O ] 0 0 0 : N E X t
Circuits a r e a series of nodes or
:NEXi :PRINt CHRK I 5 ) : P R l N t
63 9 8 71 D t ^ A ( C ) : P =P I : F O R N = ) f O C : A ( N ) =r( ( 2 5 6 * ( P E E K ( P ^ 2 ) . ) ) + P E E K ( P + 3 ) )
piaces
639P]
together a n d branches or connections
p=((2^6*(PEEK(P))
)+PEEK (P+ t ) ) : N E X i N : L L
C =0 : C t r " " : p = p ]
639 8 2
I P C r L L t W E N P R I N t " E N D " : N U L L 0 : F O R N =1 t O j 0 : P R I N t C H R K 0 ) : : N E X t : E N D
639 8 3
P P = ( ( 2 5 6 * ( P E E < < ( P ) ) ) + P E E K ( P + I ) ) : P =P + 2 : L N = N * +
639P4
PR I N t R IGWt S ( S I R K L N ) , L E N ( b t R K L N ) ) - ] ) !
639^5
6398 6
63907
"
(IB*C)
" ! : C
1 : P = P +2 : G O t
063986
8t HEN63990
TFF=Pti H E N P R I N t : P R I N i C I - : R K F ) ; : P : P + t : GOt 0 6 3 9 8 2
PR I N t C l - ' R K F ) ! : G O T 0 6 3 9 8 5
63 9 9 ^
p - p + ] ; G ^ P E E K ( P ) : I F G > = 4 8 A N D G < = 5 7 i H E N C t = C $ + C h ' R K G ) : F L =1 : G O t 0 6 3 9 9 0
TFG=3?ANDFL=atHEN63999
6399P
IFFL=]ANDG<7twEN63996
639 9 3
IFF<>!58ANDG<>0tWEN6399'i
63994
F=G:60I063986
63 9 9 5 P R T N t : P R I N t " E R R O R
63997
between the nodes containing electronic
components, i n p u t of the circuit to t h e
IFF>7tWEN63985
639cp
639 9 6
a r e connected
P=P+]:IFP=P2tHEN63982
F = P E E K ( P ) : I F F ^ Z I M E N P R I N t A K F - 1 2 8 ) : : I F F =1 3 6 0 R F = ] 4 0 O R F
639C9
6399!
where things
F O R K - ] t O L L : TFA( K )
ON U N E
#"}A(C):NL)LL0:END
( C 5 ) t H E N X t = S t R K N w t ( I B * ( K - ] ) ) ) : GOt 0 6 3 9 9 8
NEXIKrGOi063995
639QC
PR I N t R !GWt t ( X $ , L E N ( X i ) - )
63999
PRINtCHRS(6l!:G0i06399H
) : : FL=P): C i
I F G < > 3 2 A N D G < > 4 4 t HEN6 3 9 9 4
K
FOURTEEN
C/N June. 1 9 7 7
program is in terms of these branches
and their nodes.
The arrangement of each branch is
standardized and assumed by the
solution. (See Fig. 1.) Only the basic
eiectronic components shown in Figure 1
are recognized by the solution. Ohm's
Law covers voltage, c u r r e n t and
resistance but says nothing about
transistors, diodes or 7400s. Since only a
steady state solution is found in this
program, capacitors are considered open
circuits and inductors as short circuits.
However, with the
proper
combination of the a!!owed elements
shown in Figure 1, the user can "model"
transistors, diodes and other non-linear
components in a non-steady state and
non-D.C. anaiyzer.
Every branch must contain one and
only one non-zero r e s i s t a n c e or
conductance. According to Ohm's Law,
zero resistance requires an infinite
current flowing in the branch. Each
branch may have a voltage source,
current source or dependent current
source. Since this program has onty a
steady state D.C. analysis, the circuit
must have at least one independent
source, one node other than ground and
one branch. Every node must have a
path to ground through the branches of
the circuit. Without the path to ground,
certain sections of the circuit wouid
"fioat" free of the rest.
Starting with the number one, each
node is numbered in increments of one.
Ground is always node zero. Branches
and dependent current sources are
numbered consecutivety from one. There
is no branch or dependent source zero.
Output from the solution is in terms of
these numbers,
input Program
The input program is a compromise
between ease of programming and ease
of use. The easiest program to write
might ask for the number of branches
and then quiz the user on the values of it's
components and the nodes to which it is
connected. This would require a lot of
operator and computer time that could
be put to more productive use. The
easiest program wouid permit a user to
enter and edit any data in any order at
any time. But such a program would be
rather complicated to write.
C/N J u n e , 1 9 7 7
A L T A I R DC E L E C T R O N I C C I R C U I T A N A L Y S I S P R O G R A M
A D A P T E D F R O M IBM 1620 E C A P TO A L T A I R 8K B A S I C
( V E R S I O N 3 . 2 OR 4 . 0 ) B Y TOM S I M P S O N 2 / 1 4 / 7 7
!S C L E A R 9 9 : M O = 3 t D E F F N K X ) = I N T ( - ( X > 0 ) * X ) : I N P U T " N O D E S " ; X : M N = F M I < X - I )
20 I N P U T " B R A N C H E S " ; X : M B = F N I ( X - I ) ! INPUT"f)EP S C S " ; X : M D = F M I ( X - i )
33 DIH M(MB,HN),NI ( M B ) , H F ( M 3 ) , Z(M?) + !,MN + ! ) , Y ( M B ) , Y L < M B ) , Y H ( M B ) , C U ( M B )
43 DIM A(MB),AL(MB),AH(MB).,E(MB),EL<MB).,EH(MB),D(MD),DL(MD),Di:(MD)
5 0 DIM E C K M M ) , I P < M N ) , N V ( H H ) , B V < M B ) , I N ( M N , t ) , W ( M N ) , W L C M M ) , W H ( M N )
60 DIM R W ( M D > , C L ( M D : , S D ( M N ) ! D 3 = : " N B 3 " : K $ = " / X ( ) K M " : C $ = " B D * G R E I ":K!=t
70 P R I M T : P R I N T " A L T A I R DC E C A P " ; P R I N T : P S = " C M B V E V E C P L P D W C S D N V B C C ' 7 ! H " : K 0 = 3
KM=-I:K2=2
80 K 3 = 3 : K 4 = 4 : K 5 = 5 : K 6 = 6 : K 7 = 7 : K 9 = 9 : N N = K M : N B = K M : N D - K M : N Y = K M : N E = K M : M A = K M
90 P C = . 0 I :CT=* I 0 3 0 : C M = i E 6 : C I = . 0 3 H S 6 = 3 6
H 0 PH=K8
! 20 I N P U T X S : L = L E N (XS ) : 1=1(3: I F X S < > " R U H " T H E H 150
130 I F M Y - M B A N D ( N E * K M 0 R M A > K M ) A N D N B : * K M A N D N N : - K M T H E N 1 3 6 3
140 P R I M T " M I N R E Q U I R E M E N T S F O R S O L U T I O N H O T M E T " : E N D
150 I F X $ = " M O D I F Y " T H E N M O = M O + K H G O T O I 2 0
160 I F L E F T $ < X S , K I ) = " R " T H B N I 2 0
170 IFXS="NEW"THEN!0
189 I F L E r T S < X S , K 5 > = " P R I M T " T H E M I = K 5 : G O T O 9 0 0
190 IFXSs-"END"THENEND
200 I=I+Ki:IFI>LTHENI20
2 1 0 F0HK=KiT0K4!i I F M I D S ( X S , I,KI ) < > M I D $ ( C S , K , K t 3 T H E N M E X T : G O T O ! 0 0 0
220 OMKGOTO2S0,233,233,470
230 T Y = K - m { G 0 S U B 5 2 9 : X = T - K H I F T Y = K 2 T H E N 2 S S
240 IF'X>MBrHEKPRINT"BRANCH # T O O G R E A T " ; ! G O T O I 0 3 0
25B I F M 0 T H E N 4 7 3
260 IFND3-KHTHKa!PRINT"B R E C O R D S C A N N O T F O L L O W D R E C O R D S " ; : G 0 T 0 : 3 3 9
370 N B - K B + K I : G O T O 3 ! 0
289 I F X > M D T H E N ? n i H T " D E P S O U R C E * T O O G R E A T " ; : G O T O ! 0 3 0
230 I F M 0 T H E N 3 7 B
300 N D = M D + I
3iC
I=I+m:F0RK=KtT0K3:IFMID$(X$,I,KI)<*MID$(D$,K,Kt)THENMBXTsGOTO)M0
320 O M K G O T O 3 I ! S , 4 2 0 , 3 4 3
340 I F T Y = K ! T H K : H 0 8 O
353 GOSUB603:TL=TL-K! ! T H " T H - K 1 : ! F T L : ' M B O R T H * M B T H E N ! B I 0
330 C L ( N D ) = T L ! R W ( H 9 ) = T H
370 I = I + K I :F0RK=sK3T0H5:IFMIDS<XS*I'.Kl ) < > M I D $ ( D S , K , m ) T H E M H E X T : GOTO!. 330
380 IFK-K5THEK373
390 T T - K - K 2 : G 0 3 U B 6 ! S : I F T T - K 2 T H B N 4 I 0
400 K = C L ( N D ) : T - T * Y ( K ) : T L = T L * Y L ( K ) : T H = T H * Y H ( K )
410 D < M D ) = T s D L ( M 3 ) = T H D H ( N D ) = * T H : G O T O 123
420 IFTY=K2THS:mS33
433 GOSUB603:TL=TL-m :TH==TH'-KI : I F T L > M N O R T H * M N T H E M i 0 2 S
440 IFTL>MMTHEVtW"TL
4SS IFTH^MNTHE.'JMM="H
460 HKX)=fL:HF(X)=:TH
470 I-H-KIUFlP-LTHENtKf!
488 fORK^KSTOKy:IFMIMCXS.I,K:)<*MIDS(C$,K,Kt:THENMBXT:GOTO 1093
IFK=K9TKEH470
590
SB : IF!'"K^AND(TT=::!0RTT=K2)THEN iS43
513 T = K I / T : T I = T L : T L = K I / T H : T H = K I / H
520 Y ( X ) - T : Y L < X ) = T L : Y H ( X ) = T H : I F M O = K 0 T H E N N Y = N Y + K t
530 G O T O 4 7 0
540 E < X ) - T : E L C X ) = T L : E H ( X ) = T H : I F M O = K 0 T H E N N E = N E + K t
550 GOTO470
560 A ( X ) = T : A L ( X ) = T L : A H ( X ) = T H : I F M O = K 0 T H E N N A = N A + K !
570 G O T O 4 7 0
600 ZZ=K2tGOTO650
610 ZZ=KI:GOTO630
620 Z Z = K 0
630 I = I + K t : Z S " M I D $ ( X S , I , K t ) : I F Z $ = " " O R Z S = " = " T H E N 6 3 0
640 GOSUB790:T=Ti*MU:IFZZ=K0THENRETURN
650 I = I-<-K!:IFMIDKX$,I,KI) = " "THEN650
6 6 0 IFt-!ID$(X$^I,Kt ) < > " ( " T H E M T L = T : T H = T : I = I - K H O N Z Z G O T O 7 6 0 , 1030
670 I-H-KIiGOSUB790:TL=TI^MU
680
I=I+m:F0RK=KIT0K3:IFMID$(X$,I^KIX>MID$(K$^K^K!)THENNEXT:GOTOI003
690 ONKGOTO6S0,700,7:0
7 0 0 I=I-)'K) ! G O S U B 7 9 6 : T H = T I * M U : G O T O 7 3 0
7!0 IFZZ<*KtTHEN!060
7 20 T L " A B S ( T ) * T L * P C : T H = T + T L : T L = T - T L
730 I = H K 1 : I F I > L O R M I D $ C X $ , I , K ! ) = " ) " T H E N R E T U R N
740 IFMID$(X$,I^KI)=" "THEM730
750 GOTO!000
760 RETURN
790
CONTiNUED
Ti=VAL(MIDS<X$,I))
SEVENTEEN
Circuit Analysis
Applications
660 F0RJ=IT0I.:F0RK=K!T0K7: I F M I D S ( X S , J , K I )<>MID$(K$,K,K1)THENNEXTK,J
830 I = J - K 1 : M U = K 1 : I F Z Z < > m 0 R K < K 6 0 R K * K 7 T H E N R E T U R M
840 I = I+K! : I F T T = K 2 A U D K = K 6 T H E N H U = C T : R E T U R N
C O N T I N U E D 850 I F T T = K 2 A N D K = K 7 T H E H M U = C M : R E T U H N
860
I=I+K1:IFTT=K3AMDMID$(XS,I,m)="V"THEN8!8
The f o r m a t used here f a l l s
870 I F T T = K 4 A M D M I D S < X 3 , I , K I ) < > " A " T H E N 1000
s o m e w h e r e in between these t w o 890 MU=CI:RETURN
extremes, it's not a particularly simple 9 0 0 I = I + K 1 : I F I > L T H E N 1 2 0
910 I F MID$<X<6,I,K1) = " "THEN900
p r o g r a m , but it's straightforward.
920 H*MIDS(XS,I,K3)="ALL"THENPR=4095:GOTO!20
Although it doesn't allow a compietely 930 F 0 R K = K 8 T 0 1 1 : I F H I D S C X S , I , K 2 ) o M I D $ ( P S , K 2 * K + K ! , K 2 ) T H E N N E X T : G O T O 1 0 0 0
940 PR=PR0RCK2'K>:I=I+K!:GOTO930
free format, it's fairly easy to learn,
1000 P R I N T " S Y H T A X E H R 0 R - P 0 S . " ; i : E N D
input Format
1010 P H I N T " B R A N C H # T O O G R E A T " : E N D
See the sample runs for the input 1 0 2 0 P R I N T " M O D E F T O O G R E A T " : E N D
1030 P R I N T " - T R Y A G A I N " : G O T O 1 2 0
format. Branches are described with the 1 0 4 0 P R I N T " Z E R O R E S I S T A N C E O R C O N D U C T A N C E N O T A L L O W E D " : E N D
letter " B " as the first non-space i 8 6 0 I F P R = K 3 ? H E N P R I N T " N 0 O U T P U T S P E C I F I E D " J < G O T O 1 0 3 0
MODIFY";MO;"**":GOTO1090
character and followed by the branch 1 0 7 0 P R I N T : P R I N T : P R I N T : P R I M T : I F M O T H E N P R I N T " * *
1080 PRINT"** S O L U T I O N * * "
number. A node " N " is foliowed by two 1 0 9 0 P R I N T : P K I N T : P R I N T
node numbers in parenthesis. The first 1 I 0 C F O R K = K 0 T O N B : F O R J = K 0 T O N N : M ( K , J ) = K 0 : N E X T J , K
number is the initiat node of this branch. 1 1 1 0 F O R I = K O T O N B : I F H l ( I ) * : 9 M T H E N M ( I . , M I ( I ) ) = K I
!I20 I F M F ( I ) > K M T H E K H ( I , N F ( I ) ) = K M
The second is the final node. Initiat and 1 1 3 3 N E X T
final nodes a r e determined by the 1 2 0 0 F 0 R I = K S T 0 N N : Z ( I , N N + K 1 ) = K 0 : Z ( N M + K I , I ) = K 0 : F O K J = K 9 T O N N : Z ( I , J ) = K 0
positive current direction in the branch, 1 2 1 0 F O n K = K 0 T O N B : T - M ( K , I ) : T 1 = M ( K , J ) : I F T = K 0 O R T ! = K 0 T H E N 1 2 3 S
1220 2 ( I , J ) = Z(I,..!H-TaTI*Y(K)
which is set arbitrarily by the user. 1 2 3 0 H E X T K , J , I : I F M D = K M T H E N ! 4 0 S
Current flows from the initial node to the I 3 S 0 F O R I = K 0 T O N D : L = R W < I ) : H = C L t I ) : F O R J = K 0 T O N N : F O R K = K 0 T O M N
final node. Then the component values in 1 3 1 0 T = M < L , J ) : T 1 = M ( M , K ) : I F T = K 0 O R T 1 = K 0 T H E N 1 3 3 0
1320 Z < J , K ) = ^ Z ( J , K ) + T * T l a D ( I )
the branch are entered in any order. R = 1 3 3 9 H K X T K , J , I
d e f i n e s r e s i s t a n c e , G = d e f i n e s !4SP FORi-K<atON3!CU;i ) = K S :CU( I ) = A ( I ) - Y (
I ) :NEXT:IFND=KMTHEH1440
conductance, E = defines voltage source 1 4 I B F 0 R I - K 8 T 0 M D : L = R W ( I ) : L i - C L < I )
I42& I F E { L l ) T H E H C m L ) = C U ( L ) - G ( I ) * E C L l )
and 1= defines independent current
14 30 NEXT
source. Only component values included 1 4 4 8 FORN-KCTCNN:::^.(N) = K 0 : F O R M = K 0 T O N B : E O C N ) = E Q ( N ) ^ < t I ^ . M ) ^ C U ( t n : H E X T M , N
in the branch should be specified. The l.^ss iFPRju-iDi:lT:-::riG0SU325B?
only thing missing from F i g . 1 is 1500 FORI=K0TONM:IP(I)=K0:NEXT:FORI=K0TONN:T=K0:FORJ=K0TONN
*i510 I F I P ( J ) = K ! T H E N 1 5 6 0
d e p e n d e n t c u r r e n t sources, w h i c h 1520 FORK=0TONN)IFIP(K)>KITHENRETURN
sometimes cause modeling difficulties. 1530 IFIP<K)=K1THENI550
1540 I F A B S ( Z ( J , K ) ) ^ A B S C T ) T H E N I R = J ) I C = K : T = - Z ( J , K )
A dependent current source has a 1550 NEXTK
value which depends on a quantity in 1560 NEXTJ
1570 I P ( I C ) = I P ( I C ) + K 1 : I F I R = I C T H E N 1 5 9 0
another branch of the circuit iine.
1580 FORL=K0TONN:T=ZMR,L) : Z < I R , L ) = Z ( I C , L ) : Z ( I C ^ L ) = T : N E X T L
Dependent current sources are carried 1590 I N ( I , K 0 ) = I R : I N ( I , K ! ) = I C : P V = Z ( I C , I C ) : Z ( I C , I C ) = K 1
internally as transconductance vaiues. 1600 FORL=K0TONN:ZMC,L) = Z<IC.,L)/PV:MEXTL
1610 FORLI=K0TONN:IFH=iICTHENi640
Another often used value is current gain 1620 T = Z < L ! , I C ) : Z t L l , I C ) = K 0 : F O R L = K 0 T O N N
or beta value. The values are related by 1630 Z ( H , L ) = Z ( L 1 , L ) - Z ( I C , L ) * T : N E X T L
the equation: Transconductance = beta 1640 NEXTL!
1650 N E X T I
/ resistance of controiling branch. The 1660 F O R I = N N T O K 0 S T E P K M : 1 F I N { I ^ K 0 ) = I N ( I , K 1 ) T H E N 1690
IR=IM{I,K0):IC=IN(I,K1):FORK=K0TONN:T=Z(K,IR):Z(K,IR)=Z(K,IC)
problem is that if a beta vaiue is used to 1670
describe a dependent source, then the 1680 Z ( K , I C ) = T : N E X T K
1690 NEXTI:IFPRANO2048THENGOSUB2600
resistance of the controiling branch must 1700 FORN=<K0TONN:NV(N)=K0:FORM=K0TONN:NV(N)=NV(N)'<-Z(N,M)^EQ(M) :NEXTM,N
be previously defined. Otherwise, a 1710 IFPRAND256THENGOSUB2450
17S0 FORM=K0TONB:BV(M)=K0:FORM=K0TONN:BV(M)=BV<M)+M(M,N)*NV(M):NEXTN^M
"divide by zero" error occurs when the 1730 IFPRANDK2THENGOSUB2700
expression above is e v a i u a t e d . So, 1740 FORI=K0TONB:BV(I)=BV(I)+ECI):NEXT:IFPRANDK4THEHGOSUB2800
d e p e n d e n t s o u r c e s a r e e n t e r e d 1750 F O R I = K 0 T O N B : C U ( I ) = K 0 : C U ( I ) = Y ( I ) * B V ( I ) - A < I ) : N E X T : I F N D ^ K M T H E N ! 7 9 0
1760 F O R I = K 0 T O N D : L = R W ( I ) : L 1 = C L ( I )
separateiy and only after alt other -1770 I F B V ( L 1 ) T H E N C U ( L ) = C U ( L ) + D < I ) * B V ( L ! )
branch data has been entered. Line 260 in 1780 NEXT
the program does not tet the user enter 1790 IFPRANDS12THENGOSUB2900
1800 FORI=K0TONB:CU(I) = C U ( I ) + A ( I):NEXT:IFPRAND8THENGOSUB3000
any more branch data after one or more 1810 FORI=K0TONB:CU(I)^CU(I)*BV<I):MEXT:IFPRAMD16THENGOSUB31O0
1820 FORI=K0TONB:BV<I)=BV(I)-E<I):NEXT:IF(PRAND224)=K0THEN110
dependent sources are entered.
1830 F O R J = K 0 T O M N : T = N V ( J ) : W ( J ) = T : M L ( J ) = T : M H { J ) = T : S D { J ) = K 0 : N E X T
The input line for dependent sources 1840 PV=K1 :F0RIT=K1T0K4:NU=NB! IFITOK2THEM1870
fotiows the format branch data. The first 1850 IFND=KMTHEN2360
non-space c h a r a c t e r is t h e letter I 8 6 0 NU=ND
1870 FORI=K0TONU:ONITGOTO1910,1910,1880,1900
" D " , followed by the dependent source 1880 IFE(I)=K0THEN2350
number. Next is a branch group with the 1890 GOTO1910
letter " B " , followed by two branch 1900 IFA(I)=K0THEN2350
1910 FORJ=K0TONN:NV(J)=K0:NEXTJ:ONITGOTO1928,!930,1940,1990
FOURTEEN
C/N June. 1 9 7 7
1920
1930
1940
1950
I960
!970
i960
1990
2000
2010
2020
2030
2040
2050
2060
2070
2080
2090
2100
2110
2115
2120
T 1 = Y ( I ) * Y ( I ) * ( E < I ) + B V ( I ) ) : I I = I : T R = K 1 !GOTO2000
H = R M ( I ) : J J = C L ( I ) :T!=*- ( E ( J J ) + B V ( J J ) ) : T R = K 3 : G O T O 2 0 0 0
IFND=KMTHEN1980
F O R J = K 0 T O N D : I F I < > C L < J)THETM970
II=RM(J):T1=-D<J):TR=K4:GOTO2000
NEXTJ
II=HT1=<-Y(I):TR=K3:GOTO2300
II=I:T1=K1:TR=K3
IFMI(II)=KMTHENNI=NN+K1:GOTO2020
NI=NI(II)
IFNF(II)=KMTHEMNF=NN+K1:GOTO2040
NF=NF(II)
FORM=K0TONN:NV{N)=NV(N)+(Z(N,NI)-Z<N,NF))*T1:MEXTN
ONTRGOTO2060,2090,2100,1970
IFND=Kt^THEM2100
FORJ=K0TOND: I F K > C L ( J ) T H E N 2 0 9 0
II=RW(J) :T1=Y(I)=)=DCJ)*(E(H+BV(I)){TR=K2:GOTO230B
NEXTJ
IF(PRAND32)=K0THEN2240
IFPVTHSNPRINT:PRINT"*PARTIAL DERIVATIVES*":PV=K0
P R I M T : P H I N T " N O D E VOLTAGES WITH RESPECT TO " J
0HITG0T02130,2149,2150,2160
2150
2160
2178
2180
2190
2200
2210
2220
2230
2240
2250
2260
2270
2280
2290
2300
2310
2320
2330
2340
2350
2360
2370
2380
CNN
2390
2400
2410
2420
2430
2450
= KM
2460
2470
PRINT"VOLTAGE SOURCE IN B R A N C H " ; i + K H G 0 T 0 2 1 7 3
PRIMT"CURRENT SOURCE ACROSS B R A N C H " ; I + K l
PRINT!ONITG0T02130,2190,2200,2210
T1=PC/Y(I):GOTO2220
T1=PC*D<I):GOTO2220
T1=PC*E{I):GOTO2220
T1=PC*ACI)
PRINT"NODE M O . " , " P A R T I A L S " , " S E N S I T I V I T I E S " : P R I M T { F O R N = K 0 T O N N
T=NV(N)*ABS(T1):PRINTN+K1,MV(N),T:NEXTN
ONITGOTO2250,2260,2270,2280
T1=(Y<I)-YL(I))/(Y(I)*YL(I)):T2=(Y(I)-YH(I))/(Y(I)*YH(I)):G0T02299
T1=DH(I)-D(I):T2=DL(I)-D(I):GOTO2290
T1=EH(I)-E{I):T2=EL(I)-E(I):GOTO2290
T1=AH(I)-A<I):T2=AL<I)-A<I)
T=T1-T2:FORJ=K0TONN:ONSGN<NV(J))+K1GOTO232*0,2310
WH(J)=WH(J)+NV(J)*T2:WL<J)=WL(J)+NV<J)*T!:GOTO2320
HH(J)=WHCJ)+NV(J)*T1:ML(J>=VL<J)+NV(J)*T2
NEXTJ:T=T*T/S6:FORJ=K0TONN:IFMV(J)=K0THEN2340
T1=NV{J):SD{J)=SD(J)+T1*T1*T
MEXTJ
NEXT!
NEXTIT:IF(PRAND64)=K0THEN2400
PRINT : P R I N T " * W O R S T CASE NODE V O L T A G E S * " : P R I N T
PRINT"NODE N O . " , " N O M I N A L C A S E " , " V . C . M A X " , " W . C . M I N " : P R I N T : F O R J = K 0 T
n u m b e r s in parenthesis. The first branch
n u m b e r is the controlling branch. The
second
is t h e
branch
in
which
the
dependent source resides. The next v a i u e
is the t r a n s c o n d u c t a n c e or beta v a l u e :
G=
defines t r a n s c o n d u c t a n c e and B =
defines c u r r e n t g a i n .
A s s u m e d units a r e o h m , mho, volt
and a m p e r e . The following
multipliers
are avaiiable: K = kilohm, M = megohm,
MV=
m i l l i v o l t and M A =
Numeric
values
can
miHiampere.
be in
any
form
a c c e p t a b t e to BASIC'S V A L function.
in m a n y cases it's desirable to obtain
a
" w o r s t c a s e " a n a l y s i s of a
circuit.
Circuit values a r e never absolute and
v a r y in ranges, i.e. + 5%, + 10% etc. So
0
PRINTJ+K1,W(J),WH<J),WL(J):NEXT:PRINT:PRIMT
IF<PRAND128)=K0THEMPRINT:PRINT:GOTO110
P R I N T : P R I N T " * S T A M D A R D DEVIATION OF NODE V O L T A G E S * " : P R I N T
PRINT"MODE N O . " , " S T D .
DEV.":PRINT:FORI=K0TONN
PRINTI+K1,SQR(SD(I)):NEXT:PRIMT:PRINT:GOTO!10
PRINT:PRINT"*NODE
VOLTAGES*":PRINT:PRINT"NODES","VOLTAGES":PRINT:LA
the actual value installed in a circuit is
u n k n o w n unless explicitly m e a s u r e d . A
worst case a n a l y s i s allows c o m p o n e n t s
with specified toierance to v a r y during
evaiuation.
To obtain a worst case analysis or
standard
deviation
tolerance
values
of
node
for
one
voltages,
or
more
p a r a m e t e r s should be entered. They are
entered as m i n i m u m / m a x i m u m
or
a
percentage
nominai
value,
which
and
values
follows
the
enclosed
in
parenthesis. Both types a r e shown in the
s a m p l e runs.
By specifying a tolerance on one or
more
key
component
values
in
the
circuit, t h e effect on the possible range
can be d e t e r m i n e d on the desired output.
Numeric
values
must
have
some
a c c e p t a b l e t e r m i n a t i n g c h a r a c t e r . Since
the input is into a string and
numeric
values a r e extracted using V A L , some
m e a n s of f i n d i n g t h e end of the n u m b e r is
needed to continue the scan of the input
K=LA+K1:LA=LA+K4:IFLA>NNTHEMLA=NN
P R I N T K + m " - " L A + K ! , : F O R J = K T O L A : P R I M T N V < J ) , : N E X T : P R I M T : I F N M > L A T H E M 2 4 6 line. The first method I used w a s to
2480 PRINT:PRINT:RETURN
2 5 0 0 P R I N T : P R I N T " * N O D A L CONDUCTANCE M A T R I X * "
2510 PRINT:PRINT"ROM
COLS.":PRINT:FORI=K0TONN:LA=KM
2 5 2 0 K=LA+K1::LA=LA+K4:IFLA>NNTHENLA=NN
2530 P R I N T : P R I N T I + K 1 "
"K+K1"-"LA+K1,:FORJ=KTOLA:PRINTZCI,J),:MEXTJ:IFMN>
LATHEM2520
2540 PRIMT:NSXTI:PRINT:PRINT:PRINT:RETURN
2 5 5 0 P R I N T : P R I N T " * E Q U I V . CURRENT V E C T O R * " : P R I N T : P R I M T " M O O E M O . " , " C U R R E N T
2 5 6 3 PRINT!FORI=*K0TOMN : P R I N T I + K 1 , E Q < I ) : N E X T I : : P R I N T :RETURN
2 6 0 0 P R I N T : P R I N T " * N O D A L IMPEDANCE M A T R I X * " : 6 0 T 0 2 5 1 3
2 7 0 0 P R I N T : P R I N T " * B R A M C H VOLTAGES*"
2710 PRINT:PR?MT"BRAMCHES","VOLTAGES":LA=KM
2 7 2 0 K=LA+K1:LA=LA+K4:IFLA>NBTHENLA=NB
2730
P3INT:PRINTK+K1"-"LA+K1,:FORJ=KTOLA:PRINTBV(J),:M6XTJ:IFNB>LATHEN27
20
c o m p u t e the
number
of c h a r a c t e r s
a
n u m b e r used on the input line using L E N
( S T R $ ( X ) + ( X ) = % ) . However, a n u m b e r
entered as 4.25E3 causes the expression
a b o v e to e v a l u a t e to L E N ("4250") + (-D
=
4, o r
two
less
characters
than
" 4 . 2 5 E 3 " . This m e t h o d did not work for
exponential n u m b e r s . So ) decided upon
another
solution, which
allows use of
exponential n u m b e r s and m o r e flexible
input. This final solution uses n u m e r i c
vaiues
immediateiy
followed
by
some
t e r m i n a t i n g c h a r a c t e r . The c h a r a c t e r s
a r e space,/, ( , ) , % , K , M and end-of-input
CONTtNUED
tine. They are in K$ and are frequently
used in t h e input string.
C/N June,
1977
SEVENTEEN
Sotution a n d Output
2740
PRINT:PRINT:RETURN
T w e t v e v a t u e s a r e a v a i l a b l e f r o m t h e 3 8 0 0 PRINT:PRINT--*ELEMENT VOLTAGES*":GOTO2710
PRINT:PRINT"#BRANCH CURRENTS*":GOTO38!0
sotution. A n y c o m b i n a t i o n Of o u t p u t 3000 PRINT:PRIMT"*ELEMENT CURRENTS*"
values can be specified by an input line 3010 P R I N T : P R I N T " 3 3 A N C H E S " , " C U R R E N T S "
+
DEHMT
l o f t 3020 P R I N T : L A = m
containing the word P R I N T , ' e f t ^
K=LA+K1:LA=LA+K4:IFLA>NBTHENLA=NB
{ u s t i f i e d , f o l l o w e d b y t w o - l e t t e r 3040
PRINTK+K1"-"LA+K1,:F0RU=KT0LA:PRINTCU(J),:NEXT.J:PRINT:IFN3>LATHEN33
abbreviations for each desired value. 30
f S . o Tahlc 1 1 The wnrH At ) fnllnwinn ^ ^ ^
PRINT:PRINT!RETURN
^ e e l a o i e 1.; t n e w o r a /it-t-Tonowmg
P R I N T causes ail output to be printed.
One variable, P R , is used to store the
output information. E a c h bit of P R is set
to a value of one for one specific output
^ ^ ^ PRIMT:PRINT"*ELEMENT POWER L O S S E S * " : P R I N T : P R I N T " B R A M C H E S " , " P O W E R
SSES":GOTO3820
""
* * * * * S A M P L E R ^ OF ALTAIK DC ECAP
3/12/77
*,m*+sTARTING WITH THE C I R C U I T IN F I G . 2
LO
type using the O R operator. The bits of RUN
P R a r e tested using the A N D operator MODES? 2
A A A
.
BRANCHES? 3
w h e n d i f f e r e n t o u t p u t v a l u e s a r e p g p scs? 0
avaitabie. Any n u m b e r of P R I N T lines
can be used anywhere in the input.
ALTAIR DC ECAP
The word R U N , left justified, starts ? R
THE NODES AND BRANCHES HAVE ALREADY BEEN NUMBERED
thesoiution. F i r s t a c h e c k i s m a d e t o s e e ? R
. .
^
, A? R
tf the m t n t m u m c o n d t t i o n s for a s o l u t i o n ^
BRANCH l HAS I N I T I A L NODE 0
AT^ FINAL NODE 1
N ( 8 / l ) R=3 E=24
have been met. Line 130 checks for a ? R
BRANCH 2 HAS I N I T I A L NODE 2
resistance
branch.
or
There
conductance
must
(GROUND)
in
every ? ^
FINAL NODE !
? B2 N C 2 / 1 ) R=4
least one ? R
BRANCH 3 HAS I N I T I A L NODE 2
be at
AND FINAL NODE 0
independent source, at least one branch ? R
and at ieast one node. Line 1060 checks ?
?
for specified output.
?
A f t e r s o i u t i o n a n d p r i n t o u t is ?
. . .
A
1 n. ?
compiete, the p r o g r a m returns to the ^
^
^
^
^
R
FOR OUTPUT GET MODE VOLTAGES
R
AND BRANCH CURRENTS
PRINT NV BC
R
READY FOR SOLUTION
p ^
input routine. Several things a r e now
possibie.
"END"
command
returns
level. " N E W "
to
BASiC * *
SOLUTION
restarts t h e * N ° ° E
**
VOLTAGES*
p r o g r a m f r o m the beginning and resets MODES
VOLTAGES
aii circuit va);ues. Since the solution does
not a l t e r
any
input
data,
additional
* * 2
*S
10
output can be specified and another R U N *BRANCH CURRENTS*
m a d e . The print variable, P R , is reset to BRANCHES
zero or no output after each
Each
RUN
CURRENTS
solution.
produces only the output
1 * 3
2
-2
2
requested for that R U N .
Modify
? R
The word M O D I F Y ,
left j u s t i f i e d , ?
?
increments the modtfy flag, variable ?
MO. Data that changes component ?
THE CURRENT IM BRANCH 2 I S NEGATIVE OR
"
R
R
R
OPPOSITE IN DIRECTION TO THAT WHICH
WAS ASSIGMBD
NOV MODIFY THE C I R C U I T TO BS F I G .
3
values can then be entered. Changing a ? R T H E V O L T A G E S O U R C E iN B R A N C H 1 iS N O W 12 VOLTS
vaiue to zero effectivety removes t h e ?
R
THE RESISTANCE
IN BRANCH 3 I S NOW n
OHMS
component f r o m the circuit. New sources ? B3 R = n
,_
^
.
A
R
SET THE SAME OUTPUT
c a n be e n t e r e d in a n y e s t a b t i s h e d ? PRtMT NV BC
b r a n c h . N e w b r a n c h e s c a n n o t b e ? RUN
entered.
* * MODIFY
To modify a branch, enter the letter ^ Q ^ g
l
**
VOLTAGES*
" B " and the branch n u m b e r . O m i t the
node g r o u p and enter the new values i n , " ° ° E S
this branch. Component values that wilt
not
be c h a n g e d
can
be o m i t t e d .
To ^
:
- 2
^
VOLTAGES
10
7.33333
CURRENTS*
modify a dependent source n u m b e r , o m i t
the
branch
group
and
enter
n e w BRANCHES
transconductance or beta vaiues. if beta
CURRENTS
.666667
-.666667
.666667
values a r e entered, the resistance in the
controiiing
EIGHTEEN
branch
shouid be changed
C/NJun6.
1977
?
?
?
?
?
?
?
?
T
?
?
7
H MODIFY IT AGAIN TO BE F I G .
MODIFY
B I R=5 E=-24
R
THE VOLTAGE SOURCE IN F I G .
R
I S OPPOSITE IN POLARITY TO
R
STANDARD BRANCH ( F I G .
I)
B3 E=12 R=6
R
INCLUDE BRANCH VOLTAGES IN
PRINT BC
R FORGOT SOME
PRINT NV BV
RUN
MODIFY 2
first
4
4 BRANCH
THE
the
"B"
command,
if
the
Once the word M O D ) F Y is entered,
I
only
circuit
performed.
modifications
However,
they
can
be
can
be
performed as m a n y times as necessary.
THE OUTPUT
If the ability to a d d
branches to the
circuit is necessary, the p r o g r a m must
be changed to allow the modify flag, M O ,
to be reset to zero.
**
Subroutines a r e used for printing alt
*NODE VOLTAGES*
MODES
with
resistance is changed at ait.
output except partiai derivatives, worst
VOLTAGES
I - 2
-20
*BHAMCH VOLTAGES*
case and standard deviation, which a r e
computed only if output is requested.
-16.8
Genera) P r o g r a m Description
Lines 10 to 110 set up the p r o g r a m .
BRANCHES
'
VOLTAGES
- 3
Function FNI m i n i m i z e s its a r g u m e n t to
20
BRANCHES
3.2
-16.8
zero, avoiding a FC error in the D ) M
statements. Three input statements get
CURRENTS
maximum
nodes,
dependent
? R WANTED RESISTOR
? PRINT EC
? RUN
* * MODIFY 2
*ELEMENT
CURRENTS TOO
different
sources
memory
execution,
branches
to
sizes.
variabies
and
accommodate
To
are
speed
used
for
constants.
**
Lines 120 to 570 process the input
CURRENTS*
line. " R " as the first character on the
BRANCHES
I
CURRENTS
- 3
line causes the line to be ignored and can
-.8
.6
-.8
? R NOW ANALYZE THE SINGLE STSGE COMMON EMITTER
? R
A M P L I F I E R IN F I G . 5
? R
THE E9UIVALENT C I R C U I T I S SHOWN IN F I G . 6
? R
CAPICATORS HAVE BEEN REPLACED
? R WITH OPEN C I R C U I T S AMD THE 2N657
? R TRANSISTOR WITH I T ' S EQUIVALENT.
? R
THERE ARE THREE NODES-SIX BRANCHES7 R
AND ONE DEPENDENT SOURCE.
7 R HAVE TO START OVER-7 NEW
NODES? 4
BRANCHES? 9
DEP SCS? 3
SOLUTION
**
470. The next non-space character of a
continuation line must be R, G, E or h
Dependent source input tines cannot be
continued.
The processing of an input tine is
simple. Look for " B " or " D " , find its
numbers
range
group, check the
and
then
extract
p a r a m e t e r vatues, putting them in the
appropriate
carried
matrix.
internalty
Resistance
is
as conductance.
At
line 510 m i n i m u m - m a x i m u m
resistance
tolerances become m a x i m u m - m i n i m u m
conductance tolerances.
The subroutine at line 600 contrcfts
extraction
of n u m e r i c
vatues.
tt
has
three entry points at lines 600, 610 and 620
n u m b e r s ) , two n u m b e r s in parenthesis
(node or branch group) or both ( n o m i n a i
fint
1
1 - 3
4.0238IE-03
0
-2.857!4E-03
2
1 - 3
.142857
5.9009E-04
-.142947
3
1 - 3
-.145714
-9.0090IE-05
.147804
CONTINUED
C/NiJune. 1977
the p a r a m e t e r extraction routine at line
to extract a single value ( " B " or " D "
*NODAL CONDUCTANCE MATRIX*
HUM
of the previous line and causes a j u m p to
the node or branch
R
T H I S TIME INCLUDE TOLERANCE VALUES FOR
R WORST CASE ANALYSIS AND STANDARD DEVIATION
R
B I N ( 0 / 2 ) R = 2 K ( 7 X ) E=*20(5S)
B2 N ( 0 / I ) R = 6 K ( 7 ^ )
* E=20<19/21)
B3 N ( 0 / I ) R = I 0 0 0 ( 7 S )
B4 N ( I / 3 ) R = 3 5 0 ( 1 8 3 ) E=-500MV
B5 N ( 3 / 0 ) R = 5 0 0 ( 4 6 5 / 5 3 5 )
B6 N < 2 / 3 ) R = ! l . ! E 3 ( t 0 % )
D! B ( 4 / 6 ) B=50(I0X)
PRINT ALL
RUN
**
Using an asterisk as the first character
indicates that this iine is a continuation
n u m b e r , check the n u m b e r ' s range, find
ALTAIR DC ECAP
?
?
?
?
?
?
?
?
?
?
?
?
?
be used to insert r e m a r k s into the input.
and tolerance values).
Subroutine 790 to 890 extracts vatues,
finds their length on the input line and
retrieves the multiptier, if present. The
value is returned in T1 and the^muitipiier
value in M U .
n
NtNETEEN
Lines 900 to 940 handle the P R I N T
input
line. Each two-letter group is
"NODAL IMPEDANCE MATRIX*
ROW
COLS.
compared to aitowed commands in P$ by
loop variable K. When a c o m m a n d is
1 - 3
found, K has the bit number that needs to
!
be set to one. Two raised to the power K
has the decimal equivalent needed in
BASiC. Using the OR operator to set the
bits doesn't change any bits already set.
Setting the same bit more than once has
no effect either.
Lines
1000
to
1040 a r e
error
messages. Error detection is limited and
is not recoverable except when an error
occurs at the beginning of the input iine
in a " B " or " D " number.
Lines 1100 to 1130 set up matrix M —
the nodal connectivity matrix, it is set to
_+ 1 or zero, indicating which branches
are'connected with which nodes. The
values indicate: 1 = initiat node, -1 =
3
- 3
1 - 3
823.889
2.85272
18.6852
-3163.61
1977.27
1851.14
810.31
4.01752
26.3149
U.0728
2.26853
-2.79423
.525696
-2.79423
.0256958
+NODE VOLTAGES*
MODES
VOLTAGES
1 - 3
2.79423
*BRANCH VOLTAGES*
BRANCHES
VOLTAGES
1 - 4
-11.0728
-2.79423
5 - 6
2.26853
* ELEMENT VOLTAGES*
8.80427
BRANCHES
VOLTAGES
1 - 4
8.9272
branch. If one node of a branch is ground,
5 - 6
2.26853
*BRANCH CURRENTS*
no information is entered into matrix M .
BRANCHES
finai node and 0 = node not connected to
17.2058
8.80427
CURRENTS
Instead, it is implied by the absence of
1 - 4
4.4636E-03
^ELEMENT CURRENTS*
one node.
2.86763E-03
-2.79423E-03
2.79423E-03
2.86763E-03
-2.79423E-03
7.34167E-05
Lines 1200 to 1290 set up matrix Z —
the nodal conductance matrix. Z is a
square matrix
with dimensions
max.
BRANCHES
1 - 4
CURRENTS
4.4636E-03
nodes +1 by max. nodes +1. Its vaiues
are the conductance between the nodes
indicated by the subscripts. When the
subscripts are the same, vaiues on the
major
diagonal
give the
conductance
from the node to ground.
5 - 6
4.53706E-03
^ELEMENT POWER LOSSES*
BRANCHES
1 - 4
4.46401E-03
POWER LOSSES
.0398475
.0493398
.0102925
DERIVATIVES*
.0393023
transconductance values to matrix Z if
5 - 6
*PARTIAL
there are any dependent current sources
NODE VOLTAGES WITH RESPECT TO RES.
Lines
1300
to
1380
add
7.80771E-03
1.8865E-06
IN BRANCH 1
In the circuit.
Lines
1400 to 1430 c o m p u t e
the
current for each branch in matrix CU.
Lines
1440 to 1450 p r o d u c e
EQ=M*CU
— an equivalent
matrix
current
vector for each node.
1690, changing Z to a nodal impedance
matrix. There are node resistances in
matrix Z and equivalent node currents in
matrix EQ. The product N V = Z * E Q is
taken at iine 1700, setting the NV matrix
to node voltages. (Ohm's Law)
1720 t a k e s t h e
difference
between initial and finai node voitages
and gives branch voitages in matrix BV.
Resistor
(element)
voltages
are
computed at iine 1740. The source voitage
is added to the branch voltage. Resistor
voitage is a voltage drop, and source
voltage is a voitage rise or negative
FOURTEEN
1
2
3
PARTIALS
SENSITIVITIES
-6.36671E-06
-4.41288E-03
-8.9663E-06
-1.27334E-04
-.0882576
NODE VOLTAGES WITH RESPECT
Matrix Z is inverted at lines 1500 to
Line
MODE NO.
MODE NO.
1
2
3
PARTIALS
-3.93768E-04
1.51201E-03
-3.87278E-04
-1.79326E-04
TO RES.
SENSITIVITIES
-.0236261
.0907207
-.0232367
NODE VOLTAGES WITH RESPECT TO RES.
NODE NO.
IN BRANCH 2
IN BRANCH 3
PARTIALS
SENSITIVITIES
2.30213E-03
-8.S39SSE-03
2.26419E-03
.0230213
-.0883985
.0226419
MODE VOLTAGES WITH RESPECT TO RES. IN BRANCH 4
NODE NO.
PARTIALS
SENSITIVITIES
2.84905E-96
2.70973E-04
-6.94049E-05
9.97166E-06
9.48406E-04
-2.42917E-04
C/N June. 1977
MODE VOLTAGES WITH RESPECT TO RES.
MODE NO.
1
2
3
*E*UIV.
PARTIALS
1.69551E-04
.0167975
2.38785E-04
CURRENT VECTOR*
voltage drop. This is refiected in Fig. 1 by
IN BRANCH S
the source and resistor voltages that are
SENSITIVITIES
opposite in polarity. The branch voltage
S.47757E-04
.0339875
1.19392E-03
is the sum of the voltage drop in the
branch or BV = EV + (-E) and EV = BV
+ E.
Lines 1750 to 1780 compute branch
MODE NO.
1
2
3
CURRENT
currents in matrix CU by using O h m ' s
4.7619E-03
.0814286
-.0728571
adding the dependent current source and
Law (!-E*G) to find the resistor c u r r e n t
subtracting
NODE VOLTAGES WITH RESPECT TO RES.
MODE MO.
IN BRANCH 6
the
independent
current
source. The independent current source
is subtracted rather than added, because
PARTIALS
SENSITIVITIES
1
2
-1.13134E-06
9.0I302E-06
-I.25579E-04
I.30045E-03
current.
3
-1.59331E-06
-1.76858E-04
source back
it is opposite in direction from the branch
By adding the independent current
NODE VOLTAGES WITH RESPECT TO GM. BRANCH 4 TO BRANCH 6
NODE MO.
PARTIALS
SENSITIVITIES
21
. 4. 2
06
-3
48
12
07
5
I 8027E
- 45..683I 0
E-0
04
3
3
.57295
in at
line 1800, resistor
currents are computed in matrix CU.
Line 1810 computes the power iost in
each resistor as the product of resistor
current and voltage.
Line
8.185E-04
1820 returns
matrix
BV
to
branch voltages.
Lines 1830 to 2240 compute partia!
MODE VOLTAGES WITH RESPECT TO VOLTAGE SOURCE IN BRANCH I
derivatives of node voltages with respect
NODE NO.
PARTIALS
SENSITIVITIES
to each circuit parameter. They also
21
26
63
36
.19.84 8
7E-03
85
.21. 9
72
77
22
7E - 0 4
compute
3
2.00876E-03
4.01752E-04
for
NODE VOLTAGES WITH RESPECT TO VOLTAGE SOURCE IN BRANCH 2
PARTIALS
SENSITIVITIES
21
37
72
36
19
5
- .. 51 2
3
- ..100257 44 56 4
3
.135052
sensitivity
coefficient
a
one
percent
change
in
the
voltages
are
parameter value;
Worst
NODE NO.
a
representing the change in node voitage
case
node
computed at lines 2240 to 2310. Lines 2240
to 2280 produce toierance values with
m a x i m u m tolerances being positive and
.0270103
m i n i m u m tolerances negative. A worst
NODE VOLTAGES WITH RESPECT TO VOLTAGE SOURCE IN BRANCH 4
case m a x i m u m vaiue is computed as the
sum of the products of partial derivatives
NODE NO.
PARTIALS
2t
- .30. 3
68
98
00
86
97
3
.945336
SENSITIVITIES
and toierance values when both terms
-1
. 0. 91 48043534E5- 0 4
are positive. A m i n i m u m vaiue is the
sum
4.72678E-03
when
both t e r m s are
Assuming that the partia!
negative.
derivatives
are nearly constant over the toierance
*WORST CASE NODE VOLTAGES*
range, the worst case analysis is within
NODE NO.
NOMINAL CASE
1
2
3
2.797
42
28
3
21.12. 60 8
53
W . C . MAX
3 . 2 85
01
69
21.57. 51 8
74
W.C.
MIN
about three percent of actual values, in
2 .. 9
314
021
6
1 . 77
8 19
67
3
other wor(js, keeping tolerance values
small (10% or less) keeps the worst case
analysis within three percent of actual
*STANDARD DEVIATION OF MODE VOLTAGES*
NODE MO.
STD.
1
2
3
DEV.
.0896619
.555564
.0883014
values.
If larger tolerances need to be used
or more accurate results are desired, use
direct substitution of
partial
RUN
? R MO MORE TO DO
? END
minimum/maxi-
m u m values according to the sign of the
derivative
again.
procedure
in a M O D I F Y
Be s u r e to r e p e a t
for each
parameter.
and
the
The
anaiysis used in this program has the
advantage of giving results directly from
the nominal solution.
CONTINUED
C/N Juna.
1377
TWENTY-ONE
Lines
standard
based
2320
to
deviation
on
partial
2330
compute
of node
a
voltages
derivatives
and
tolerance values.
The
sample
solutions
that
foiiow
were run on an Aitair 8800b with 16K
memory.
I used
Aitair
8K
BASiC
(versions 3.2 and 4.0) with some m e m o r y
to spare.
Processing an input line of branch
data requires about three to 10 seconds,
depending on the n u m b e r of values. The
complete output in the s a m p l e run took
about 15 minutes to print on a 110 baud
terminal. By using 4.0 BASiC, input can
easily be saved for large circuits.
Readers
who a r e u n f a m i i i a r
with
etectronic circuit analysis should look for
a
simpie
electrical
engineering
or
network anaiysis text.
For
more
applications,
TRONIC
GRAM
information
read
CIRCUIT
(ECAP;
IBM's
1620
ANALYSiS
1620-EE-02X)
on
ELECPRO-
USER'S
M A N U A L (publication n u m b e r H20-01701)
or
iBM
ANALYSIS
AND
ELECTRONiC
PROGRAM
APPLICATIONS,
Lieberman,
CIRCUiT
TECHNIQUES
Jenren
Prentice-Hall,
Englewood Cliffs, N . J .
Table 1
Available Output
NV
Node voltages
BV
Branch voltages
EV
E l e m e n t voltages
BC
Branch currents
EC
Element currents
PL
E l e m e n t power losses
PD
Partial derivatives
WC
Worst case analysis
SD
Standard deviation
CM
Nodal conductance m a t r i x
IM
Nodal impedance m a t r i x
CV
Equivalent current vector
ALL
All the above
and
Inc.,
Variable
list
M O - M o d i f y flag
MN - M a x i m u m n o d e s
MB - M a x i m u m b r a n c h e s
MD - Maximum dependent sources
M(MB,MN) - Connectivity matrix
N I ( M B ) - I n i t i a l n o d e of b r a n c h ME
N F ( M B ) - F i n a l n o d e of b r a n c h MB
Z{MN+1,MN+1) - N o d a l conductance matrix
Nodal impedance matrix
Y ( M B ) - C o n d u c t a n c e in b r a n c h M B
Y L ( M B ) - M i n i m u m c o n d u c t a n c e in b r a n c h M B
Y H ( M B ) - M a x i m u m c o n d u c t a n c e in b r a n c h M B
C U ( M B ) - C u r r e n t in b r a n c h MB
A ( M B ) - N o m i n a l c u r r e n t s o u r c e in b r a n c h MB
AL(MB) - Minimum
"
"
AH(MB) - Maximum
"
E ( M B ) - N o m i n a l v o l t a g e s o u r c e in b r a n c h MB
EL(MB) - Minimum
"
"
EH(MB) - Maximum
"
"
D(MB) - N o m i n a l t r a n s c o n d u c t a n c e in b r a n c h MB
DL(MB) - Minimum
DH(MB) - Maximum
"
E Q ( M N ) - E q u i v a l e n t c u r r e n t v e c t o r for n o d e MN
IP(MN) - C o u n t e r s for m a t r i x i n v e r s i o n
I N ( M N , 1 ) - S u b s c r i p t s of m a t r i x Z s h o w i n g M a x i m u m v a l u e s
N V ( M N ) - N o d e v o l t a g e of n o d e MN
B V ( M B ) - B r a n c h v o l t a g e of b r a n c h M B
W(MN) - Nominal node voltages
WL(MN) - Worst case minimum node voltages
MH(MN) "
"
maximum
"
"
R W ( M D ) - R e s i d i n g b r a n c h of d e p e n d e n t s o u r c e
C L ( M D ) - C o n t r o l l i n g b r a n c h of d e p e n d e n t c u r r e n t s o u r c e
SD(MN) - S t a n d a r d d e v i a t i o n of n o d e v o l t a g e s s q u a r e d
D $ , K $ , C $ , P $ - c o m p a r i s o n c h a r a c t e r s for i n p u t
KM,KP,K1,K2,K3,K4,K5,K6,K7,K9,PC,CT,CM,CI,S6 - constants
NN - N u m b e r o f n o d e s in this c u r c u i t
NB "
" branches "
NY "
" r e s i s t a n c e s ( c o n d u c t a n c e s ) in this c u r c u i t
NE "
" v o l t a g e s o u r c e s in t h i s c i r c u i t
NA "
" i n d e p e n d e n t c u r r e n t s o u r c e s in t h i s c i r c u i t
PR - output flags
X$ - input line
L - L e n g t h of X $
I - C h a r a c t e r p o i n t e r in X $ , L o o p v a r i a b l e
J , K , L , M , N , L 1 , I T , I I , J J - loop v a r i a b l e s
TY - T y p e of c u r r e n t i n p u t line
X - p r e s e n t b r a n c h or d e p e n d e n t s o u r c e n u m b e r
T - Temporary nominal value
TL "
minimum
"
TH "
maximum
"
T T - T y p e of c u r r e n t p a r a m e t e r
NI,NF,T1,T2 Temporary variables
ZZ - R e t u r n flag for s u b r o u t i n e 600
MU - Multiplier value
L A - L a s t v a l u e t o be p r i n t e d on this line
PV - current pivot
24V
12
BC = branch current
TWENTY-TWO
C / N Jurte, 1 9 7 7
by locations F F F E and F F F F resets the
ACIA
630b
isoiating problems in the Aitair 680b
is
sometimes
interaction
difficult
between
due
to
hardware
would
and
Location
then
jump
examines
of h a r d w a r e
to 0000 instead
location
F002.
F002 is the a d d r e s s of the
programmable
the
outputting to the t e r m i n a l . Bad m e m o r y , t e r m i n a l / n o
and
particularly in locations 00F3-00FF, can
bits
terminal,
(i.e.
Baudot/no
Baudot, etc.). The M P U stores this bit
software. The Aitair 680b m a y fai! to
throw the M P U off (the stack pointer is pattern f r o m location F002 along with
operate for several
Bit 7 of
stored in one of these locations). If the other information into locations OOF3-
location F002 m i g h t be high and the 6800
6800 can't access the proper instructions O O F F . If bit 7 ( t e r m i n a l / n o t e r m i n a l ) is
reasons.
.from the P R O M monitor, the 680b can go high, the M P U branches to iocation 8000
into a wild run condition. Finally, if the and starts execution. If bit 7 is low, the
ACiA
the M P U examines the n u m b e r of stop bits
isn't initialized or working,
indicated by location F002 and sends this
680b m a y not output.
Troubleshooting
these
problems
for information to the A C I A . When the A C i A
procedures
are
covered
this is Ready to output, the M P U then outputs
in
article, following a brief expianation of the p r o m p t character.
the Reset and Monitor operations during Troubieshooting
1. Halt the 680b and e x a m i n e location
Reset. (The Baudot option monitor is not
_12
here. However, those users F002. Data bits 5 and 6 should be high.
described
with the Baudot option should be able to D a t a
bits
1, 2, 3, 4 a n d
apply this information to their systems.) c o r r e s p o n d
6800
microprocessor
can
option is set.
be
p r o g r a m m e d to start executing at any
memory
iocation.
This
differs
b. Bit 2 will be low if 2 stop bits are
signif-
set and high for 1 stop bit.
icantly f r o m the 8080 microprocessor, in
-Vs
T
which
2K
the
8080 p r o g r a m
counter
c. Bits 3 and 4 are not used and a r e
is
n o r m a l l y set low.
cieared with reset and execution starts at
6K
location 0. The 6800 is reset when R E S
d. Bit
(reset - pin 40 of the 6800) is low for eight
retrieving
the
contents
of
IK
information
into
the
program
counter.
The
then
starts
execution
at
unit
(MPU)
the
location
indicated by the p r o g r a m counter. Notice
that in the Aitair 680b, locations F F F E
a n d F F F F a r e located inside the P R O M
N0
monitor.
20
When
T
[3
the
6800
microprocessor
is
hatted and the Reset switch is held, V M A
is tow, BA and
?2K
R/W
are high
(read
state), and the address bus contains the
restart address F F F E . Address
N2
lights
A1-A1S are then on, and the AO tight is off
6E
when the Reset switch is held. When the
B
R u n / H a l t switch is moved to Run, the
11. IK
Dl
from
FFFE
and
FFFF,
part of the p r o g r a m counter and the byte
ijp
ET
reads
storing the byte in F F F E in the upper
/
IK
6800
N3
Bj
Loo
in location F F F F in the lower part of the
p r o g r a m counter. The 6800 then j u m p s to
the location pointed to by F F F E
EJ
FFFF.
-i-W
*r* N0
C / N J u n e . 1 9 7 7 ONE
and
Monitor Operation During Reset
termlnai
If the data lights do not m a t c h the
above list, check for shorts and bad iCs.
IC R R should be enabled with a low at
pins
microprocessing
be low for
option.
memory
iocation F F F E and F F F F and loading
7 will
option and high for no t e r m i n a l
clock periods. A reset operation invoives
this
7 should
hardware-
a. Bit 1 will be low if the no Baudot
After the Aitair 680b is powered up,
- J r
the
p r o g r a m m a b l e straps set by the user.
Reset
the
to
1 and
15. The inputs of
iC
RR
correspond to the h a r d w a r e straps. If IC
R R is not enabled IC X is usually at fault.
2. Try the 680b first in no terminal
option with the foliowing j u m p routine.
Jump
0000
7E
1
00
2
-amp
00
If
the
680b f a i l s
to e x e c u t e
it
properly, e x a m i n e all the locations in the
PROM,
FFFE
particularly
and
locations
FFD8-FFF4.
FFFF,
The data
in
these locations should match the listing
given in the System Monitor M a n u a l . If
not, do the following.
a. Check address gating at pin 14
(chip
select)
for
the
PROM.
E x a m i n i n g addresses f r o m FF00F F F F should result in a low at pin
14.
* When running, only AO & 1 should be lit.
When the 6800 starts executing the
CONTINUED
instructions, the instructions pointed to
TWENTY-THREE
M a w
CONTINUED
T e c h n i q u e s
b. Check each address line on the
tocation 000B. This p r o g r a m is designed
components or if the A C t A is not reset
P R O M by separately lifting u p A0-
to be run when the 680b is strapped for no
with software.
A7 and
terminal
monitoring
the
PROM
which
7. Users with 680b-BSM cards who
address pins. If a line fails to go
activate the A C t A can be seen. Notice
a r e trying to check the write w a v e f o r m s
high
with
the
address
switch,
so
that
the
inputs
that if 41 is in tocation 000B, the tetter U is
can use any p r o g r a m that continuously
check for shorts. Shorts between
output. The A S C i )
writes into m e m o r y .
address
letter
lines can
be found
by
bit pattern for the
U is 01010101, resulting
in
an
The p r o g r a m
usuatty put in the working
IK
is
RAM.
trying combinations of addresses.
atmost s y m m e t r i c a l square w a v e at pin 6
Tabte 5 contains a p r o g r a m that witt
c. Check the power and ground to the
of the A C I A . Any putses or levels which
write whatever is in tocation 0001 into an
P R O M . Note that the -9v shoutd be
do not m a t c h Table 1 indicate a problem.
address of the 680b-BSM card.
at least -9v at the bottom of the
5. The 680b m a y
ripple.
d. Check the data f r o m the P R O M
letter or p r o m p t character if the 6800
the
microprocessor
INTRODUCTtON
TO
COMPUTERS
Osborne
and the data buffers W W and Y Y .
register futt
These buffers shouid be enabled.
status
e. Chip select
RAMs)
(pin
should
13 of the 2102
not
be
low
ACtA
address FFOO-FFFF.
sees a
The
looping,
to indicate that
transmit.
transmit
indication
register.
continuousty
for
The
by t h e
data
ACtA
MPU
may
be
waiting
for
the
it is ready
program
in
Table
to
3
deposits the status in tocation 0020 since
f. The M P U R / W line should be high
when the 680b is halted. Check the
it cannot be checked when the 680b isn't
halt state levels of the 6800 as
running.
shown in the following list.
For further repair probtems, contact
never output the
MtTS
Associates
PUTER
Repair
and
SYSTEM
Department.
by
M6800
AN
MICROand
MtCROCOM-
DESiGN
DATA
by
Motorota a r e atso excel tent references on
the operation of the 6800 and its f a m i l y of
chips.
R u n the p r o g r a m for a m o m e n t , then
stop the 680b and e x a m i n e tocation 0020.
Data bit 1 shoutd be high, indicating a
ready to t r a n s m i t condition, and data bit
0 shoutd be tow if no data has been sent to
the 680b. D a t a bits 2 and 3 shoutd be tow.
tf incorrect, check to see if A C t A pins 23
and 24 a r e low (which they should be), tf
bit 1 is low, the A C t A was not reset
RAM
property. Check the data tines f r o m the
m e m o r y exists in location 0000-00FF by
6800 to the A C t A for shorts or opens
3. M a k e
depositing
sure t h a t w o r k i n g
into
each
bit
separateiy.
(especially
D O and
D l ) „ Recheck the
Locations 00F2-00FF a r e used by the
signals to the A C t A . Highs in bits 4, 5 an{t
PROM
6 indicate transmission errors.
bytes
monitor
such
echo/no
as
echo
for
various
breakpoint
and
the
software
address,
6. tf the A C t A w!tt output but not
pointer.
input, run the p r o g r a m in Tabte 3 a n d
stack
M a k e sure that these tocations work and
check
are separate f r o m all other locations by
printing periods for proper tetters typed
the status,
tf the 680b
keeps
iifting up each address switch one at a
to it (like M , N or J ) , then the ASCtt
t i m e and checking to see if only the
codes
corresponding
for
these tetters a r e
probabty
lights. If an
LED
distorted. The p r o g r a m in Tabte 4 can
does not light, check for shorts.
(For
hetp isolate this problem.
information
LED
on deposit
problems,
see
"Troubleshooting the 680b," September
CN, pp. 6-7 and 10^
4. Unfortunately,
W h i l e running the p r o g r a m , type one
character on the t e r m i n a i . Stop the 680b
and e x a m i n e tocation 0020. C o m p a r e the
the
AC IA
status
bit pattern on the data tights to the ASC11
and data register can't be checked with
code for that character, tf they do not
the 680b in the halt state, because V M A is
m a t c h , took for shorts on the data lines.
low when the M P U is hatted, if the A C t A
Pin 2 of the A C t A shoutd go tow when the
is not reset property or given correct
character is typed, otherwise check t/0
seriai
wiring, tf pin 2 of the A C t A is atways tow,
information,
the 680b m a y
not
output the prompt character.
the A C t A witt think it is atways Receiving
Check the inputs to the ACtA for the
a character, tf a TetetypeTM is used as
halted state as listed in Table 1. Tabte 2
the t/0 terminat, it wit! run open. Pin 2
shows a p r o g r a m which initializes the
coutd be tow permanentty due to shorts,
ACiA
improper
and
character
constantly
whose
TWENTY-FOUR
ASCI)
outputs
code
the
is
in
ptacement
of
components
(check R204 if TTY is used), bad
t/0
C / N J u n e . 1 9 7 7 ONE
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Have you written Software
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The Aitair 8 8 0 0 c o m p u t e r was the first micro
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and its rapid adaptation to many diversified applications has truly turned the dream of the affordable
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That's w h e r e you c o m e in. The A S D C will pay
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design, coding and d o c u m e n t a t i o n . The software
will then be further
d o c u m e n t e d and distributed through
^ ^ ^ ^ ^ ^ ^
Aitair Computer Centers around ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ the country.
For more
information
on h o w to
^ H H H ) ^ ^ ^ ^ submit software to
the A S D C , H
HHHHH) H
ask your Local
A l t a i r C o m ^ y ^ ^ t ^ y ^ ^ p u t e r Center for an
ASDC
Software Submittal
or contact the ALTAIR
W A R E DISTRIBUTION
COMPANY.
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