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OOQOThe  Boston  Computer  Society 

SINCLAIR-TIMEX  USER  GROUP  NEWSLETTER 

Volume  2,  Issue  5  May  1983 


This  newsletter  is  produced  to  inform  group  members  of  the  agenda  and 
logistics  for  future  meetings,  as  well  as  to  recap  and  amplify  the  information 
provided  at  the  last  meeting.  It  also  provides  a  forum  for  members  and 
interested  parties  to  communicate  what  they  have  learned  or  developed  relating 
to  Sinclair  and  Timex  computer  products.  Meetings  are  open  to  the  public; 
however,  attendees  are  encouraged  to  join  the  Boston  Computer  Society  (BCS). 
This  newsletter  is  free  to  members.  Back  issues  are  one  dollar  each. 


USER  GROUP  MEETING 

Date:  Wednesday,  May  18,  1983 

Time:  7:00  p.m. 

Place:  Large  Science  Auditorium 

UMass,  Harbor  Campus 
(Directions  on  last  page) 


At  the  May  meeting,  Dan  Roy  will  unveil  the  add-on  color  capability  for 
the  T/S-1000.  The  product  he  developed  is  called  C0L0RSIN81.  It  features  a 
high-resolution  color  display,  sound,  joy  stick  interface,  and  an  expansion 
capability  via  a  6-slot  motherboard.  Display  features  include  three  modes  of 
high-resolution  color  and  a  text  mode  with  24  lines,  40  characters  per  line. 
There  are  powerful  new  commands,  such  as  DATA,  READ,  RESTORE,  block  moves,  and 
plotting  subroutines.  All  this  for  only  $159.95  as  a  kit.  In  addition,  Dan 
will  demonstrate  the  CAI/EXATRON  stringy  floppy  mass  storage  device.  Dan  says 
that  the  stringy  floppy  was  essential  for  the  development  of  C0L0RSIN81.  With 
the  stringy  floppy,  one  can  load  a  16  K  program  in  about  15  seconds.  Numerous 
features,  such  as  the  capability  to  chain  programs,  are  included  in  this 
system. 

Following  Dan's  presentations,  we  will  break  into  groups  to  discuss 
topics  of  interest.  Tentatively,  an  advanced  and  a  beginner's  group  are 
planned . 

At  the  June  meeting,  Dave  Miller  will  demostrate  and  explain  QSAVE  and 
FASTLOAD — programs  which  are  available  from  Gladstone.  If  you  have  items  to 
discuss  at  a  future  meeting  or  suggestions  for  presentations,  contact  Sue  or 
Cliff. 


WHAT'S  DIFFERENT  ABOUT  THIS  NEWSLETTER? 

Don't  worry,  we'll  tell  you.  This  issue  contains  advertising. 
Advertising  helps  offset  the  cost  of  publication  and  debuts  product 
information  which  may  be  of  interest.  We  have  established  a  few  basic  rules 
to  help  guide  us  in  this  area.  Anyone  who  is  interested  in  these  guidelines 
or  has  suggestions  contact  Jack  Hodgson,  Publisher. 


HIGHLIGHTS  OF  THE  APRIL  MEETING 


As  with  the  past  several  meetings,  the  April  meeting  was  jam-packed  with 
activity — demonstrations,  hardware  and  software  discussions,  and  hints. 

Sue  Mahoney  began  the  meeting  with  a  demonstration  of  "Ator  the  ABC 
Gator.”  Ator  is  a  Timex  program  which  synchronizes  a  fanciful  display  of  the 
letters  of  the  alphabet  with  a  song  recorded  on  the  cassette  tape  containing 
the  program.  Simple  procedures  for  synchronizing  the  computer  and  tape  are 
included  in  the  program.  When  synchronized,  the  computer  flashes  letters  on 
the  screen  as  the  author  sings  her  song.  Ator  is  designed  to  teach  the  ABCs 
to  preschoolers.  It's  interesting  to  note  in  passing  that  Ator,  as  other  ABC 
songs,  contains  that  long  letter  in  the  center  of  the  alphabet  with  which  many 
kids  have  trouble,  namely  LMNOP. 

Following  Sue's  presentation,  Dave  Wood  demonstrated  the  new  printer  he 
purchased  and  interfaced  with  his  computer,  the  Okidata  Microline  92.  He 
described  his  initial  interfacing  difficulties  and  how  these  were  resolved 
(contact  Dave  to  save  yourself  these  problems).  He  also  described  some  of  the 
software  he  developed  to  use  with  the  printer.  See  Dave's  article  on  page  4. 

Gene  Bachman  showed  some  pictures  of  spectra  and  waveforms  taken  from 
several  tape  recorders  which  illustrated  differences  between  different 
recorders.  See  Gene's  article  below. 

A1  Spencer  reviewed  the  Parrot  by  R.I.S.T.  Computer  Components,  Inc., 

P.0.  Box  499,  Fort  Hamilton  Station,  NY  11209.  The  Parrot  is  a  voice 
synthesis  module  which  plugs  into  the  edge  connector  of  our  computer.  When 
the  computer  commands,  the  Parrot  speaks  in  allophones.  You  must  supply  a 
speaker.  By  using  the  proper  sequence  of  allophones,  speech  is  generated.  A1 
played  a  tape  with  several  sentences  spoken  by  the  Parrot — all  were 
understandable.  The  Parrot  costs  $89.95  plus  $4  shipping  and  handling. 

Also  at  the  meeting,  a  number  of  shorter  items  were  covered.  Mike 
Coughlin  suggested  a  new  way  to  avoid  RAM  pack  wobble.  His  solution  involves 
installing  an  HM6264  8  by  64  K  memory  chip  in  the  computer.  Sue  distributed 
the  first  issue  of  Ramb lings ,  the  Timex  Computer  Club  newsletter.  Sue  also 
awarded  Cliff  Danielson  and  John  Kemeny  Timex  T-shirts  for  their  efforts  on 
the  newsletter.  Will  Stackman  suggested  the  use  of  a  Radio  Shack  75  ohm 
auto-duplication  coaxial  cable  for  replacing  the  cable  between  the  computer 
and  the  television. 


A  COMPARISON  OF  THREE  RECORDERS  by  Gene  Bachman 

I  began  having  loading  problems  after  I  dropped  my  Radio  Shack  recorder 
down  the  stairs.  While  it  was  in  for  repairs,  I  switched  to  a  10  year  old, 

$19  Montgoraery-Ward  portable.  The  Montgomery-Ward  wouldn't  load  at  all  until 
I  installed  a  10  ohm  resistor  across  the  earphone  jack.  I  also  noticed  a  loud 
background  hiss  when  listening  to  a  program.  Timex'  instructions  say  the 
computer  needs  4  volts  peak-to-peak  from  the  recorder.  I  measured  the  output 
of  the  recorder  with  a  digital  voltmeter  at  less  than  one  volt.  This  was 
because  the  voltmeter  measures  an  average,  not  peak-to-peak,  voltage.  When 
the  damaged  Radio  Shack  recorder  was  returned,  it  was  very  unreliable.  It  had 
a  hiss,  which  it  did  not  have  before,  and  the  speed  wavered.  At  this  point,  I 
decided  to  see  just  what  made  a  recorder  good  or  bad. 

I  played  the  same  program  (Psion  flight  simulator)  on  my  two  recorders 
and  on  a  Sony  instrumentation  recorder  into  a  frequency  spectrum  analyzer.  I 
have  access  to  a  laboratory  with  such  equipment.  The  three  spectra  computed 


THREE  RECORDERS  (Continued) 


from  256  samples  of  each  signal,  were  so  similar  that  no  conclusions  could  be 
drawn  (see  frequency  spectrum  figure).  Since  I  couldn't  make  much  sense  of 
the  voltmeter  readings  or  spectra,  I  finally  resorted  to  the  old  reliable 
oscilloscope,  in  this  case,  a  Tektronix  storage  scope. 

With  the  Sony  recorder  and  a  laboratory-grade  decade  amplifier,  I 
generated  a  4  volt  peak-to-peak  signal.  The  computer  liked  this.  It  loaded 
every  program,  every  time.  Looking  at  the  signal  on  the  oscilloscope,  I  could 
see  short  and  long  tone  bursts  obviously  representing  zeros  and  ones. 

Increasing  the  horizontal  scale  to  1  millisecond  (ms)  per  division  allowed  me 
to  count  the  number  of  cycles  in  the  bursts  and  to  measure  the  frequency  of 
the  tone.  Four  cycles  of  a  3.33  kHz  tone  represented  a  zero;  nine  cycles  a 
one.  The  total  time  to  transmit  a  zero,  that  is,  the  length  of  the  tone  burst 
plus  dead  time  between  two  bursts,  was  2.5  ms.  This  is  a  signaling  rate  of 
400  baud,  that  is,  400  zeros  can  be  transmitted  in  one  second.  The  ones 
occupied  4.0  ms  for  a  signaling  rate  of  250  baud.  I  was  not  able  to  discern 
the  beginning  or  end  of  a  byte;  spaces  between  bits  and  bytes  looked  identical. 

Now  that  I  knew  what  the  signal  should  look  like,  I  played  the  program  on 
the  old  cheap  recorder  and  on  the  damaged  one.  The  differences  were  obvious 
(see  figures).  Whereas  the  Sony  signal  was  clean  and  symmetrical,  the 
Montgomery-Ward  was  distorted  and  unsymmetrical .  The  Radio  Shack  signal  was 
even  more  distorted,  due,  I  suspect,  to  a  bent  drive  shaft  and  misaligned 
heads . 

From  my  experience,  I  conclude  that  if  a  recorder  set  at  3/4  of  full 
volume  has  a  lot  of  hiss  when  playing  a  new,  unrecorded  tape  or  has  a  wavering 
or  tinny  sound  when  playing  music,  it  will  send  the  computer  a  distorted 
signal.  This  makes  it  unreliable,  even  when  loading  tapes  that  were  saved  to 
the  same  recorder.  On  my  way  home  from  the  laboratory,  I  bought  a  new 
Panasonic  model  RQ2735  and  have  had  no  more  problems. 


20  dB 


( - - ^ 

FREQUENCY  SPECTRUM 

w 

V _ ) 


INTERFACING  A  REAL  PRINTER  TO  THE  TIMEX/ SINCLAIR  1000  by  Dave  Wood 


This  article  describes  how  I 
attached  an  Okidata  Microline  92 
dot-matrix  printer  to  ray  MicroAce 
computer,  (The  MicroAce  is  a  copy  of 
the  ZX-80  computer  which  I  have  modified 
to  be  equivalent  to  the  T/S  1000.)  I 
purchased  the  Okidata  printer  because  of 
its  versatility  and  print  fidelity.  For 
the  money  ($500-$600),  one  can  get  very 
good  type  quality,  almost  like  an  impact 
printer.  The  Okidata  can  print  at  10, 
12,  and  17  characters  per  inch.  It  can 
also  print  double  width  characters  with 
each  pitch.  It  will  accept  up  to  64 
user-defined  characters.  This  could  be 
used  to  generate  most  of  the  Sinclair 
characters.  The  printer  can  also  print 
individual  dots  for  graphics  output. 


This  is  an  example  of  the  qua 
ABCDEFGHI JKLMNOPQRSTUVWXYZabcdef 

This  Is  Enhanced  Printing. 

This  Is  Emphasized  Printing. 

This  is  printed  at  17  characters  cer  inch,  which  permit 
It  is  also  possible  to  pr intsu^erscr^- 

Double  Width  Characters 

Example  of  Print  Quality 


Electrical/Logical  Interface  with  the  Printer 


The  printer  comes  equipped  with  a  "standard"  Centronics-compatible 
parallel  interface.  Exactly  what  Centronics-compatible  means  is  not 
immediately  obvious.  As  I  finally  figured  out,  there  are  three  important 
elements  in  this  interface.  First,  8-bit  characters  are  passed  to  the  printer 
on  eight  parallel  data  lines  (one  bit  per  wire).  Second,  an  input  strobe  line 
notifies  the  printer  when  the  data  (the  8-bit  character)  is  ready  on  the 
parallel  data  input  lines.  The  strobe  line  is  normally  held  at  logical  one 
(+5  volts).  When  the  data  is  ready,  the  signal  on  the  strobe  line  should  go 
to  logical  zero  (0  volts)  for  a  microsecond  or  so  and  then  return  to  a  logical 
one.  The  data  is  actually  accepted  by  the  printer  on  the  rising  edge  of  this 
strobe  pulse,  i.e.,  when  the  signal  level  goes  back  to  one.  The  third  element 
is  a  busy  output  line  which  notifies  the  computer  that  the  printer  doesn't 
want  to  get  any  new  data.  The  second  and  third  items  constitute  the  handshake 
protocol  by  which  the  computer  and  the  printer  agree  on  sharing  the  character 
data . 


My  computer  is  equipped  with  the  CAI/0  Board  interface  from  CAI 
Instruments,  Midland,  Minnesota,  which  has,  among  other  things,  three  8-bit 
parallel  input/output  ports.  This  interface  can  be  configured  (programmed)  to 
operate  in  different  modes.  The  interface  is  memory  mapped,  so  that 
programming  it  or  writing  to  an  output  port  is  accomplished  by  POKEing  to 
specific  addresses  and  reading  an  input  is  accomplished  by  PEEKing.  The 
automatic  parallel  interface  mode  of  the  CAI/0  interface,  which  has  built-in 
handshaking,  was  an  obvious  choice  to  use  for  the  printer  interface.  Wrong! 

It  is  not  Centronics  compatible.  Thus,  I  had  to  use  the  CAI/0  interface  as  a 
simple  (dumb)  interface,  providing  the  proper  handshake  protocol  by  software 
in  my  computer. 

I  configured  the  three  ports  on  the  CAI/0  interface  as  12  bits  out  (8 
bits  of  port  A  for  data  and  4  bits  of  port  C  for  control)  and  12  bits  in  (8 
bits  of  port  B  for  printer  signals  and  the  other  4  bits  of  port  C  unused). 

The  actual  wiring  of  the  cable  between  the  Centronics-compatible  connector  at 
the  printer  and  the  dual-15  edge  connector  on  the  CAI/0  interface  creates  the 
mapping  of  bits  between  the  computer  and  the  printer.  Most  of  these  bit 
assignments,  with  the  exception  of  the  port  A  data  lines,  were  arbitrarily 
chosen. 


Software  Interface  with  the  Printer 


At  first  I  implemented  the  software  interface  in  BASIC.  But  the  program 
was  uncomfortably  slow.  So  I  wrote  the  program  in  machine  language.  The 
machine  language  program  occupied  only  242  bytes,  including  the  ASCII 
conversion  table.  To  pass  a  character  to  the  machine  language  program,  I  used 
a  fixed  memory  location.  In  this  straight-forward  approach,  you  POKE  from 
BASIC  and  read  from  the  location  in  the  machine  language  program.  I  used  the 
fixed  address  16506  in  the  system  variables  area.  My  machine  language 
program,  which  handles  the  ASCII  conversion  and  handshake  protocol  is  located 
at  32525.  Thus,  sending  a  character  to  the  printer  consists  of: 

POKE  16506,  (character  code)  followed  by  RAND  USR  32525. 

Conceptually,  translation  from  Sinclair  character  codes  to  ASCII  can  be 
handled  as  a  table  look  up.  In  other  words,  one  could  place  in  RAM  a  table  of 
256  ASCII  characters  which  correspond  to  the  256  Sinclair  characters,  then 
simply  use  the  Sinclair  character  code  to  index  into  the  table.  However,  a 
bit  more  thought  is  required.  Some  judgment  must  be  used,  for  example,  to 
decide  how  to  map  to  the  ASCII  characters  !,  ',  #,  @,  and  others.  There  are 
only  128  ASCII  characters  defined;  also  only  128  of  the  Sinclair  characters 
are  printable.  My  conversion  program  allows  me  to  treat  either  normal  or 
inverse  vedio  alphabet  as  the  lower  case  ASCII  characters. 

The  Centronics  handshake  protocol  is  simple  to  implement,  as  the  program 
below  demonstrates.  An  important  part  of  this  code  is  use  of  ROM  routines  to 
test  for  and  act  upon  the  break  key.  Testing  for  the  break  key  allows  one  to 
escape  from  the  machine  code  and  not  be  trapped  in  "never-never  land"  should 
the  printer  hang  up. 


{Enter  with  ASCII  character  in  A  reg.} 


{  DELAY  UNTIL  PRINTER  READY  } 

{Set  HL  with  input  port(B)  address.  } 
PRINT  LD  HL, 3C01h 
{Test  to  see  if  printer  is  busy.  } 

TSTB  BIT  0 , (HL) 

JR  Z , OK 

{Save  the  character  in  A  register.  } 
PUSH  AF 

{Check  for  break  key.  } 

CALL  0F46h 

{If  break,  exit  to  "D"  return  code.  } 
JP  NC,03A6h 


{Recall  the  char.&  see  if  still  busy.} 
POP  AF 
JR  TSTB 

{  OUTPUT  CHARACTER  AND  STROBE  } 

{Change  HL  to  output  port(A)  address.} 
OK  DEC  HL 

{Output  the  character.  } 

LD  (HL) , A 

{Change  HL  to  port  C  address.  } 

INC  HL 
INC  HL 

{Strobe  -  set  bit  7  low,  then  high.  } 
RES  7 , (HL) 

SET  7 , (HL) 

RET 


ts  1000.  ZX81.  8K  ROM  ZX80  2K  memorv  or 


|  hey/thereT) 


A  cassette  of  two  display  programs. 


TS  1000.  ZXB1  8K  ROM  ZX80  2K  m 


ESCAPE  FROM  STALAG  LUFT  III 


A  slialegy  game  by  Sieve  Barrett  As  a  COW  you  must  make  disguises  tortje 
papers  dig  tunnels  1'irJe  wnecutteis  watch  guards  distract  wjlchtowms  am!  at 
lire  nghi  moment  attempt  escapes  After  concealing  your  preparations  trout  tench 
and  barracks  searches  watch  your  blit/outs  occur  on  an  overhead  view  ol  Hit 
camp  Compound  gale,  lowei  and  perimeter  guards  are  all  wailing  to  halt  you  wit 
a  cud  German  phrase  and  escod  you  oil  to  lire  cooler  Guard  sl'dlogy  is  stored 
"The  Brain  Will  you  play  against  the  kindly  Hauptmann  Reuss  m  Itie  ictenlU-  -• 
and  lemorseless  Kommandanl  von  dm  Erche7 


Our  catalog,  with  screen  display 
and  coding  sheets,  is  free! 


THE  FANTASTIC  MUSIC  MACHINE 


SIMULUSION,  BOX  894,  LEMON  GROVE,  CA  92045 


THE  TIMEX/ SINCLAIR  AS  AN  INTELLIGENT  LAB  STATION  TERMINAL  by  Larry  Becker 


Imagine  a  science  laboratory 
with  up  to  16  stations,  each 
containing  a  computer  capable  of 
instrument  control  as  well  as  analog 
and  digital  data  collection.  Each 
lab  station  computer  could  either 
display  the  data  as  they  are  being 
received  or  store  the  data.  The 
stored  data  could  then  be  sent  to  a 
larger  computer  for  storage  on  disk 
and  later  analysis  and  display.  The 
incoming  data  at  the  lab  station 
could  be  sampled  at  selectable  time 
intervals  or,  alternatively,  sampled 
at  the  request  of  an  external  signal. 

In  addition,  the  lab  station  could 
generate  digital  or  analog  signals 
for  control  of  stepper  motors  or 
voltage-controlled  instrumentation  used  in  experiments.  A  nice  thought,  you 
say  ...  but,  oh,  the  expense! 


Now  suppose  that  each  lab  station  costs  no  more  than  $300  (including  the 
computer,  computer  memory,  interfacing  hardware,  and  CRT  monitor);  and  the 
large  host  computer  with  which  the  lab  station  communicates  was  an  unmodified 
Apple  computer.  Interested? 


During  the  past  few  months  at  Technical  Education  Research  Centers 
(TERC) ,  while  on  sabbatical  leave  from  the  Physics  Department  of  Hiram 
College,  I  have  been  developing  the  hardware  and  software  which  will  turn  the 
Timex/ Sinclair  microcomputer  into  the  intelligent  lab  station  described  above. 
The  T/S  1000  with  16  K  memory  pack  can  be  purchased  for  under  $100.  A  small 
black  and  white  television  costs  less  than  $100.  The  interface  hardware  which 
allows  the  above  capabilities  has  been  built  and  thoroughly  tested.  And  an 
initial  software  capability  has  been  developed.  The  hardware  and 
user-friendly  software  should  not  cost  more  than  $100.  A  $300  lab  station  is 
feasible. 


The  prototype  interfacing  board  (see  figure  1)  measures  7-1/2  by  5-1/2 
inches.  It  should  be  possible  to  reduce  the  size  to  about  4  by  5  inches. 

Consequently,  not  only  will  the  cost  be 
low,  but  also  the  size  will  be  such  as  to 
take  up  very  little  space  at  the  lab 
station.  The  television  monitor  will  be 
the  biggest  part  of  the  system. 

Preliminary  software  includes  four 
programs.  The  first  program  displays  the 
voltage  levels  on  two  of  the  eight  analog 
input  channels  of  the  interface  board  (see 
figure  2).  A  marker  on  the  voltage  line 
for  each  channel  moves  back  and  forth  as 
the  level  is  changed .  A  program  such  as 
this  would  be  helpful  during  experiment 
set-up  to  determine  if  the  voltage  levels 
from  the  equipment  are  within  the  0  to  5 
volt  range  needed  for  the  interface 
circuitry. 


INTELLIGENT  LAB  STATION  (Continued) 


The  second  program  samples  the  input  voltages  and  plots  the  values  on  a  time 
axis  while  the  voltage  is  varying.  For  example,  it  generates  a  sine  curve  on 
the  monitor  as  a  potentiometer  is  rotated  by  a  swinging  pendulum.  In  its 
present  form,  the  program  plots  the  curve  with  32  large  squares.  Double  this 
resolution  is  possible.  A  curve  made  up  of  64  data  points,  however,  is  still 
much  too  coarse  for  most  experiments.  Therefore,  this  program  would  be  used 
in  setting  up  the  experiment,  not  in  collecting  the  actual  data. 

A  third  program  allows  the  collection  of  500  data  points  at  sampling  time 
intervals  of  multiples  of  100  microseconds.  Once  the  data  have  been  stored  in 
the  Timex/Sinclair ,  the  communications  portion  of  the  program,  together  with  a 
receive/send  program  in  the  Apple,  can  transfer  the  500  data  points  to  the 
Apple  in  one  half  of  one  second.  The  transfer  rate  is  20,000  bits  per  second. 
The  connection  to  the  Apple  is  through  the  paddle  port.  Consequently,  the 
transfer  of  data  can  be  made  to  an 
Apple  II,  and  Apple  1I+,  and  an  Apple 
He  with  no  hardware  modification. 

Once  the  data  have  been  transferred 
to  the  Apple,  a  high  resolution 
graphics  program  can  be  run  to  plot 
the  data.  Figure  3  shows  the  display 
which  was  obtained  after  a  10  second 
collection  period  (500  data  points) 
for  a  swinging  pendulum. 

A  fourth  program  has  been 
written  which  allows  the 
Timex/Sinclair  to  receive  data  from 
the  Apple,  again  at  20,000  baud.  In 
the  planning  stage  is  software  which 
will  load  programs  from  the  Apple 
into  the  Timex/ Sinclair .  With  this 
capability,  a  cassette  tape  recorder  will  not  be  needed  at  each  station.  When 
all  is  completed,  the  system  with  up  to  16  lab  stations  networked  to  the 
Apple,  will  be  controlled  by  the  Apple.  Each  Timex/Sinclair  will  have  the 
capability  to  request  programs  from  the  Apple.  The  programs  will  include 
those  for  specific  experiments  (e.g.,  the  swinging  pendulum)  and  general-use 
programs . 

Since  the  software  is  still  in  the  development  stage,  I  would  appreciate 
suggestions  concerning  types  of  programs  you  would  find  useful  in  your  labs 
(or  any  other  environments  you  envision  for  the  low  cost  networking  system). 

I  left  TERC  to  return  to  Hiram  College  at  the  end  of  March.  However,  I  am 
continuing  work  on  the  project.  I  hope  that  general  user-friendly  software 
can  become  a  reality  by  the  end  of  the  summer.  Anyone  interested  in  making 
suggestions  or  receiving  additional  details  of  the  project  may  call  (216) 
569-5248  or  write:  Larry  Becker,  Department  of  Physics,  P.0.  Box  1778,  Hiram 
College,  Hiram,  OH  44234. 


DID  YOU  KNOW  OR  CARE? 

The  first  two  characters  appearing  together  in  the  ZX-81  and  TS-1000  ROM 
are  Z  and  X.  These  happen  to  be  the  first  two  characters  of  the  keyboard 
decode  table  which  starts  at  location  126. 


SINCLAIR  STUDY  GROUP 


As  you  may  be  aware,  there  are  a  large  number  of  Sinclair-Timex  user 
groups  around  the  U.S.  and  Canada.  We  have  tried  to  get  in  contact  with  them 
by  sending  them  our  newsletter.  Many  have  reciprocated.  Recently,  we  asked 
if  we  could  reprint  some  of  their  material.  The  overall  response  was  "great." 

This  month  we  spotlight  the  Sinclair  Study  Group,  16  Lewis  Street,  New 
Haven,  CT  06513.  The  group  produces  a  terrific  monthly  newsletter,  yearly 
subscriptions  to  which  are  only  $6.  SUE  MAHONEY  IS  COMING!!  This  was  the 
banner  headline  of  the  March  issue.  Below  is  Sue's  report  of  her  visit. 
Opposite  are  three  edited  (for  space)  excerpts  from  the  SSG  newsletter. 

A  Children's  User  Group  by  Sue  Mahoney 

The  New  Haven  Sinclair  Study  Group  is  a  unique  user  group  in  that  the 
member's  ages  range  from  8  to  14  years  old.  Chris  Baldwin,  the  adult  leader, 
founded  the  group  last  year.  Chris  is  a  teacher  in  one  of  the  alternative 
schools  in  Hew  Haven.  The  study  group,  although  it  has  females,  is 
predominately  male.  It  is  a  very  enthusiast  and  energetic  group.  Each  member 
has  a  project  -  some  quite  elaborate.  One  of  the  group's  first  projects  was 
to  build  the  Sinclair  ZX-81  kit.  The  youngest  participant  was  only  seven. 

On  my  recent  visit  I  demonstrated  the  T/S  2000.  The  group's  response  was 
overwhelming  enthusium  and  excitement.  They  were  literally  glued  to  the  edges 
of  their  seats.  They  asked  many,  many  questions.  I  look  forward  to  meeting 
with  them  again.  Chris  indicated  that  anyone  interested  in  starting  a 
children's  group  or  becoming  a  children's  group  sponsor  should  contact  him. 


ITS  HERE!! 

The  keyboard  you  have 
been  waiting  for! 


A  LARGE  60  KEY  TACTILE  FEEL  KEYBOARD 
(MEASURES  10"  x  4")  THAT  PLUGS  INTO  THE  SAME 
CONNECTORS  AS  EXISTING  KEYBOARD  ON  YOUR 
ZX81  OR  TIMEX  SINCLAIR  1000.  IT  HAS  ALL 
SILKSCREENED  LEGENDS  IN  3  COLORS  ON  THE 
BASE;  MOLDED  LEGENDS  &  GRAPHICS  ON  KEY  TOPS; 
8  AUTOMATIC  SHIFT  KEYS  (NO  SHIFTING  REQUIRED) 
FOR  EDIT,  DELETE,  SINGLE  &  DOUBLE  QUOTES. 
COLON.  SEMI-COLON,  FUNCTION  &  STOP;  5"  SPACE 
BAR;  2  SHIFT  KEYS;  NUMERIC  KEY  PAD. 


ONLY  $84.95 


MASS.  RESIDENTS  ADD  5%  SALES  TAX 
SHIPPING  &  HANDLING  $4.00/UNIT 

QUANTITY  DISCOUNTS.  WE 
WILL  ACCEPT  MC/VISA.  PLEASE  INCLUDE  #’S,  EXP. 
DATE  AND  SIGNATURE.  FOR  MORE  INFORMATION 
SEND  SASE.  SEND  INQUIRIES,  CHECK  OR  MONEY 
ORDER  TO:  J^ry 

SUITE  75 

711  SOUTHERN  ARTERY 
_ QUINCY, MA  02169 


Dear  Fellow  Computerists, 

I  offer  Timex  software  for  people  who  want 
to  learn  as  well  as  just  use.  Every  product 
comes  complete  with  instructions,  program 
listing,  and  a  thorough  enlightening  text  of 
how  the  program  works. 

My  programs  are  top  quality  too.  In  fact, 
my  ZX  Data  Finder  program  was  reviewed 
in  SYNC.  Here's  what  they  said: 


"ZX  DATA  FINDER  is  the  best  most 
economical  data  handling  program  yet." 

SYNC  Magazine  1/83 


They  don't  give  reviews  like  that  for  junk. 
Write  for  my  free  catalog.  It  has  programs 
for  both  BASIC  and  M.C.  programmers. 

Plus:  PROWRITER  PRINTERS  for  $399.95!! 
Make  your  Volkswagen  drive  a  Cadillac! 


Thomas  B.  Woods 
P.O.  Box  64,  Jefferson,  NH  03583 
Phone:  (603)  586-7734 


Chicken? 


This  1  K  game  attempts  to  answer  the  age  old  question,  "why  did  the 
chicken  cross  the  road?"  Guide  the  chicken  (C)  across  the  road  to  its  home 
(H)  using  the  8-key.  You'll  soon  discover  there  are  many  vehicles  (V)  on  the 
road  and  there  is  no  turning  back. 

How  does  the  Sinclair  know  when  the  chicken  is  hit  or  gets  home?  Line  25 
directs  the  computer  to  be  ready  to  print  the  chicken  at  its  new  location. 

But  before  the  chicken  is  printed  in  line  45,  the  computer  "looks"  to  see  what 
is  already  on  the  screen  at  the  location.  Line  30  PEEKs  at  addresses  16398 
and  16399  to  find  the  address  of  the  next  PRINT  position  of  the  display  file. 
Line  35  then  PEEKs  there  to  see  if  a  V  (character  59)  is  displayed.  Line  40 
does  the  same  for  H  (character  45). 


Poem  by  Matthew  Quinlan 

The  ZX81  is  compact  and  easy  to  use. 

It  can  do  anything  but  tie  your  shoes. 
Small  and  easy  to  lose. 

No  zapping  to  give  you  the  blues . 

Take  you  on  paths  yet  unexplored. 

You  can  play  it  at  home  and  not  get  bored 
You  don't  even  need  a  80  column  board. 

Plan  your  diet  and  not  get  fat. 

Like  learning  BASIC  is  where  it  is  at. 
Learning  BASIC  is  really  hip. 

I  mean  gag  me  with  a  microchip! 


Antique  Flag  -  How  Old  Is  It?  by  Kent  Zimmermann 

The  program  contains  13  lines  but  here  is  a  way  you  can  enter  it  by 

typing  in  only  four  lines!  Enter  line  1.  Now  EDIT  line  1:  DELETE  the  line 

number  and  replace  it  with  a  10.  Pretty  tricky  all  right.  EDIT  line  10  this 
time,  DELETE  the  line  number  and  replace  it  with  30.  You've  got  the  idea. 

Enter  and  EDIT  lines  5,  50,  and  60  to  finish  the  program.  RUN  up  the  flag  and 
feel  good  about  being  so  clever. 

1  PRINT  "********XXXXXXXXXXXX" 

5  PRINT  "********" 

10  PRINT-" ******** XXXXXXXXXXXX " 

20  PRINT  "********"  Line  1  contains  8  *'s  and 

30  print-" ******** XXXXXXXXXXXX "  20  graphics  spaces 

40  PRINT  "********"  Line  5  contains  8  *'s 

50  PRINT  "XXXXXXXXXXXXXXXXXXXX"  Line  50  contains  20  graphics 

60  PRINT  spaces 

70  PRINT  "XXXXXXXXXXXXXXXXXXXX" 

80  PRINT 

90  PRINT  "XXXXXXXXXXXXXXXXXXXX" 

100  PRINT 

110  PRINT  "XXXXXXXXXXXXXXXXXXXX" 


5  LET  D=2 
10  LET  C=0 
15  LET  D=D+1 
20  PRINT  AT  0,31; ”H" 

25  PRINT  AT  0,C; 

30  LET  N=PEEK  16398+256*PEEK  16399 
35  IF  PEEK  N=59  THEN  GOTO  90 
40  IF  PEEK  N=45  THEN  GOTO  10 
45  PRINT  "C" 

50  LET  U$=STR$  RND 

55  FOR  1=3  TO  D 

60  LET  L=VAL  U$(I)+1 

65  PRINT  AT  5,L;"V";AT  5,L+10; 

"V” ; AT  5,L+20;"V" 

70  NEXT  I 

75  IF  INKEY$  ="8”  THEN  LET  C=C+1 
80  SCROLL 
85  GOTO  20 

90  PRINT  "SPLAT  ";30*(D-3)+C 


TIMEX  1000 


BUSINESS 


Budjetinc .  $9*95 

Inventory  Control  ...  59.95 
Financial  Analyzer  ..  $9.95 

Bookkeeping .  14.95 

Critical  Path 

Analyzer . 12.95 

GAMES 


Leap  Frog  . $9*95 

Star  Voyage  . $9*95 

Fungaioids . $9*9  5 

Invaders . . $9.95 

Chess  . $9.95 

Snakebite . $9.95 

Packman . $9*95 

UTILITY 

Assembler . $9*95 

Compiler . $9*95 

Graph . $9*95 

Q-Save . cal  I  for  price 

AND  MANY  MORE  EXCITING 
PROGRAMS  I 


CALL  FOR  FREE  CATALOG 

DISCOUNT 
SOFTWARE,  INC. 

320  E.  59th  St.  NY,  NY  10022 
Tel:  (21  2)456-0980 


ROM  BUG  #3 

There  is  an  error  in  the  ROM  program  in  our  computer  which  causes  numbers 
between  0.01  and  0.00001  to  be  LPRINTed  incorrectly.  The  bug  occurs  only  with 
printers  using  the  LPRINT  command,  such  as  the  Timex  and  Sinclair  printers. 
Unlike  the  bugs  we  described  in  the  December  and  January  newsletters,  this  bug 
could  have  a  direct  affect  on  you.  Thanks  goes  to  Gary  Preston,  editor  of  the 
Franklin  County  User  Group  newsletter,  Glade  Hill,  Virginia  for  first  making 
us  aware  of  the  problem.  Gary  says  that  anybody  who  has  purchased  the 
Sinclair  printer  should  know  about  the  bug  because  it  is  mentioned  in  the 
printer  manual.  Dave  Miller  discovered  the  additional  information  required  to 
complete  this  article. 

Numbers,  in  magnitude  (absolute  value)  less  than  one  and  containing  two, 
three,  or  four  zeros  following  the  decimal  point,  are  LPRINTed  incorrectly. 
Below  is  what  we  got  with  the  new  Timex  2040  printer: 


How  will  you  take  your 
SYNTAX/ Syntax  Quarterly? 


The  Combination— 12  issues  SYNTAX,  4 

issues  SQ  $39 

The  Catch-up-SYNTAX  Jan.  82-Dec.  83, 

SQ  Nov.  82-Nov.  83  (5  issues),  1  binder  $77 

The  Works-SYNTAX  Nov.  80-Nov.  83, 

SQ  Nov.  82-Nov.  83  (5  issues),  2  binders  $97 

12  issues  of  SYNTAX  $29 

4  issues  of  SQ,  Syntax  Quarterly  $15 


1  issue  SQ  □  Winter  □  Spring  □  Summer  $  4.95 
1  Magazine  binder  to  hold  your  SYNTAX  or  SQ  $  9 

To  order  or  request  more  info,  call  617/456-3661.  Or 
write  SYNTAX/SQ,  RD  2  Box  457,  Harvard,  MA  01451. 

SYNTAX  /Syntax 
Quarterly  for  Timex 
Sinclair  computer 
users. 


The  first  column  is  the  correct  output;  the  second  is  created  by  LPRINT  B  and 
LPRINT  STR$  B;  the  third  by  LPRINT  AT  0,15;  STR$  B;  the  fourth  by 
LPRINT  .001,  etc.  Numbers  0.01  or  larger  are  printed  correctly.  Numbers 
smaller  than  0.00001  are  printed  correctly,  but  in  scientific  notation.  To 
eliminate  the  problem  replace  the  LPRINT  statement  with  two  statements,  such 
as  LET  B$=STR$  B  and  LPRINT  B$.  Note  that  two  separate  statements  are 
required.  LPRINT  STR$  B  will  not  work  correctly. 


DISCOUNT  ON  NEW  MAGAZINE:  Timex  Sinclair  User  is  a  4-color,  monthly, 
people-oriented  magazine  and  will  hit  the  North  American  market  with  100,000 
issues  in  May.  It  is  a  North  American  version  of  Sinclair  User,  which  has 
been  successful  in  Europe.  The  first  issue  features  an  exclusive  interview 
with  Dan  Ross,  Chief  Operating  Officer  (V.P.)  of  the  Timex  Computer 
Corporation.  Also,  it  contains  an  article,  with  photos,  by  Sue  Mahoney  about 
how  to  start  a  user  group.  It  costs  $2.95  or  $29.95  for  12  issues.  The 
publisher,  J.  Gladstone,  has  offered  a  $5  discount  to  user  groups,  which  we 
are  passing  on  to  members.  Gladstone  requires  a  minimum  order  and  time  is 
limited.  Contact  us  soon  if  you  are  interested.  And,  oh  yes,  your  $24.95 
subscription  also  gets  you  a  free  "$15  value"  arcade  game  cassette. 


EDUCATOR'S  NEWSLETTER:  The  TEC  News  is  a  quarterly  newsletter  to  be  published 
by  the  Timex-Sinclair  Educator's  User  Group  at  Texas  Wesleyan  College  in 
cooperation  with  the  Timex  Computer  Corporation.  It  is  free  to  educators. 

The  first  edition,  which  is  scheduled  to  be  out  in  late  April,  will  feature 
"Computer  Literacy  for  a  School  Faculty  for  $1500.00"  and  an  introduction  to 
BASIC  for  elementary  school  teachers.  Contact:  M.  Mark  Wasicsko,  Associate 
Dean,  School  of  Education,  Texas  Wesleyan  College,  Ft.  Worth,  TX  76105. 


Time  Ware  Bookware 

Explorer's  Guide  to  the  ZX-81  and 

Timex/ Sinclair  1000 

Mike  Lord 

Mastering  Machine  Code  on  Your 

Timex/ Sinclair  1000 

Toni  Baker 

50  1 K/2K  Games  for  the  Timex 

1000  &  ZX-81 

Alastair  Gourlay  et  at 

The  Timex/ Sinclair  Pocket  Book 

Trevor  Toms 

Making  the  Most  of  Your  Timex 

Tim  Hartnell 

49  Explosive  Games  for  the  Timex 

Tim  Hartnell 

RESTON  PUBLISHING  COMPANY 

1 1480  Sunset  Hills  Road 
Reston,  VA  22090 

or  call  our  toll-free  number: 

800-336-0338 

and  ask  for  TimeWare  Marketing 


SERIOUS  PROGRAMMERS 

'MUST-HAVE'  UTILITIES 
For  ZX-81  and  T/S  1000  Computers 

FILE*S  YS  $10 

Read/Write  Cassette  Data  Tape  Files 
(fast,  flexible,  reliable] 

FILE*B  ASIC  $15 

Save/Merge/Erase  BASIC  Segments 
[includes  FILE'SYS  functions) 

FILE*VARS  $5 

Save/Restore  Strings  &  Arrays 
(requires  FILE'SYS  or  FILE-BASIC) 

B  ASIC*OL  A  Y  $10 

Overlay/Copy  BASIC  Segments 
(permits  full  use  of  64K  RAM) 

Simple  user  interlace  via  USR  function 
Well- documented  user  manuals 

Available  on  tape  cassette  in  relocatable  machine  lang. 

SASE  for  info  Check  or  MO  delivers  now 

S'p 

intis  Ware 

6  Turning  Mill  Road 
Lexington,  MA  02173 


FOR  MORE  INFORMATION 


Sue  Mahoney,  Director  of  the  Sinclair-Timex  User  Group 
c/o  The  Boston  Computer  Society  or  call  (203)  573-5816. 

Jack  Hodgson,  Publisher 

P.0.  Box  526,  Cambridge,  MA  02238,  (617)  354-7899 
Cliff  Danielson,  Editor 

14  Davis  Road,  Chelmsford,  MA  01824,  (617)  256-4638. 

John  Kemeny,  Contributing  Editor  &  User  Group  Correspondent 
284  Great  Road,  Apt.  D5,  Acton,  MA  01720. 

Library  Committee:  Beth  Elloitt,  Sean  O'Rahilly,  and  Bob  Sanchez. 


ADVERTISING  INFORMATION 
Computer  Related  Products  and  Services  Only 
Open  Rate:  $40  per  Quarter  Page 
For  Rate  Card  and  Discount  Information  Contact  the  Publisher 


DIRECTIONS  TO  THE  MEETING 

The  Sinclair-Timex  User  Group  meets  in  the  Large  Science  Auditorium  (Room 
8/2/009)  of  the  University  of  Massachussets  of  Boston,  Harbor  Campus.  The 
Harbor  Campus  is  only  3  miles  from  downtown  Boston  and  easily  accessible  by 
public  and  private  transportation.  From  the  north  or  west,  take  the  Southeast 
Expressway  to  Exit  17.  Turn  left  onto  Columbia  Road.  Enter  the  rotary  and 
take  the  first  right  (Morrissey  Boulevard).  Bear  right  on  the  traffic  island, 
following  UMass/Boston  sign.  Turn  left  into  the  Campus.  From  the  south,  take 
Morrissey  Boulevard  northward  to  the  campus.  On  the  MBTA,  take  the  Red  Line 
(Ashmont  Train)  to  Columbia  Station.  Transfer  to  the  free  University 
shuttlebus  in  the  T  parking  lot. 


OOThe  Boston 
OO  Computer  Society 

Three  Center  Plaza 
Boston,  MA  02108 
617-367-8080 


Nonprofit 
U.S.  Postage 
Paid 

Permit  1138 
Boston,  MA 


Circle  Chess  Group 

A..  F.  Station  is 

pob  63 

Des  Flames, 

- 66 


60017