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1^92      HOLIDAY      X  S  S  OE 


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Club  Stuff 
Editorial 

A  Plea  For  Assistance 
Bill  Pedersen  Writes  (2068) 
Epson  9-Pin  Printer  Enhancements 
QLips  (QL) 

IBM / SPECTRUM  Emulator  (part  2) 
IBM/SPECTRUM  Emulator  (part  3) 
QL  Woes 

2068  BASIC  Tutor 

ZX-81  Resources  -  Joystick 

1992  QL  Library 

SINC-LINK  Contents  (Indexes) 

SPECTRUM  Mods  to  US  Standards 

Use  Less  RAM  By  Typing  More  (2068) 

Computer  Classics  Advert 

Rogues  Gallery 

Seasons  Greetings 


TIMEX- SINCLAIR  USERS  CLUB 


NOV  -  DEC  '92  VOL  lO  -  6 


SINC-LINK  IS  A  PUBLICATION  OF 
THE  TORONTO  TIMEX-SINCLAIR  USERS 
CLUB  AND  IS  ISSUED  6  TIMES  A 
YEAR.  CLUB  MEMBERS  RECEIVE  FREE 
COPIES  AS  PART  OF  THE  $20.  00 
ANNUAL  MEMBERSHIP  FEE. 

NEWSLETTERS  ARE  EXCHANGED,  FREE 
OF         CHARGE,  WITH  OTHER 

TIMEX-SINCLAIR  USERS  GROUPS. 

PLEASE  CREDIT  THIS  PUBLICATION 
AND  THE  AUTHOR  IF  YOU  COPY 
MATERIAL. 

THE  TS2068  &  ZX-81  GROUP  MEETS 
ON  THE  FIRST  WEDNESDAY  OF  EACH 
MONTH  AT  14  RICHOME  COURT, 
SCARBOROUGH,    ONT.    7PM  START. 

THE  QL  SIG  WILL  MEET  WEDNESDAY, 
NOVEMBER  18TH  AT  586  ONEIDA 
DRIVE,  BURLINGTON,  ONT.  7PM 
START.    DECEMBER  DATE  TBA. 

SINC-LINK  IS  PRODUCED  ENTIRELY 
ON  SINCLAIR  AND  TIMEX-SINCLAIR 
COMPUTERS. 

SEND  CORRESPONDANCE  TO: 

Attention:  SINC-LINK  EDITOR 
TORONTO  TIMEX-SINCLAIR  USERS 
CLUB,  14         RICHOME  COURT, 

SCARBOROUGH,  ONTARIO, 
CANADA  M1K  2Y1 


EXECUTIVE  OFFICERS 

PRESIDENT 
TREASURER 
SECRETARY 
ACTIVITIES: 
QL  CONTACT: 
NEWSLETTER : 
LIAISON  OFFICER: 
(  Out-of-town  members  ) 


mm  mm  n 


TORONTO  TIHEX-SINCLRIR 
USERS  CLUB 


(Area  Code  416) 
RENE  BRUNEAU   (  531-9749  ) 
BILL  LAWSON  (  444-8772  ) 
GEORGE  CHAMBERS   (  751-7559  ) 
LOUIS  LAFERRIERE  (  820-3725  ) 
HUGH  HOWIE   (   634-4929  ) 
JEFF  TAYLOR  (   244-8583  ) 
GEORGE  CHAMBERS ,   14  RICHOME  COURT, 
SCARBOROUGH.   ONTARIO.  M1K  2Y1 
(  416-751-7559  ) 


TORONTO  TIMEX-SINCLAIR  USERS  CLUB 


Editorial 


Dayton 

Well,  a  few  things  have  happened  since  last  issue.  Pres  Rene  Bruneau's  family 
and  the  Taylor  family  made  our  respective  ways  to  the  Computerfest  in  Dayton, 
Ohio  at  the  end  of  August.  Rene  and  I  decided  that  we  wanted  to  see  what  kind 
of  Timex-Sinclair  exhibits  were  still  being  put  on  these  days,  not  to  mention 
the  fact  that  we  were  both  anxious  to  visit  the  USAF  museum  out  at  Wright- 
Patterson  Air  Field.  We  weren't  disappointed.  By  the  way,  the  Taylor  family  made 
the  trip  from  Toronto  to  Dayton  in  just  7  hours,  moving  at  slightly  faster  than 
the  speed  limit.  So  for  those  of  you  thinking  about  making  the  trip  next  year, 
it's  not  that  far.  A  little  over  400  miles. 

At  the  Fest  we  met  such  notables  as  Don  Lambert  from  ZXir  QLive  Alive  fame, 
Bill  Pedersen  from  WIDJUP,  Frank  and  Carol  Davis  from  Update  Magazine  and  his 
Mechanical  Affinity  partner,  Paul  Holmgren.  We  missed  making  connections  with 
the  SMUG  folks  who  were  there  with  a  table  of  stuff  but  were  never  there  when 
we  visited.  Mechanical  Affinity  had  a  good  selection  of  T/S  bits  at  their  large 
table  and  Update  was  offering  a  lot  of  documentation. 

Later  Saturday  evening  Rene  and  I  met  Bill  and  Frank  and  we  discussed  various 
topics  about  T/S  computing  well  into  the  wee  hours.  Bill  also  demonstrated  some 
of  the  hidden  features  of  the  TS2068  and  explained  why  areas  of  the  ROM  have  been 
masked.  He  also  showed  us  a  few  features  of  his  CAD  program  for  the  2068.  Very 
interesting. 

For  members  looking  for  lots  of  new  Timex-Sinclair  products,  the  trip  might 
be  disappointing.  But  if  you  have  interests  in  other  computers  as  well,  then 
the  trek  down  to  Dayton  may  be  justifiable.  And  the  museum  is  definitely  worth 
visiting.  I  know  I'll  be  back  next  year. 

Club  Meetings 

The  November  club  meeting  will  be  our  last  at  Forest  Hills  Collegiate.  The 
difficulties  in  access  to  the  school,  to  parking  and  to  getting  all  our  gear  to 
the  new  classroom  (up  and  down  several  flights  of  stairs)  have  necessitated  a 
change  in  venue. 

Starting  in  mid-November,  the  QL  SIG  will  be  meeting  at  Hugh  Howie's  home  in 
Burlington  about  every  month  to  6  weeks.  The  TS2068  and  ZX-81  types  will  continue 
to  meet  on  the  first  Wednesday  of  the  month,  but  at  George  Chambers  home  in 
Scarborough.  Both  places  are  easier  to  get  to  than  the  school,  have  adequate 
parking  and  both  have  the  advantage  of  not  having  to  move  equipment  about  for 
demonstrations.  See  the  blurb  on  the  inside  cover  for  times  and  addresses. 

Executive 

All  the  existing  members  have  agreed  to  continue  in  their  respective  capacities 
except  for  Rene  who  will  be  away  on  an  intensive  programmers  course  for  the  next 
few  months.  In  his  absence,  I  will  act  as  interim  Pres  until  he  returns.  We  had 
an  executive  meeting  in  late  October  at  my  place  to  discuss  the  changes  to 
meetings,  course  of  action  and  an  interesting  mailing  experiment.  More  on  that 
next  issue. 

P.S.  Check  out  the  plea  next  page.  Jeff  Dodds  came  to  our  meeting  last  month 
and  asked  for  assistance.  Can  you  help?    That's  all  for  now...  J.T. 


SINC-LINK 


3 


Plea  for  Assistance  for  the  Disabled. 


Apart  from  being  a  member  of  QUANTA,  I'm  also  a  member  of  a  voluntary  organisation 
called  REMAP.     REMAP  stands  for  Rehabilitation  Engineering  Movement  Advisory  Panel, 
and  we  work  with  local  occupational  therapists,  looking  at  the  needs  and  desires  of 
the  disabled  in  the  community  and  advising  on  what  aids  are  available  and/or  suitable. 
Where  nothing  quite  fits  we  try  to  design  something. 

Most  recently  we  have  been  dealing  with  residents  in  a  Home  for  the  Disabled,  several 
of  whom  are  more  or  less  paralysed  from  the  neck  down. 

These  people  have  the  same  needs  as  everyone  else.     They  need  to  eat,  they  like  to 
read,  they  have  itches  to  scratch  and  a  myriad  of  other  things  to  be  done.     Unlike  you 
and  I  though,  these  things  have  to  be  done  for  them.     I  know  there  are  things  to  do 
all  of  the  above,  but  they  are  expensive  and  individual.     You  require  one  item  for 
each  of  the  above  functions,  each  requiring  space  where  space  is  often  at  a  premium. 
I  am  trying  to  design  a  voice-controlled  robot  arm  to  do  all  of  the  above  things  for 
them. 

Back  home  I  can  buy  ZX81  mother  boards  for  about  $30,  and  I  can  build  an  arm  using 
stepper  motors  for  less  than  $100,  so  a  ZX81  controlled  arm  is  well  within  the  bounds 
of  possibility. 

And  now,  the  appeal.     Back  in  the  early  eighties  in  Britain,  a  firm  known  as  William 
Stuart  Systems  Ltd.,  produced  a  black  box  and  some  software  for  use  on  home  computers 
of  the  day.     ZX81,  Spectrum,  Atari,  Amstrad,  Pet,  Philips,  etc.,     The  package  sold  for 
about  $100,  as  "BIG  EARS",  and  provided  a  voice-controlled  cursor  on  screen.  The 
company  has  now  closed  down  and  can't  be  traced. 

So  if  anyone  out  there  has  heard  of  ,!BIG  EARS"  or  its  equivalent  on  this  side  of  the 
water,  if  anyone  has  the  package  languishing  in  attic,  garret  or  dungeon,  PLEASE? 
PLEASE,  PLEASE  get  in  touch  with  me. 

By  the  time  this  is  published  I'll  be  back  home  where  I  can  be  reached  at  the 
following  address :- 


J.  R.  Dodds 
87/53  Pennywell  Gardens 
Edinburgh.  Scotland. 
EH4  4TF 


SINC-LINK 


2068 


9/4/92 

Mr.  Jeff  Taylor,  Editor 
Toronto  TIMEX-SINCLAIR  Users  Club 
335-75  Lemonwood  Dr. 
Islington,  Ontario     M9A  3L4 

Dear  Jeff, 

I  was  happy  to  meet  you  at  Dayton.    You  are  the  only  Toronto  members  I 
can  remember  meeting  except  for  Larry  Crawford,  but  then,  my  memory  is  not 
that  good  anyway,  as  you  might  have  noticed. 

The  (to  scale)  EPSON  Printer  graphic  you  could  not  XEROX  was  a  XEROX, 
and  a  poor  one  at  that.    A  direct  hi-rez  printout  is  enclosed. 

Because  the  graphic  uses  very  narrow  lines,  it  might  seem  that  they  are 
too  light  to  copy.    Unlike  DRAFT  mode,  individual  dots  are  connected.  Good 
XEROX  copies  can  repeat  this  fine  detail  without  darkening,  though  some  can 
improve  general  appearance.  (It  was  printed  using  a  24  pin  printer  and  HP 
graphics  language  from  ASCII  files.) 

I  had  meant  to  do  the  same  for  24  pin  printers,  but  doing  an  honest  job 
requires  six  pages;  and  even  then,  organizing  them  in  a  clear  manner 
requires  quite  a  bit  of  supporting  text. 

In  the  same  vein,  it  is  actually  possible  to  get  360  horizontal  dots 
per  inch  on  an  FX80  using  multiple  passes  and  intermixing  character  and 
graphic  modes.    Explaining  how  this  is  done  in  print  —  forget  it!  It 
involves  printing  blanks  using  PICA,  backspacing  using  ELITE,  and  then  going 
to  a  graphic  mode  for  one  example.    Because  added  resolution  using  six 
passes  does  not  appreciably  improve  CAD,  it  was  not  used. 


With  a  humungous  amount  of  work  I  can  capture  screen  images  which 
happen  to  contain  gray-scale  windows  from  a  multimedia  encyclopaedia. 
Getting  these  onto  a  TIMEX-SINCLAIR  disk  isn't  easy,  nor  would  copying  a  hex 
printout  by  hand.    That  is  why  I'm  looking  forward  to  getting  a  file  from 
you  containing  A2D  encoded  pixel  data  along  with  a  simple  description  of  how 
the  file  is  encoded  and  what  it  portays. 

As  with  CAD,  different  printers  work  best  with  particular  methods  of 
"dithering"  and  gray  levels.    The  same  applies  to  screen  video  modes.  The 
TS2068  is  most  amenable  to  4x4  pixel  "gixels"  giving  17  shades.  That 
requires  a  file  4  bits  "deep",  that  is,  4  bits  per  pixel  usually  packed  two 
pixels  per  byte.    An  uncompressed  TIFF  file  is  often  exactly  this  format. 

TV  pictures  can  be  quantized  in  many  different  ways,  but  what  is  nearly 
universal  is  real-time  sample  intervals  integrated  and  then  converted  to 
digital  form  as  scanning  continues.    These  digitized  samples  are  usually 
blocked  by  scan  line  and  field.    Two  fields  comprise  one  frame.    One  full 
interlace  frame  contains  525  lines,  only  about  400  represent  picture  data. 
The  rest  are  border,  vertical  retrace,  color  burst  and  sync  pulse  templates. 

The  TS2068  has  192  non-interlaced  scan  lines  of  data  out  of  262.  The 
horizontal  scan  frequency  is  exact,  but  the  vertical  is  fast  by  525/524,  not 
enough  to  bother. 

A  single  field  with  256  samples  per  line  would  supply  enough  data  for 
16  screens  of  panned  dithered  display  or  dot  matrix  dump  output.  It  would 
also  fill  a  landscape  oriented  printed  page.  Fewer  samples  per  line  could 
be  used,  but  then  dithering  routines  have  to  integrate  samples  from  two  or 
more  scan  lines  for  each  gixel. 


SINC-LINK 


5 


2068 


For  best  results,  no  fewer  than  128  samples  per  line  should  be  used 
with  no  less  than  four  bit  gray  resolution.    The  absolute  minimum  is  64 
samples  per  scan  line  at  3  bits  per  sample.    Anything  less  yields  strictly 
amateur  results  by  comparison.    More  gives  an  opportunity  to  correct  for 
factors  like  overexposure  and  printer  "gamma".    Gamma  is  a  correction  factor 
which  can  make  the  screen  and  the  printed  page  look  identical  viewed  side  by 
side. 

Round  dots,  whether  from  pin  impacts  or  ink  droplets  have  difficulty  in 
registering  near-black  detail.    Dots  overlap  long  before  they  completely 
cover  the  area.    One  common  partial  cure  is  to  re-define  a  square  array  of 
four  almost  obliterating  dots  as  a  single  pixel  before  creating  gixels.  A 
very  few  printers  actually  have  square  pins. 

When  round  dots  must  be  used,  and  only  17  gray  levels  (nonlinear)  are 
used  per  gixel,  samples  6  to  8  bits  deep  can  be  mapped  using  a  pallet  to 
correct  for  nonlinear ity. 

Other  problems  exist  for  printers  with  different  sizes  of  pins,  pin 
spacing,  and  dot  pitches.    Some  laser  printers  operate  like  they  have  nearly 
square  dots,  too.    A  few  special  tests  can  determine  that. 

In  spite  of  the  complexity  of  visual  presentation,  the  computer  can  do 
near  miracles  when  given  enough  data.    Programmers  should  never  forget  that 
taking  convenience  short-cuts  is  hazardous  to  results.    This  is  especially 
true  when  learning  about  what  is  being  done. 

If  I  can,  I  plan  to  come  out  with  my  own  DOS  some  time  next  year.  This 
development  will  apply  to  all  TS2068s  and  clones  wherever  they  are.  It 
all  hinges  on  getting  my  ROM  BYPASS  to  work  like  the  TIMEX  BEU  without 
having  to  open  the  case  for  modifications. 

In  case  LARKEN  faithful  are  worried,  just  don't  change  a  thing.  Of 
course  they  won't  be  able  to  use  expansion  bus  bankswitching  because  both 
LKDOS  and  JLO  SAFE  wrest  priority  from  the  operating  system.    I  have  not 
yet  found  a  suitable  way  to  negotiate  this  difficulty,  descended  from 
Interface  1.    I  surely  don't  want  to  propagate  that  problem  to  still  another 
tier.    If  others  try  to  merge  the  systems  I  advise  caution  and  realization 
of  the  consequences  of  good  intentions. 

Hangin'  in  there,  baby, 

Bill  Pedersen 


SINC-LINK 


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SINC-LINK 


QL 


Q  L  I  P  S 
by  Hugh  Howie 

CHUCK         QUILL         OUT?   NO       S   I  R  R  E  E 

Each  new  word  processor   to  come  on  the  market    is  extolled  to 
make  the  use  of  Quill   obsolete.     These  statements  are  mere 
ramblings  and  ravings  of   the  producer  of   this  new  "ya  gotta 
have  this"   item  just   to  make  you  rush  out   and  buy  this  new 
and  improved  and  out  of   this  world  word  processor. 

I   am  using  Quill   to  write  this   letter   to-day,    and  I  have  to 
admit   I   can  not  do  as   fancy  a  job  as  with  ray  regular  word 
processor.     But   then  again,    I   cannot  use  my  regular  word 
processor  on  a  plain  jane  128  K  QL  either.     Most  of   the  new 
w/p's  require  quite  a  bit  more  than  128  K  to  operate,  and 
those  that  might  be  able   to  fit    into   the  standard  QL  do  not 
leave  much  if  any,    room  for   the  document. 

Another   little  thing  the  producer  of   the  new  W/P  tells  you, 
is   that   the  new  W/P  retains  many  of   the  Quill  key  press 
functions,   so   there   is  not  all   that  much  to  relearn. 

You  will  also  note  that  those  new  W/P 1 s  do  not  replace  each 
other,  they  are  supposed  to  replace  Quill.  Why  is  everyone 
so  down  on  Quill? 

Compared  to  many  W/P's  Quill   is  very  easy  to  use  and  does  not 
require  a  long   learning  period.     You  can  sit  down  and  write  a 
letter  with  Quill  with  only  a  few  minutes  study,   and  still 
make  an  acceptable   job  of  doing  so. 

It   is  also  the  one  Word  Processor   that   each  and  every  QL  user 
has   in  common.     We  ALL  have  it,    and  we  are  all   capable  of 
writing  with  Quill. 

Every  programmer   uses  Quill   to  write   the   explanation  of  how 
his/her  program  operates.     This   is  because   the  programmer 
KNOWS   that   we  all   have  Quill.     What   a  great   honor   it    is   to  be 
recognised  as  being  so  popular. 

Every  new  W/P  has  the  facility  to  import  Quill  as  a  QUILL_DOC 
file. 

Quill   has   been   in  use   for   about   eight   years,    that's  right, 
count    them!   And   they  are  still    trying   to   replace  it! 

I  must   admit   that   those  new  W/P's  are  really  nice  to  work 
with  once  you   learn  the   intricasies  of   their  use,   but  we 
still  need  our  old  stand-by  Quill,    so  why  not  use  it. 

Write  to  this  Newsletter   to-day,    right   now.     USE  QUILL.  The 
only  Word  Processor   that   is  common  to  ALL  QL  users. 

CHUCK  QUILL  OUT?  NEVER  

Quill    is   still   being  used  by  programmers   for   their  doc  files, 
and   I   am  using  QUILL   to  write  this  article.     Not  bad  for  a 
program  some  are   trying   to  replace,  EH? 


SINC-LINK 


2068 


Ronald  M.  Cavin  II 
1741  Marshlyn  Ct . 
Columbus,  OH  43220  U.S.A. 
614/538-1808 


Dear  George, 

I  hope  some  of  our  readers  found  the  last  article 
interesting!   I've  found  this  venture  fascinating.   I'll  try  to 
keep  going  as  long  as  the  readers  want.   I  believe  this  may 
breathe  some  much  needed  new  life  in  our  little  boxes. 

Enough  preliminaries,  on  with  the  show.  As  I  mentioned 
last  article,  we  now  need  to  transfer  our  copy  of  rom  from  the 
Spectrum  to  the  IBM.   If  you  read  the  issues  of  SINC-LINK  as  I 
suggested,  you're  probably  way  ahead  of  me.  However,   for  those 
who  didn't,   for  whatever  reason,  we'll  briefly  cover  this 
ground . 

What  you  will  need  is  an  appropriate  RS-232  cable,  a  NULL 
MODEM,  and  terminal  software  for  both  computers.  Again,   let  me 
recommend  Rene  Bruneau ' s  work  in  the  NOV-DEC  '91  issue,  and  Bob 
Mitchell's  letter  in  the  MAR-APR  '92  newsletter.  These  two 
readings  will  provide  you  with  much  more  detail  than  we 
intended  to  enter  into  during  this  series.  However,   if  there  is 
enough  demand  for  these  particulars  again,   I'm  willing  to  set 
them  out  on  paper. 

As  I  said  last  time,  my  IBM  has  an  internal  2400  baud 
modem.  Attached  to  the  Timex  is  an  AERCO  version  of  the  Z-SIO 
card.  Thus  my  transfer  rate  is  limited  to  1200  baud!  I  am  using 
MAXCOM,  by  Larry  Kenny,  on  the  Timex,  and  a  program  called 
Telix,  written  by  one  of  your  fellow  Canadians,  on  the  IBM. 

Connect  the  computers,  placing  the  NULL  MODEM  between 
them.  Start  both  terminal  programs,  making  sure  each  machine  is 
set  correctly  in  software,   i.e.  COM  port,  baud  rates,  UART 
setup  (8/1/N) ,  and  XMODEM  protocol.     Be  aware  that  XMODEM  will 
add  128  bytes  to  your  transfers!  Thus,  when  you  look  at  the 
file  size  on  the  PC,   it  will  be  16512  long!  This  phenomenon  is 
not  new!  Normally  this  doesn't  mean  much.  However  the  Spectrum 
emulator  program  JPP-B2.EXE  expects  to  see  a  file  EXACTLY  16384 
bytes  long.  We'll  have  to  do  a  little  editing  on  the  file. 

Start  your  transfer!  Tell  MAXCOM  to  send  (headerless) ,  and 
the  IBM  to  receive  SPECTR.C1.  You  should  observe  some  type  of 
visual  confirmation  that  the  transfer  is  in  process.  On  my 
setup,  MAXCOM  displays  a  (+)  character  for  each  block  sent, 
while  Telix  has  a  large  status  box  which  show  the  bytes 
received,  CRC  errors,  etc.  Once  the  transfer  is  done,  both 
computers  will  indicate  so.  Maxcom  gives  a  screen  message, 
while  Telix  gives  both  visual  and  audible  indicators.  Before 
next  issue,  see  if  you  can  locate  a  Hex  editor  for  your  IBM. 


SINC-LINK 


9 


2068 


Ronald  M.  Cavin  IT 
1741  Marshlyn  Ct . 
Columbus,  OH  43220  U.S.A. 

Dear  George, 

By  now  I  would  expect  that  many  of  you  IBM-TIMEXERS  have 
obtained  a  copy  JPP.EXE.  We  will  fire  it  up  by  the  close  of 
this  article.  So  lets  go! 

We  left  off  last  time  at  the  termination  of  the  rom 
transfer.  Somewhere  on  your  IBM  you  should  have  a  file  called 
SPECTR.C1,  which  is  a  image  of  the  Spectrum  rom.  Also  remember 
that  the  file  will  be  128  bytes  larger  than  we  want,   i.e.  16512 
rather  than  16384.   Since  the  emulator  expects  to  see  an  exact 
image,  we  will  have  to  delete  the  extra  bytes.  Without  doing 
this  the  emulation  program  will  never  work! 

Let's  get  rid  of  this  excess  baggage!   I  suggested  you 
obtain  a  HEX  editor  for  your  clone  to  make  this  easy.   Some  may 
want  to  use  DOS  DEBUG,  but  I  prefer  a  little  program  called 
HEXED IT .   It  is  only  program  I've  found  that  allows  you  to 
easily  delete  and  insert  bytes  in  these  type  files.   (For  those 
who  didn't  know,   I  have  provided  George  Chambers  with  a  copy  of 
ALL  the  files  I  have  mentioned  in  these  articles,  with  the 
exception  of  MAXCOM.   I  don't  think  he  would  have  a  problem 
providing  you  a  copy  if  you  ask  him.) 

Call  up  your  editor,  and  using  the  appropriate  commands, 
GOTO  the  files'  absolute  location  16383.  This  should  be  a  3C  in 
hex  format.  Following  this  byte  should  be  128  bytes  of  2QH, 
caused  by  the  XMODEM  protocol.  DELETE  ALL  THE  BYTES  FROM 
LOCATION  16384  THRU  16512!  This  will  leave  you  with  a  file 
16384  bytes  long.  How  nice!  Save  it  to  disk.  NOW  RENAME  FILE 
FROM  SPECTR.C1  TO  SPECTRUM . ROM .  Create  a  subdirectory,  by  the 
name  of  SINCLAIR,  and  copy  JPP-B2.EXE  and  its  associated  files, 
along  with  the  file  rom  image  into  it. 

Just  a  little  more  work  before  the  moment  of  truth.  There 
should  be  a  file  in  your  SINCLAIR  subdirectory  named  PATH.JPP. 
Use  an  ASCII  text  editor  and  make  the  two  lines  read  like  those 
be  1 ow : 

*.SNA  -    .    ;  C:\SINCLAIR 
*.R0M  -   .    ;  C:\SINCLAIR 
Save  this  file  under  its  original  name  i.e.  PATH.JPP.  Now,  for 
the  moment  you've  been  waiting  for.  Make  sure  you  are  in  the 
SINCLAIR  subdirectory,  type  JPP  and  hit  ENTER.  What  you  should 
have  is  a  message  like  the  one  below: 

JPP  beta,  built  19/03/92  20:39:56  mail  bug  reports  etc  to 
arnt@swix . i  f  i . unit . no 

Using  "c:\sinclair\spectrum.rom"  as  ROM  image 

Press  any  key  to  return  to  emulator 
Hit  the  ENTER  key  and  watch  him  fly! !  the  F12  key  will  return 
you  do  DOS.  We'll  try  to  get  a  program  going  by  next  issue. 


SINC-LINK 


QL 


QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL 

MY  PURPOSE  IN  WRITING  IS  TO  TELL  YOU  ABOUT  THE  PROBLEMS 
'CHALLANGES'  THAT  SEEM  TO  HAUNT  MY  QL.  I  BELIEVE  THAT  LIVING 
ON  THE  18th  PLOOR  OF  22  STORY  BUILDING  HAS  A  LOT  TO  DO  WITH 
IT.  FOR  EXAMPLE.  THIS  ATTEMPT  IS  THE  FOURTH  AND  THE  ONE  THAT 
HAS  PROGRESSED  MOST,  IN  WORDS  TYPED  AND  SAVED.  TWICE  THE 
CURSOR  DISAPPEARED  AND  THE  MACHINE  LOCKED  UP.  THE  THIRD  TIME, 
WHEN  RELOADING  THE  PROGRAM,  I  GOT  A  READ /WRITE  FAILED 
MESSAGE.    I   GAVE  UP  AND  WENT  FOR  SUPPER. 


THE  PHOTO  WAS  TAKEN  IN  JUNE.  I  WAS  WORKING  WHEN,  ALL  AT  ONCE 
THE  MONITOR  BLINKED.  THE  START  SCREEN  APPEARED  FOLLOWED  BY 
THE  WINDOW  OF  LARGE  PRINT,  OR  SHOULD  I  SAY  SUPER  LETTERS  tc 
DIGITS.  THE  SECOND  PHOTO  (NOT  SHOWN)  INDICATED  THAT  THE 
INFORMATION,  IN  THE  WINDOW,  WAS  CONTINUALLY  CHANGING.  I  SHUT 
THE  EQUIPMENT  DOWN  RATHER  THAN  WAIT  TO  THE  END.  LATER,  A 
MONTH  OR  TWO,  AT  LEAST.  THE  SCREEN  DISPLAYED,  WHAT  I  THOUGHT 
WAS  'CODE'  AND  SHORTLY  AFTER  RESETTING  THE  MACHINE.  THE  SAME 
THING  HAPPENED,  EXCEPT  THIS  TIME  IT  ' SCROLLED'  THE  CODE  AND  I 
WONDERED  IF  I  HAD  JUST  SEEN  THE  'ROM*  GO  BY.  I'VE  BEEN  MOVING 
STUFF  AROUND  AND  HAVE  MADE  MANY  SAVES  AS  WELL  AS  TWO 
PRINTINGS  AND  WE'RE  STILL  GOING  STRONG.  DO  YOU  THINK  IT'S  THE 
BUILDING???         CONTINUED  NEXT  PAGE. 


SINC-LINK 


QL 


QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL  QL 

ANOTHER  CHALLENGE  THAT  OCCURS  FROM  TIME  TO  TIME  IS  DOUBLE 
LISTING  IN  THE  DIRECTORY.  THE  SAME  NAME  LISTED  ONE  BELOW  THE 
OTHER.  I  HAVE  BEEN  TOLD  THAT  I  MUST  HAVE  PLACED  AN  EXTRA 
SPACE,  WHEN  SAVING,  THAT  DOES  NOT  SHOW  UP  IN  THE  LISTING.  I 
HAVE  TRIED  TO  PUT  IN  EXTRA  SPACES  BUT  I'M  SURE  THEY  ARE  NOT 
INCLUDED  IN  THE  SAVE.  I  HAVE  COPIED  TO  ANOTHER  DISK.  THEN 
DELETED  THE  NAME  AND  ONE  OF  THE  TWO  REMAINS.  THEN  TRIED  TO 
DELETE  THE  OTHER  AND  AM  ADVISED  PROGRAM  DOES  NOT  EXIST. 
I  HAVE  COPIED  THE  DISK,  TAKEN  DOWN  THE  NUMBER  OF  SECTORS  USED 
DELETED  THE  FILE  TAKEN  THE  NUMBERS  AGAIN  AND  FOUND  THERE  IS 
STILL  SOMETHING  IN  MEMORY  EVEN  THOUGH  A  REQUEST  TO  LOAD  IS 
RESPONDED  TO  WITH  PROGRAM  DOES  NOT  EXIST. 

RECENTLY,  MY  *_2__DRIVE  BEGAN  TO  ACT  UP.  IT  DEMONSTRATED  THIS 
BY  LISTING  APPROX^  T^LISTINGS  WHEN  I  KNEW  THERE  WERE  69 
FILES  ON  THE  DISK.  I  PROVED  IT  BY  PLACING  THE  DISK  IN 
ANOTHER  DRIVE  AND  REQUESTED  A  DIR  AND  GOT  THE  RESULT  I  WAS 
EXSPECTING.  I  LEARNED  FROM  LOUIS  LAFERRIERE  THAT  THE__SL I PES 
FOR  THE  HEAD  PROBABLY  NEED  A  POLISH.  SO.  I  SHUT  THE  SYSTEM 
DOWN,  UNPLUGED  THE  POWER  SUPPLY,  REMOVED  THE  DRIVE  FROM  ITS 
CASE,  REMOVED  TWO  SMALL  GROUPS  of  lead  connectors  and  two 
screws.  This  allows  the  removal  o-f  the  top  board  and  exposes 
the  head  mechanism.  By  wrapping  an  inch  wide  strip  of  (soft) 
cloth  around  the  guide  rod,  working  the  cloth  up  and  down, 
you  remove  any  build  up  of  dust  etc.  The  head  can  be  slid 
back  and  forth  to  allow  you  to  get  at  most  of  the  guide  rods. 
Reassemble  and  test.  My  effort  paid  off  immediately.  One 
might  get  the  idea  that  he  knew  what  he  was  about. 

ON  BOARD  THIS  QL  IS  A  MINERVA  ROM  INSTALLED  BY  GEORGE 
CHAMBERS.  FOR  A  LONG  TIME  AFTER,  WHEN  THE  SCREEN  THAT  TELLS 
WHAT  IS  CONNECTED,  i.e.  CARE  QJUMP  TOOLKIT  VER.  2.09  @  1984 
AND  UNDER  THAT,  CUMANA  DISK  INTERFACE  VER  1.14,  WHICH  was 
REPEATED  THREE  TIMES.  RECENTLY  I  READ  ONE  OF  HOWARD  CLASES' 
ARTICLES  WHERE  HE  EXPLAINED  WITH  MINERVA,  ON  POWER  UP  THE 
CHECKING  SYSTEM  MAY  PASS  BY  THE  PARTICULAR  SPOT  AND  EACH  TIME 
IT  WOULD  REPORT  AND  RECORD.  MY  APOLOGIES  TO  MR.  CLASE  FOR 
THE  TERMINOLOGY  AND  MY  THANKS,  AS  I  OFTEN  WONDERED  WHY  THERE 
WERE   THREE  PRINTINGS.    BY   THE  WAY    IT   DOESN'T   HAPPEN  NOW? 

IT  IS  NOTED  THAT  MY  LAST  'CONTRIBUTION'  TO  THE  NEWS  LETTER 
APPEARED  IN  THE  JUL / AUG  1939  ISSUE.  SO  I  WILL  TAKE  THIS 
OPPORTUNITY  TO  SAY  THANKS  TO  ALL  THE  OTHER  CONTRIBUTING 
MEMBERS,  WHO  HELP  ME  LEARN  MORE  ABOUT  QL  SUPERBASIC  AND  TO 
THE  LOCAL  CLUB  MEMBERS. WHO  MAKE  COMPUTING  POSSIBLE  FOR  ME. 

W  K    (BILL)  LAWSON 


12 


SINC-LINK 


2068 


TS  2068  BASIC  TUTOR 
by  Warren  Fricke 

SCREENS 

SCREENS  is  a  very  useful   function  on  the  TS2068  but   it  has  a  few 
limitations  that  are  well  known.     It  has  two  principal  uses.  One  is  to  SAVE 
a  screen  to  tape.     This  is  explained  on  pages  J 60  and  161,   and  appendix  A 
of  the  manual.     From  these  sources  we  learn  that.... 

SAVE  "PROG"  SCREENS,   really  means 

SAVE   "PROG"  CODE   1638b, 691 2 

The  6912  bytes  of  memory  starting  at  address  1638b  include  the  entire 
display  file  and  all  of  it's  attr  ibutes.     Hence  all  characters,  including 
graphics  and  colour,   are  SAVEd  by  this  procedure.     We  may  use  either  of  the 
above  two  lines  to  do  so. 

SCREENS  has  a  second  use,   and  that   is  to   identify  ind  iv  idual  characters, 
given  their  screen  line,   L,   and  column  number,   C,   as  in.... 

PRINT  SCREENS  (L,C) 

Usea  this  way  SCREENS  is  colour  blind  and  a  bit  myoptic.    It  can  only 
recognise  single  block  characters  whose  code  is  between  32( space)  and 
1 27( copyr ight  symbol).    It  cannot  distinguish  between  inverse  and  normal 
characters,   seeing  them  only  as  normal,  and  it  does  not  see  graphics  at 
all.      These  character  i  st  i  cs  of  SCREENS  can  be  demonstrated  by  the  following 
rout ine: 

___    10  PRINT  "CHAR-  CODE  SCREENS     CODE       LEN  " 

20  PRINT  "ACTER     OF       (L,C)     SCREENS  SCR." 

30  PRINT  "  CHAR.  (L,C)  (L,C)" 

100  FOR  n  -  5  TO  21 
110  INPUT  aS 

120  PRINT  AT  n,1;a$;    TAB  7;   CODE  a$;    TAB  15;   SCREENS  (n,1); 

TAB  22;   CODE  SCREENS  (n,1);    TAB  30;   LEN  SCREENS  ( n,  1  ) 
130  NEXT  n 

This  routine  when  RUN  will  ask  for  the  INPUT  of  a  s  ingle-block  character. 
Any  character  may  be  entered  in  response:  normal,    inverse,   graphic,  etc. 
The  routine  in  turn  will  print  out  a  single  line  of  information  on  such 
character,   all  of  which  concerns  it's  appearance  to  SCREENS* 

The  first  two  columns  confirm  the  character  that  was  INPUT  and  show  it's 
correct  code,    if  it  has  one.    Inverse  characters  have  no  code  and  are 
assigned  inverse  control  code  20.    The  last  three  columns  show  the  way  that 
SCREENS  sees  this  character;  what  character  it  sees,   what  code  it  assigns 
to  the  character,   and   it's  LENgth.     This  knowledge  enables  us  to  use  the 
function  correct  1 y. 

FIGURE  1   is  a  screen  dump  of  the  results  from  a  number  of  characters 
entered.     The  first  character  was  a  solid  square  made  by  using  graphics 
mode  and  the  shifted  8-key.     The  second  character  was  a  solid  square  made 
using   mversed  video  with  the  space  bar.     The  third  character  was  made  in 
graphics  mode  using  the  8-key.    The  fourth  was  a  space  from  the  space  bar 

lone.  Note  that  SCREENS  by  the  results  in  the  last  three  columns,   sees  no 
difference.   In  all  cases  SCREENS  sees  these  characters  as  thouoh  all  were 
made  by  the  space  bar  alone. 


SINC-LINK 


2068 


Next  there  are  some  mixed  normal  and  inverse  characters.   To  SCREENS, 
inverse  and  normal  are  both  seen  as  normal.   SCREENS  cannot  tell  the 
difference  between  them. 

Then  lump  all  kinds  of  graphics  together.   SCREENS  does  not  see  them  at 
all,   because  it  reports  them  as  having  zero  code  and  zero  LEN,   and  empty 
string.     Go  back  to  the  solid  blocks  at  the  beginning  of  the  dump.  SCREENS 
saw  them  all  as  spaces  as   it  gave  them  a  LEN  of  one.  Nothing  at  all  and 
space  are  two  different  things,   so  SCREENS  differentiates  to  this  extent. 

SCREENS  and  PRINT  POSITION 

SCREENS  is  used  in  many  game  programs  to  detect  the  presence  of  a 
particular  character  in  the  PRINT  POSITION.     This  is  the  block  on  the  32  x 
2U-  grid  of  the  screen  where  the  very  next  character  will  be  printed.  One  of 
the  system  variables  keeps  track  of  this  for  the  computer  because  the 
position  constant  1 y  changes  as  the  program  runs. 

To  demonstrate  PRINT  POSITION  we  will  start  with  a  simple  common  program 
that  does  nothing  more  than  move  a  player's  piece,   or  puck,   around  the 
screen  by  touching  one  of  tne  four  arrow  keys.   We  will  call  the  program 
FOUR-DIRECTION  MOVEMENT. . . 

10  LET  1=10:  LET  c=15 
30  LET  11=1:   LET  cc=c 

40  LET  !=!+( INKEY$="6"  AND  L<21 )-( I NKEYS="7 "  AND  L>0) 
50  LET  C=C+( INKEY$="8"  AND  C<31  )-(  INKEY$=»5"  AND  C>0 ) 
60  PRINT  AT  L,C; 
80  PRINT  "*" 

90  PRINT  AT  LL9CC;"   "  AND  ( LL<>L  OR  CC<>C):   PAUSE  0 
100  GO  TO  30 

Note  that  lines  60  and  80  usually  appear  as  a  single- line  reading: 
PRINT  AT  L,C;"*" 

We  have  split  it   into  the  two  separate  instructions,   where  to  print  and 
what  to  print.    The  reason  will  soon  be  clear.    Try  it  out  as  shown. 

We  are  now  ready  to  include  some  targets,   a  single  character  in  this 
case,  des  ignated  by  bS.   The  following  add  it ional   lines  will  generate  up  to 
35  such  random  targets,   d  istr  ibuted  randomly  over  the  screen. 

2     INPUT  b$ 

4     FOR     n  =   1    TO  35 

6     PRINT  at  21*RND,   31*RND;  bS 

8     NEXT  n 

Now  we  can  RUN  the  program  again  and  when  asked  for  b$,   enter  the  letter 
"o"  or  "X"  for  the  time  being.     Move  the  puck  about  and  it  will  wipe  out 
the  targets  as  it  passes  over  them. 

In  a  game  program  some  add  it  ional  action   is  usually  taken  when  the  puck 
hits  a  target.     So  we'll  add  another  line  asking  SCREENS  to   look  at  the 
PRINT  POSITION  contained   in  LINE  60  and  to  take  some  special  action  if  a 
target  happens  to  be  there  before  the  puck  is  printed  over  the  spot. 
Again,    for  the  sake  of  s  impl ic  ity,   the  action  will  be  just  a  BEEP. 

70     IF  SCREENS  (L,C)  =  BS     THEN  BEEP  .05,25 


14 


SINC-LINK 


2068 


We  can  also  use  SCREENS  in  a  negative  sense  by  rewr it  ing  I ine  70  to 
read: 

70     IF  SCREENS  (L,C)  <>    ""  THEN  BEEP  .05,25 

Now  RUN  the  program  and  enter  any  character  with  the  CODE  of  33  to  127. 
Enter  the  character,   not  the  CODE  number.     Move  the  puck  about  and  we 
should  get  a  BEEP  each  time  a  character  is  hit.     Try  running  the  program 
and  entering  inverse  characters  or  some  graphic  ones.   They  do  not  work,  and 
now  you  know  why. 

Now  we  can  use  anything  at  all  for  a  target  as  the  field  has  only  targets 
and  spaces.   There  is  only  one  drawback.  SCREENS  does  not  know  the  identity 
of  the  targets.     It  only  knows  that  they  are  not  spaces.     In  some  game 
arrangements  this  is  all  that  needs  to  be  known. 

Have  you  figured  out  the  reason  for  the  PAUSE  0  in  line  90?  Without  it 
the  GOTO  construct  ion  fills  up  the  PRINT  POSITION  in  line  60  with  the  puck 
itself.     SCREENS  reads  the  wrong  character  and  BEEPs.   With  PAUSE  the 
program  is  held  up  until  an  arrow  key  is  touched.     In  this  way  SCREENS 
looks  at  the  print  position  just  before  the  puck  gets  to  print  on  it.  This 
is  the  essence  of  this  kind  of  a  game  program. 

Line  70  is  usually  written   in  terms  of  CODE  SCREENS  (L,C).    To  be 
cons istant  with  this  practice,   the  code  number  of  the  target  character 
should  be  used  after  the  =  mark  instead  of  it's  string  counterpart .  Either 
method  works. 

As  we  have  seen,   SCREENS   is   limited   in   it's  capab i I  it ies.   But  the  TS2068 
has  at  least  four  other  methods  of  character   identification  that  can  be 
used  in  these  s  ituat  ions.   Some  of  these  are  not  commonly  known  but  will  be 
d  iscussed  in  coming  issues  of  QuarTerS. 


This  article  was  re-typed  from  one  appear  ing   in  the  Summer  1985  issue  of 
the  QuarTerS  publ  i  cat  i  on.    It  is  the  first  of  a  series  of  articles  by  Warren 
Fricke  that  we  shall  be  re-publishing.   G.  Chambers 


SINC-LINK 


15 


ZX8 1      RESOURCES     —  JOYSTICK 

Rene  Bruneau    Noveaber  1992 


Several  aeetings  ago,  Jeff  Taylor  deaoed  a  Zebra  joystick 
interface  for  the  2X81.  At  that  tiie,  several  people 
expressed  an  interest  in  taking  one,  so  I  looked  through  ay 
files  for  a  circuit  that  I  could  use  in  a  construction 
article.  I  found  one  written  up  in  the  June  1984  issue  of 
Electronics  Today  International  and  changed  one  of  the  chips 
and  added  the  edge  connector  to  lount  the  interface  on  the 
back  of  the  ZX81.  The  interface  is  1/Q  sapped  to  Port  31, 
■aking  it  compatible  with  the  2068  to  play  Spectrua  and  2068 
prograis  that  use  a  Keapston  Joystick  systei.  It  will  also 
work  with  a  Coaaodore  1351  louse  in  joystick  lode. 

THE  HARDWARE 

As  with  past  projects.  I  have  provided  a  PCB  aask  to  be 
photocopied  onto  TEC  200  lylar  fill  for  transferring  to  a 
blank  board.  Load  the  coiponents  as  shown  on  the  overlay, 
being  careful  to  install  the  sockets  and  capacitor 
correctly.  The  edge  connector  is  located  on  the  copper  side 
of  the  board,  with  the  coiponents  and  extender  on  the  side 
facing  away  from  the  coiputer.  Check  for  poor  solder  joints 
and  juips  between  traces  and  clean  any  that  are  suspect. 
Before  you  install  the  ICs  on  the  board,  plug  the  assembly 
onto  the  rear  edge  connector  of  your  coaputer,  turn  it  on, 
and  confiri  that  the  coiputer  initializes  properly.  If  it 
doesn't,  quickly  shut  off  the  aachine  and  check  your  work 
again. 

TESTING 

If  you  have  access  to  a  2068,  testing  is  siiple.  Enter  the 
following  prograi  and  run  it  with  a  joystick  plugged  in. 

1  PRINT  AT  15,10;  IN  31 

2  PAUSE  5 

3  PRINT  AT  15,10;'  1 

4  6QT0  1 

For   the  ZX81,  a  short  aachine  code  prograi  Bust  be  entered 
as  follows: 

1  REM  123456 

2  FOR  X=16514  TO  16519 

3  INPUT  A 

4  POKE  X,A 

5  NEXT  X 

6  CLS 

7  PRINT  AT  15,10;  USR  16514 

8  PRINT  AT  15,10;"  ' 

9  60TO  7 

The  data  requested  in  line  3  is: 
219,  31,  6,  0,  79,  201 

If  the  interface  is  working  correctly,  a  0  will  be  printed 
in  the  Middle  of  the  screen.  The  nuiber  should  change  as  you 
aove  the  joystick  or  press  the  fire  button.  The  nuaber 
printed  will  correspond  with  those  shown  below.  Note  that 
holding  the  stick  in  the  corners  will  give  you  a  sum  of  the 
vertical  and  horizontal  values.  For  exaaple,  with  the  stick 
in  the  top  right  corner  a  9  is  printed  on  the  screen, 
holding  down  the  fire  button  at  the  saae  tiae  increases  the 
nuiber  by  15  (DOWN  +  RIGHT  +  FIRE  =  3  +  1  +  16  =  25) 


Write  code  to  12  REM  stateient 


ACTION 

Right 

Left 

Up 

Down 
Fire 


RESULT  PRINTED 

1 
2 
4 
8 
16 


BIT 

0 

1 

■-. 

3 
4 


For  those  who  have  a  copy  of  FIGHT  SIMULATOR,  here  are  some 
pokes  to  adapt  it  to  allow  the  use  of  a  joystick.  Use  a 
FOR/NEXT  loop  to  enter  the  code.  He  will  provide  additional 
prograa  pokes  in  future  issues  of  this  newsletter. 


ADD. 

19447 


CODE 

219,  31 
254,  0 
40,  32 
254,  4 

32,  4 

33,  239,  239 
201 

254,  8 

32,  4 

33,  239,  223 
201 

254,  2 

32,  4 

33,  247,  223 
201 

254,  1 

32,  4 

33,  239,  247 
201 

205,  187,  2 
201 


LABEL 


DOWN 


LEFT 


RIGHT 


EXIT 


with  50  Xs. 
MNEMONIC 

IN  A,  31 

CP  0 

JR  Z,  EXIT 
CP  4 

JRNZ,  DOWN 

LD  HL,  239,  239 

RET 

CP  8 

JRNZ,  LEFT 

LD  HL,  223,  239 

RET 

CP  2 

JRNZ,  RIGHT 
LD  HL,  223,  247 
RET 
CP  1 

JRNZ,  EXIT 

LD  HL,  247,  239 

RET 

CALL  KSCAN 

RET 


COMPONENT  LIST 

Ul  74LS02 
112  74LS30 
U3  74LS640 

CI      4u7  Tantalua  Capacitor 

R1-R5  IK  1/4  watt  Resistor 

PI      Male  9-pin  Subd  Socket 

P2      ZX81  Edge  connector  and  extender 

Misc.  2-14  pin  dip,  1-20  pin  dip,  Solid  wire  for  juapers 

CIRCUIT  DIAGRAM 


0vD7D6D5D«D3O2OJ  D0 
/oN  A  A  gj  sl  J  ?1  d 


U3 


IORQ  6 


*  ii — \w 
<i — vw- 

,1  \w- 

l  W\r 

(i — m- 


0y 


COMPONENT  PLACEMENT 


ADD.       DEC.  CODE 

17316      205,  247,  75 


MNEMONIC 

Call  19447 


ST"'  *  ■ 


is  w 


SINC-LINK 


ZX-81 


1992  QL  Library 

New  and  revised 


There  are  at  present  271  programs/utilities  in  the  QL  Library,  in  the  following 
categories . 

Disk  Title        Free  Mem   Contents    


o 

Catalogue 

1  OA  0/1  AAD 

f-\  tr  i        r\  ri 

r.i  hrarv  Ca1"a  1  osue 

o 

Comm_l 

DDD  /  X'+H-U 

Cornrmim  rations 

o 

Demo_l 

A.77  /1  LLC) 

Dpitio 

iy  emu  kj 

o 

Game  1 

QQ  /1  LLC) 

77/ if tU 

Xv  c  Via  et-i 

(ranip  ^ 

VJ  CtlUC  o 

o 

Game_2 

llUx/  X4-H-U 

New 

vjctuitr  o 

o 

brar  I 

1 1  in/1/iAfi 

11XU/  1441/ 

Kcv  X o cvJ. 

('It*  a  oVl  1  P  <? 

o 

HJC_1 

DJ7/  XH-H-U 

New 

Hr>ufar*H    T      CI^^P  file 

o 

Math_l 

993/1440 

Maths 

o 

Pic  s  1 

->9A  /  1  LLC) 

IN  fcrW 

P  1  P1"11T%P  CI 

JL  -L       l_  Ul  c  o 

o 

Psion_l 

1041/1440 

Revised 

Psion  related  subjects 

o 

Sound_l 

1269/1440 

New 

Sound  and  music 

o 

Spec_l 

1050/1440 

Revised 

Founts.  Tests.  _doc  info  files. 

o 

Spec_2 

15/1440 

Manusoft  file 

o 

Spec_3 

870/1440 

Revised 

Small. C.  by  Tim  Swenson 

o 

Tute_l 

1260/1440 

New 

Tutorials 

o 

Util_l 

24/1440 

Revised 

Utilities 

o 

Z88 

3/1440 

Z88  files  in  QL  format (Untested) 

o 

TK2_manual 

834/1440 

New 

TK2_Manual 

o 

QHJ_1 

814/1440 

New 

QL  Hackers  Journal  by  Tim  Swenson 

(For  advanced  QL  Programmesrs)  Vols  1-9 

This  is  a  total  of  19  disks  of  varying  interest.     Some  old,  some  changed,  some 
new. 

I  know  that  some  of  those  disks  could  be  lumped  together,  but  I  feel  that  this 
presentation  leaves  possibilities  for  additions  without  too  much  trouble. 

If  you  wish  to  order  any  of  the  above,  please  send  FORMATTED  disks  of  your 
choice,  with  return  postage. 

I  can  copy  to  5  1/4  40  or  80  track  or  to  3  1/2  DD  or  HD.     Complete  disks  only. 

For  the  MDV  user  I  will  try  to  copy  to  your  formatted  Cartridge  if  you  designate 
the  particular  program  by  Disk  Title  and  Title  of  program. 

It  is  almost  impossible  to  fit  more  than  one  program  onto  one  cartridge. 

I  will  not  be  responsible  for  faulty  cartridges  or  disks,  or  for  the  formatting 
of  such. 

Hugh  H.  Howie. 
QL  Librarian 
586  Oneida  Dr 
Burlington.  0NT. 
L7T  3V3 
(416)  634-4929 


18     %  |?  hm 


SINC-LINK 


S INC- LINK  CONTENTS 


prepared  by  George  Chambers 

Each  entry  is  prefixed  with  the  year  and  first  month  of  issue  (eg,  8301  = 
Jan/Feb  1983,   8303  =  Mar/Apr  1983);  and  with  the  volume    &  number  (eg,  3/1 
=  volume  3  number  1 ).       These  are  usually    followed  by  the  (  first  )  page 
number  of  the  entry. 

1983 

8301  1/1  P. 01   Is  your  calendar  accurate  by  George  Chambers. 

8301  1/1  P. 02  Cassette  Recorder  Interface  by  George  Chambers.   Tips  on 
cooling  your  ZX81  by  Peter  Harvey. 

8301  1/1  P. 03  The  ZX81  as  a  Character  Generator  by  J.J  Cast  i llos.  Adding 
a  Joystick  to  the  ZX81  by  Stan  P  iotrowsk  i . 

8301  1/1  P. 05  Review  of  Memotech  High  Resolut  ion  Graphics  Pack  by  J.J, 
Cast  i I los.     In  Praise  of  ZX  Printers  by  Greg  Lloyd. 

8302  1/2  P. 02  Review  of  Mult i FORTH  EPROM  Chip  for  the  ZX81  by  J.J. 
Cast i I los. 

8302  1/2  P.  03  Book  Review  "Master  ing  your  Timex  Sinclair  1000  Personal 
Computer  by  J.J.  Cast  i I los.  A  Short  program  in  FORTH  by  J.J.  Cast  i I los. 
8302  1/2  P. 04  BUGBYTE  ZXTK  Appl  icat  ion  notes  by  George  Chambers. 
8302  1/2  P. 05  Tape  Head  alignment  by  Stan  P  iotrowsk  i . 

8302  1/2  P.  06  Understand  ing  ans  using  PEEK  and  POKE  by  Stan  P iotrowsk /• 

8302  1/2  P. 10  Adding  2K  RAM  internally  to  the  ZX81  by  Jack  Paget. 

8303  1/3  P.  01  Mult  i pi icat  ion  accuracy  with  the  ZX81  by  George  Chambers. 
8303  1/3  P. 02  Advanced  Machine  Code  programming  by  Stan  P iotrowsk  i . 
8303  1/3  P.  06  A  modem  for  the  TIMEX  1000  or  ZX81  by  Franz  Hrazdira. 
8303  1/3  P. 05  Tips  on  protect  ing  your  ZX81  program  from  pirates  by  J.J 

Cast i llos. 

8303  1/3  P. 06  Reviews  of  Hunter  boards,  Memotech' s  Memocalc,  MCODER,  and 

the  program  EVOLUTION  by  J.J.  Cast i llos. 

************************* 

7  964 

6401  2/1  P. 01  Messages  from  the  Preident  and  Editor 

8401  2/1  P. 02  Poor  mans  FASTLOAD  by  C.   Goudeseune.   BASIC  PROGRAMMING,  a 
lengthy  article  by  C.  Goudeseune. 

8401  2/1  P. 09  Lengthy  article  on  Machine  Code  programming  by  Stan 
P iotrowsk i . 

8402  2/2  P. 01  Meeting  agenda 

8402  2/2  P.  02  Making  a  joystick  for  the  ZX81 .    Including  the  hardware  A 
software  by  George  Chambers. 
8402  2/2  P.  05  Basic  programming  by  Stan  P iotrowsk i( ?) . 
8402  2/2  P. 07  Machine  Code  programming  by  Stan  P iotrowsk  i . 
8402  2/2  P. 12  Several  computer  puzzles  by  George  Chambers 

8402  2/2  P. 14  TTSUC  membership  survey. 

8403  2/3  P. 01  Hardware  hints  (cooling  the  ZX81 )  by  Virgil  Roman. 
8403  2/3  P. 02  Aligning  decimal  points  on  the  ZX81  by  George  Chambers 
8403  2/3  P.  06  Merging  Basic  programs  by  George  Chambers.  Machine  Code 

programming  article  by  Stan  P  iotrowsk  i( ? ) 

8403  2/3  P.  09  Article  on  adding  single-key  shifted  functions  to  your 
external  keyboard  using  diodes. 


SINC-LINK 


19 


8404  2/4  P. 01  Checking  computer  accuracy  by  Bill  White, 
8404  2/4  P. 02  Machine  Code  program  with  one  POP  by  K.   Van  Vie  it, 
8404  2/4  P. 03  Machine  code  programming  by  Stan  P iotrowsk i . 
8404  2/4  P.  08  BASIC  programming  article  by  Stan  P  iotrowsk  i . 

8404  21 4  P. 10  Low  Memory  -  SAVE I  LOAD  program  by  Bob  Croker 

8405  2/5  P. 01  BASIC  programming  article  by  Stan  P iotrowsk i. 

8405  21 5  P. 04  Machine  Code  programming  article  by  Stan  P iotrowsk i . 
8405  2/5  P.  08  A  short  program  in  FORTH  ( ZX81  )  by  J.J.  Castillos 
8405  2/5  P. 09  An  article  on  the  Z80  reg  isters  and  instruct  ions. 

8405  2/5  P.  10  Z80  OPCODES  table. 

8406  2/6  P. 01  Letter  from  the  Editor 

8406  2/6  P. 02  Store  BASIC  on  an  EPROM  with  an  EPROM  programmer  by  Virgil 
Roman. 

8406  2/6  P. 04  SYNCBITS  -  a  list  of  resources  for  all  T/S  computers  by  Ian 
Robertson. 

8406  2/6  P. 05  Article  on  building  an  8K  EEPROM  board  by  John  Roach. 
8406  2/6  P. 07  Ideas  on  includ  ing  author  credits  in  a  Basic  program  by 
George  Chambers 

8406  2/6  P. 09  TS  2068  programming  suggest  ions  by  John  Roach. 
8406  2/6  P.  10  Machine  Code  programming  by  John  Roach. 
8406  2/6  P. 11   Table  of  ZX81  Key  (board)  values 
8406  2/6  P. 12  Schematic  for  8K  EEPROM  board  by  John  Roach. 

*************************** 

10/3  p. 3     Sine-Link   Contents  R.Mitchell 
10/3  p. 6     Notes  from  my  correspondence  G. Chambers 
10/3  p. 9     QLIPS  Beginners  Corner  A.Pywell    (H. Howie-1 
10/3  p. 15  ZX81  Resources  64  K  memory  R.Bruneau 
10/3  p. 17  German  QL  Users  Club  B.Harmer 
10/3  p. 18  QL  Success  CP/M  Emulator  L . Laf err lere 
10/3  p. 22  Britain's  Spectrum  Scene  G.Parrish 
10/3  p. 24  4Times  screen*  Abed  Kahale 
10/3  p. 25  ZX81  Resourves  Rem  Generator  R.Bruneau 
10/3  p. 27  ZX81  Magazine  A.Baune 
10/3  p. 31   A  tape   index  L.Cottrell 
10/3  p. 32  Clone  vs  2068  S.Gunnhouse 
10/3  p. 35  Challenge  to  programmers  D.Lambert 
10/3  p. 36  Analog  Science  K . L . Thompspon 
10/3  p. 36  YMLTK  L.Laferriere 
10/3  p. 37  QLIPS  Winde:;  H.Howie 
10/3  p. 38  ZX81   Tight  Security  A. Ho 

10/3  p. 39  Disk  Drive  power  supply  LARKEN  H.Miller 
10/4  p. 5     Sine-Link  Contents  R.Mitchell 
10/4  p. 11  Superbasic  Your  Powerful   Friend  A.Pywell 
10/4  p. 15   ZX81   Resources  Moving  Ramtop  R.Bruneau 
10/4  p. 15  ZX81  Sound  Analysis 

10/4  p. 16   IBM  Clone  and  Spectrum   .  R.Calvin 
10/4  p. 17  TEXT87plus4  H.Howie 
10/4  p. 19  2068  Second  Screen  D. Fritz 

10/4  p. 21  QL  Ramblings  Joystick , TEXT87p lus4  ,  maillist.L. Laf err i ere 
10/4  p. 22  Mike's  Notebook  M.Di  Rienzo 

10/4  p. 23  ZX81   Newsletter  for  Sinclair/Time):  A.Baune 
10/4  p. 27  Reduce  number  of   disks  with  TK2 .  H.Howie 
10/4  p.2S  QLIPS  etc.  H.Howie 

10/5   p. 3  Editorial    (    Interesting   ?    )  J.Taylor 
10/5  p. 3  Spectrum  Game  "   Aliens  "   7  J.Taylor 
10/5  p. 4  Programming  exercise  2068  G.Chambers 
10/5  p. 7  Using  ALTKEY  for   "   Macros   "in  QUILL  H.J.Ciase 
10/5   p. 11   ZX81   Resources  R.Bruneau 

10/5  p. 13  Larken  format   to  match   IBM   ?  S.Gunnhouse 
10/5  p. 17  Visit   to  NESQLUG  H.Howie 
10/5  p. 18  TREE_BAS  H.Howie 

10/5   p. 19  Disks , cassettes ,    modems,    etc.  B.Harmer 
10/5   p. 20  Battery  Operated  Bike  D.Clery 
10/5  p. 21  ZX81 

10/5   p. 25  Transferring  files   from   Z-B8  to  2068  J.Shepard 
10/5  p. 27  Superdasic  Ramblings  A.Pywell 
10/5  p. 30  QLIPS,   Ribbons.  H.Howie 
10/5   p. 31   2068  on  business   trips  L.Cottrell 
10/5  p. 32  Larken  Oliger  system.  G.Chambers 
10/5  p . 33  Emulators  C.Delhez 

10/5  p. 35  Emulators   ?  386  to  Spectrum.   R. Calvin 
10/5  p. 37  SINC-LINK  Contents  R.Mitchell 


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SINC-LINK  listings  9207 
issues  10-3  to  10-5  ^07 
by  L.  Laferriere  9;07 

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SINC-LINK 


SPECTRUM 


ZX  SPECTRUM  MODIFICATIONS  TO  U.S.A.  STANDARDS 


While  I  was  on  a  business  trip  to  Europe  fast  December,   I  purchased  a 
ZX  Spectrum  computer.   No,    I'm  not  tired  of  my  TS2068,   but  my  first  love  is 
my  so  I der ing  iron  and  a  heap  of  el ectron  ic  components  with  a  burning 
desire  to  experiment  with  these  el ectron  ic  marvels  we  call  computers. 

The  TS2068  and  the  ZX  Spectrum  are  closely  related  in  design,  however 
there  are  physical  and  e I ectron  ic  differences  between  both  computers.  Many 
European  publ  icat  ions  provide  a  store  of  add-on  do- it-yourse I f  hardware 
articles  to  enhance  the  Spectrum,   but  NOT  The  TS2068.  My  Spectrum  will  now 
become  a  test  bed  for  building  Spectrum  hardware,   then  mod  if y  ing  the 
hardware  to  operate  with  the  TS2068. 

This  article  is  ded  icated  to  those  individuals  who  have  a  Spectrum  or 
intend  to  purchase  one  and  want  to  get  the  most  out  of  it  -  to  operate  on 
110  volts  without  a  step-up  transformer;  convert  the  PAL  decoder  to 
operate  on  NTSC  video  standard  for  colour  operat ion;  and  add  a  compos  it e 
video  output  for  your  monitor. 


The  orinal  Spectrum  power  supply  module  requires  220  VAC  at  the 
primary,   and  outputs  approximately  9-10  VDC.      Two  options  for  the 
mod  i  f  i cat  i on  can  be  cons  idered . 

1  -  Rewind  the  original  transformer  primary  winding  to  operate  at  110V AC, 
or  adding  add  it  ional  windings  to  the  secondary  to  up  the  output  voltage, 
using  the  original  primary  windings.   The  transformer  design  allows  fairly 
easy  rewind  ing  of  the  primary  or  secondary,   but   it   is  work, 

2  -  Remove  the  original  transformer  and  replace  it  with  a  commercial  110 
VAC,  18  VAC  Centre  Tap  transformer. 

I  chose  option  two  because  I  had  an  18  VAC  CT  transformer  on  hand  that 
fit   into  the  Spectrum  power  supply  case.    The  reason  a  18  VAC  CT 
transformer  was  selected,    is  that  a  9-10  volt  transformer  is  pretty  hard 
to  come  by,   and  by  cutting  the  transformer  centre  tap  and  paralleling  both 
9  volt  windings  with  proper  phasing,    the  voltage  is  9  volts  with  the 
operat  ing  current  doubled.     Also  the  original  power  supply  rect  if  icat  ion 
and  filter  assembly  can  still  be  used  without  mod  i f  i cat  i on. 


POWER  SUPPLY  CONVERSION 


Modul a  tor 


18  Vol  t  Trans-former  Secondar  y  Leads 
Exposed  After  Opening  Insulation  Tape 


SINC-LINK 


21 


SPtCIRUM 

The  first  step  in  this  operation  is  to  remove  the  power  supply  case  top 
by  removing  three  (3)  Philips  head  screws.  Remove  the  case  top  and  set 
aside  with  the  three  retaining  screws  previously  removed.  Carefully  remove 
the  transformer  with  the  filter  assembly  and  both  input  and  output  cables. 
Measure  the  transformer  core  (metal   laminat  ions )  for  height,   width,  and 
length  and  record  these  measurements.   I  used  an  old  Radio  Shack 
transformer,   however  I'm  not  sure  it  is  still  available.  A  visit  to  any 
el ectronics  TV  supply  house  will  provide  you  with  the  necessary 
tranformer.  Ask  for  an  18  Volt  Centre  Tap,    1  amp  filament  Transformer,  and 
measure  it  so  that  what  you  buy  will  fit  the  case.  Surgery  on  the 
transformer  first  begins  with  removal  of  the  mounting  frame.  Set  the 
transformer  on  your  work  bench  upside  down  and  pry  up  the  four  (4) 
retaining  tabs  on  the  bottom  of  your  transformer  core.   With  a  common 
screwdriver  (flat  blade),    insert  the  blade  between  the  mounting  frame  and 
the  transformer  core  and  apply  a  prying  motion  until  the  frame  has  exposed 
both  sides  of  the  transformer  core.  Remove  the  frame  from  the  core  ana 
trial  fit  the  tranformer  into  the  power  supply  case.   If  the  f,t   is  a 
little  loose,   a  strip  of  foam  tape  (weather  stripping)  will  snug  things  up 
at  assemDiy  rime. 

Remove  the  transformer  from  the  case  and  locate  the  secondary  side. 
This  is  the  side  with  either  two  green  lugs  and  one  lead  with  stripes,  or 
three  solder  lugs.   With  a  sharp  knife  (X-ACTO,   #11  blade)  or  razor  blade, 
using  light  cutting  pressure,   cut  a  slit  from  top  to  bottom  at  the  centre 
point  on  the  transformer  secondary  side  insul at  ion.  Carefully  pull  both 
sides  of  the  cut  tape  towards  their  respect  ive  sides  which  should  expose 
three  copper  wires  either  terminated  to  lugs  or  wires. 

Using  the  low  wattage  soldering  iron,  desolder  the  centre  tap  winding 
from  a  lug  or  wire.  Examine  the  copper  wire  tap;   it  can  be  either  a  loop, 
or  two  separate  wires.    If  it  is  a  loop,  cut  the  loop,  and  if  it  is  two 
wires,   separate  them.   Cut  two  small  strips  of  tape,   any  kind,   and  place 
one  strip  on  one  of  the  centre  tap  wires.   This  is  for  identification 
purposes  only,   to  properly  phase  both  both  secondary  windings  which  we 
will  parallel.   Using  an  ohmmeter  or  a  cont inuity  tester,   connect  one  lead 
of  the  test   instrument  to  the  CT  lead  having  the  strip  of  tape.     The  other 
test  lead  is  touched  to  either  or  both  lugs/wires  to  locate  the  mating 
lead  of  the  CT  winding  having  the  tape.     Now,   follow  this  careful  I y.  Place 
the  other  strip  of  tape  on  the  lug/lead  which  did  NOT  indicate  continuity. 
Connect  both  taped  wire  ends  together,   remove  both  strips  of  tape  and 
solder  these  leads  together.  Connect  the  remaining  two  leads  together  and 
solder  these  as  you  had  soldered  the  others. 

Before  going  further,   the  transformer  output  voltage  must  be  tested  for 
a  voltage  and  correct  phasing.  Connect  a  two  wire  cable  with  a  proper  110 
VAC  connector  to  the  transformer  primary.    The  primary  side  should  state 
110  VAC  or  have  two  black  wires  attached  to  it.    Insulate  these  connect  ions 
to  avoid  any  contact  with  the  line  voltage.   Set  your  voltmeter  function 
switch  to  AC  and  the  range  switch  to  25-50  VAC.   Plug  the  line  cord   into  an 
AC  wall  outlet  and  touch  both  secondary  connect  ions  with  the  voltmeter 
test  probes.    If  the  voltmeter  is  reading  9  VAC  or  higher  then  all    is  well. 
On  the  other  hand,    if  no  voltage  is  present,    then  remove  the  line  cord 
from  the  wall  socket,   desolder  the  secondary  connect  ions  previously  made 
and  switch  secondary  leads.  Repeat  all  previous  steps  until  proper  AC 
voltage  os  obtained. 

Attach  two  2"  leads  to  the  secondary  contacts  and  solder,   then  place 
some  insul at ing  tape  over  the  exposed  secondary  leads.  Place  the 
transformer  into  the  bottom  of  the  case  and  add  some  foam-backed  tape  to 
it   if  the  fit   is  too  loose. 


SINC-LINK 


SPECTRUM 

Desolder  the  filter  assembly  circuit  board  from  the  original 
transformer  and  place  in  the  case  next  to  the  transformer  secondary. 
Connect  both  secondary  wires  to  the  filter  circuit  board  in  the  holes 
which  the  original  transformer  was  soldered  to.  Any  wire  can  connect  to 
either  hole  for  tranformer  connection.    If  you  wish,   the  AC  line  strain 
relief  from  the  original   transformer  can  be  removed  and  the  110  VAC  line 
cord  can  be  inserted  into  it  for  a  custom  fit. 

Set  the  function  switch  on  your  voltmeter  to  DC  and  the  range  switch  to 
25  VDC.  Plug  the   line  cord  into  the  AC  socket  and  monitor  the  output 
voltage  at  the  power  supply  connector.  A  reading  of  9  VDC  or  greater  will 
be  present. 

NTSC  COLOUR  OUTPUT 

The  Spectrum  operates  on  a  European  video  standard  called  PAL,  which 
means  Phase  Alternating  Lines.  PAL  provides  625  TV  lines  as  opposed  to  525 
TV  lines  with  NTSC.    The  colour  is  automat ical I y  corrected  at  trasnm iss ion, 
thus  eliminating  the  requirement  for  a  Tint  or  Hue  control.     If  we  operate 
the  Spectrum  without  a  change   in  colour  burst  frequency,   then  the  output 
on  a  TV  screen  will  be  black  and  white,   and  possibly  some  diagonal  lines. 
Fortunate  I y  a  crystal  change  from  U.U3  MHz  to  3.57  MHz   is  all   that  is 
necessary  to  have  the  Spectrum  perform  in  colour  in  the  USA. 

A  trip  to  your  local  Radio  Shack  should  solve  the  crystal  requirement. 
Ask  for  part  No.   272-1310,   COLORBURST  CRYSTAL  at  $1.69.    If  they  do  not 
have  the  crystal,   any  TV  or  E tectonic  Supply  outlet  will  have  one.  Just 
make  sure  it   is  a  miniature  case,  HU-18. 

Please  note  there  are  two  (2)  crystals   in  the  Spectrum  computer.  A  14 
MHz  crystal  operates  the  system  clock  and  should  not  be  removed  or 
replaced  with  a  crystal  of  another  frequency.    The  PAL  crystal,   4.43  MHz  is 
the  one  to  replace. 

Open  the  Spectrum  case  by  removing  five  (5)  Philips  screws  on  the  case 
bottom.  Carefully  open  the  keyboard  section  of  the  case  and  locate  a 
Philips  screw  approximately  centre  on  the  PC  board.  Remove  this  screw  and 
lift  out  the  PC  assembly  with  the  keyboard  still  attached.   If  you  are 
careful,   you  will  not  have  to  remove  the  keyboard  case  section. 

The  4.43  MHz  crystal    is  located  next  to  the  TV  RF  modul ator .  Ensure 
that  you  have  located  the  right  crystal  as  the  clock  crystal  shares  the 
same  approximate  location.   Heat  up  your  soldering   iron  and  grasp  the  4. 43 
MHz  crystal  with  two  fingers.   D  isconnect  the  solder  ing   iron  from  the  AC 
line,   and  quickly  heat  up  one  crystal   lead  and  gently  pull  with  a  slight 
twist  at  the  crystal.  Repeat  the  previous  step  until  the  crystal  is 
removed.  Note:   the  solder  ing   iron  will  not  zap  any  semiconductor  within 
the  crystal  circuit  with  a  static  charge,    if  disconnected  from  the  AC. 
Plug  the  solder  ing  iron  back  into  the  AC  line  to  build  up  heat.    Insert  the 
3.57  MHz  crystal    into  the  PC  board  using  the  same  holes  as  the  crystal  you 
prev  ious I y  removed.  Again,   d  isconnect  the  solder  ing  iron,   and  quickly 
solder  both  crystal   leads  to  the  PC  board.  Clip  oof  both  leads  of  the 
crystal  on  the  unders  ide  of  the  board.   Place  the  PC  assembly  with  the 
keyboard  into  the  lower  case. 

Attach  a  cable  to  the  modul ator  jack  and  the  other  end  to  the  UHV  leads 
on  a  TV  set.    The  approximate  channel  should  be  between  30  and  36.   Plug  in 
the  modified  power  supply  and  turn  on  your  TV.  Rotate  your  Channel  Select 
switch  until  the  Sinclair  copyright  message  appears  on  your  TV.    If  you  do 
not  wish  to  add  a  Video  Monitor  output  to  your  Spectrum  at  this  time,  then 
d  isconnect  power  and  the  TV  cable,   and  reassemb I e  the  computer  case. 

NOTE:  My  Spectrum  did  not  have  a  trimmer  capac it  or   in  the  crystal 
circuit.   If  yours  does  and  the  image  on  the  TV  screen  appears  poor,  then 
you  may  want  to  attempt  to  adjust  the  trimmer  to  peak  the  picture. 

This  article  appeared  in  an  old  issue  of  the  L.I.S.T.  newsletter,  and 
has  no  credit  line.   I  suspect   it  may  have  been  written  by  Nazir  Pashtoon. 
I  have  retyped  it,   since  my  copy  is  in  poor  cond  it  ion.     G.  Chambers 

SINC-LINK 


from  Nite  Time  News  by  CATUG 


ARTICL 


USE   LESS   RAM  BY   TYPING  MORE 

by 

Bob  Swoger 

Don  Lambert  wrote  me  a  letter  and 
stated  that  being  a  less 
experienced  programmer  he  could 
not  understand  why  I  used 
statements  with  VAL  and  CODE  in 
them. 

The  answer,  Don,  is  to  save 
program  space.  Just  a  couple  of 
bytes  saved  can  sometimes  save  a 
whole  disk  track  of  5090  bytes! 

One  of  my  favorite  examples  is 
Larry  Kenny  opening  up  channel  4 
to  access  his  LKDOS  because  PRINT 

#  4  is  easier  to  type   [less  key 
strokes]    than    RAND    USR  100". 
[page  11  of  his  V3  manual]  Also, 

$J  r^>  he  told  me  it  takes  up  less  RAM 
space  in  a  program.  Well,  LARRY, 
it  can  USE  UP  MORE  RAM  space!  The 
problem  I  have  is  channel  4  is 
also  assigned  to  my  ZEBRA  Talker 
and  I  can't  change  that. 

Consider  a  short  program  to  load 
LogiCall.  Get  in  front  of  your 
machine  and  do  the  following: 

Turn  on  your  TS2068  and  type 
PRINT  FREE  <ENTER>  .  You  get 
38652.  This  is  our  free  RAM 
space.  Now  enter  the  two  lines: 

10  RANDOMIZE  USE  100:   OPEN  #4, 
"dd" 

20  PRINT  #4:   LOAD  "L.B1" 

Now  type  PRINT  FREE  <ENTER>  .  You 
get  38600.  Strange,  29  keystrokes 
used  up  52  bytes! 

Now  EDIT  the  lines  and  put  VAL 
with  quotes  around  the  100  and 
the  4s.  The  program  now  reads: 

10  RANDOMIZE  USE  VAL"100":  OPEN 

#  VAL" 4",  "dd" 

20  PRINT  #  VAL"4":   LOAD  "L.B1" 

Now  type  PRINT  FREE  <ENTER>  .  You 
get  38609.  Strange,  you  just 
added  9  keystrokes  to  the  program 
and  gained  9  bytes  of  RAM! 

Now  lets  try  the  ultimate  RAM 
saving  trick.  Most  numbers  over 
31    can    be    expressed    in  the 


program  as  CODE.  Let's  change 
VAL"100"  to  CODE"d"  ,  do  you 
follow  me,  Don?  It  is  on  page  242 
in  the  TS2068  manual.  The  program 
now  reads: 

10  RANDOMIZE  USE  CODE"d" :  OPEN  # 
VAL" 4",  "dd" 
20  PRINT  #  VAL"4":  LOAD  "L.B1" 

Now  type  PRINT  FREE  <ENTER>  .  You 
get  38611.  Losing  the  two  zeros 
bought  us  two  bytes.  Notice  that 
the  following  statements  all  mean 
the  same  thing. 

RANDOMIZE  USR  100 
RANDOMIZE  USR  VAL  "100" 
RANDOMIZE  USR  CODE  "d" 

But  what  about  OPENing  channel  4 
to  save  RAM  space.  Type  in  the 
program: 


10  LET  h=CODE  "d" 

20  RANDOMIZE  USR  h:  LOAD  "L.B1" 


Now  type  PRINT  FREE  <ENTER>  .  You 
get  38624. 

Both  programs  will  LOAD  LogiCall 
but  the  channel  4  call  uses  41 
bytes  while  the  USR  call  uses 
only  28.  Also,  for  the  record, 
RAND  USR  h  is  six  bytes  shorter 
than  PRINT  #  4  and  just  as  easy 
to  type, 

SO   WHY   OPEN   CHANNEL  4? 


THE  FAR  SIDE  By  GARY  LARSON 


10  bO  ©  1992  FtrWorta  Inc/DmntKrtW  Ov  Unmu  Pro  SynttcMi     J^m— * 


24 


'Well,  this  isn't  very  promising. 

SINC-LINK 


COMPUTER  CLASSICS 

RT  1,    BOX  117 
CABOOL,   MO  -65689 

Repair  Charges  for  SINCLAIR/TIMEX  Computers     Revised  July  1,  1992 

Prices  do  not  include  shipping  and  handling  charges. 

Shioping  charges  will  vary  depending  upon  weight,   distance,   and  method. 
I  will  ship  via  the  cheapest  method  unless  you  specify  otherwise. 
The  minimum  handling  charge  for  shipping  is  $2.00- 

There  may  also  be  an  extra  charge  for  repairing  modified  equipment. 
The  minimum  extra  charge  for  modified  equipment  repair  is  $5.00. 

Definition  of  modified  equipment:     Any  circuitry  changes  on  the  inside  of 
the  equipment  case  that  involved  the  addition  of  components,  wires, 
integrated  circuits,   or  hardware.   Customers  who  send  in  computer  equipment 
that  has  had  modifications  done  to  it,   which  change  the  manufacturer's 

original  design  are  subject  to  paying  extra. 

The  following  items  Mill  be  repaired  for  $5.00  each  +  parts  &  shipping: 

TS-1000       ZX-S1       1016  Ram  Pack       Any  MEMOTECH  Module       ZEBRA  TALKER 

MIRACLE  Centronics 

The  following  items  will  be  repaired  for  $10.00  each  ±  parts  &  shipping: 

TS-1500       TS-2020       TS-2050       PC-8300       ZX-80       Any  BYTE-BACK  Module 
TS-2040  ZX-99       Any  BASICARE  Module 

LARKEN  RAMDISK  Z-SIQ      AERCO  2068  Centronics 

The  following  items  will  be  repaired  for  $1 5.00  each  +  parts  &  shipping: 

TS-2068       SPECTRUM       A&J  MICRODRIVE       LARKEN  2068  FDI       KEMPSTON  FDI 

MIRACLE  512K  LARKEN   1000   FDI        CUMANA  FDI 

CST  FDI 

The  following  items  will  be  repaired  for  $20.00  each  ±  parts  &  shipping: 

ROTRONICS  WAFADRIVE 


The  following  items  will  be  repaired  for  $25.00  each  +  parts  &  shipping: 

SINCLAIR  QL  AERCO  1000  Centronics  AERCO  2068  FDI 
TRUMP  CARD  ZEBRA  2068   FDD  System       AERCO   1000  FDI 

For  repairing  modules,  printers,  monitors,  or  other  computerized  equipment 
not  listed  above  -  write  for  a  price  quote  for  the  items  you  want  repaired 
For  modifying  or  upgrading  any  computer  or  module  -  write  for  a  quote. 

I  also  service  ATARI.   COLECO.   COMMODORE.    IBM ,   OSBORNE.   TI .   and  TRS-80. 

In  house  turn  around  is  usually  2  to  4  weeks. 
Upgrades  and  problem  cases  may   take  longer. 

You  will  be  notified  of  any  unusual  delays  or  excessive  repair  costs. 

(over ) 


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1.  For  repairs,   please  use  a  separate  sheet  of  paper  to  describe  in  detail 
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intermittent.   List  any  software  or  hardware  that  are  associated  with  the 
problem.  Also  list  any  modifications  that  have  been  done  to  your  equipment 

2.  For  upgrades,    please  enclose  or  specify  the  magazine  article  or  other 
source  of  information  for  doing  each  upgrade. 

3.  You  may  include  a  check  or  money  order  as  a  deposit  for  repair  costs. 
You  will  be  notified  if  a  balance  is  due.   Over  amounts  will  be  refunded. 
4  ..     Carefully  pack  and  ship  your  equipment  to  the  address  below  via  UPS 
or  parcel  post.   UPS  is  sometimes  cheaper,  especially  with  heavy  items. 


COMPUTER  CLASSICS 

RT  1,    BOX  117 
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and  their  accessories 


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ROGUES  GALLERY 


Would  you  buy  a  used  Timex-Sinclair  computer  from  these  men? 

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SEASONS 


GREETINGS 


ft  ltd  ImsM rolir  Itoi  tflui) 
'mi  it  tii  take  %i  opportnnitp  to  M)  all  ir 
iubtoiteriS  anil  dotitrilrafert 

i! 

I  top  Jfcto  tear 


SINC-LINK 


Nov/Dec  1992 

November  22,  1992 

Dear  Out-of-Town  Members, 

nu.iTVlnvJ'l*6''6*!1"9  ne"jle*ter,   '  see.  Jeff  says, ' t  here '  s  only  28  pages  this  month'. 
ONLY.   ONLY?  Seems  to  me  that's  quite  enough,   especially  when  I  look  at  the  contents. 

Actually,   we  can  only  send  out  36  pages  before  we  have  to  pay  more  for  postage;  we 
exceed  the  100  grams  marker,   whereupon  we  have  to  pay  $1.30.   To  the  USA,   and  other  foriegn 
countries,   that  ts.  So  it  behooves  us  to  stay  within  that  limit. 


because  we  do 
suffic ient 
appear  in  our 


We  don  t  publish  much  about  our  club  meetings  in  the  newsletter.  Probably 
not  have  a  member  to  take  on  that  task.  Maybe  also,  our  meetings  are  not  of 
interest.  But  this  month  we  have  some  items  to  mention  to  you.   They  should  a 
next  news  letter . 

nn»  illViYnt0Ur Jnll°Wll  "*mb.er.shiP  is  filing  we  have  revised  one  of  our  club  bylaws,  the 
one  pertaining  to  the  definition  of  a  meeting  quorum.  We  were  afraid  we  might  not  be  able 
to  function,  some  time  in  the  future  without  this  change. 

off%%\™us7ndesl°.read  "**  '°  percent  of  tne  membership  must  be  present  to  conduct 

^s;/^;^?:^^" consist  of  a  minimum  or  rive  members' three  °r  *hom  te 

The  change  was  approved  by  a  membership  vote,   with  a  meeting  quorum  of  11  members. 

,nJie:+alS°rhaVt  Z*dJ>ZoblemSt  wit,n  our  Pres*n*  meeting  place,  Forest  Hill  Collegiate 
^SSlViS/Mr  ttr00^'  Difficult/  'J!  Peking,   hard-to-find  meeting  rows,  missing 
^fhroom  facilities,   etc.  So  we  are  going  to  meet  at  my  home  from  now  on,    1U  Richome 
Court.     "ell     we  also  do  have  a  QL  interest  group  who  are  going  to  meet  at  Hugh  Howie's 
home,   on  a  different  Wednesday  of  each  month.  9 

What  this  means  is  that  our  group  has  shrunk  in  size  to  the  point  where  it  is  feasible 
to  meet  in  someone's  home.  But  still  strong  in  enthusiasm.  feasible 

with  S^Stir^^riC^^J^'r^/^'r!^"/^*  a  year  ago  1  suPPl''ea  a  Toronto  museum 
JJ^Su        ,/        f   .y  father  had  knitted  while  he  was  a  prisoner-of-war  durina  the  1st 
World  war.   It  was  knitted  with  needles  made  from  fence  wire,  and  with  wool  unravel 1 ed  from 

ineit°PST°he  ZTlZT*  ^7  *°CkS-   If  *-aS-  °,  S°rt  0f  Saa">ler  *  9'eat  variety  of  patterns 

The  show  is  on  now  "Vnd  Y'"*  a,\exhi.bit l°n  °f  textiles  having  a  human  interest  to  them. 
The  show  is  on  now,  and  I  was  interviewed  on  a  CBC  radio  station  in  connection  with  it. 

}^1L0fr0ii.r  °lUb  members>  *en  Gamey,   took  me  to  task  gently,   for  not  respondino  to  his 

i:^r%i,2r^es^/e%2:x  and  1  hope  he  is  !n  th*     °f  -^r^w: 

He  had  a  point  though. 

refind  171"°°  '*  '        "**  *"m  f°        responding  to  your  letters,  drop  a  line  and 

MscriTfiTeT  ThJdnl  nnrZ;r°1tine  thQ.f  WQ.S  P^Pored  by  Bob  Mitchell,  used  to  sort 
Mscript  files     I  had  a  particular  application  for  it.   What  it  was,   was  this- 

oo  as,  for  It.   ,t  a,so  So.'"£'Zl? S 'ulrVr'y  TuL'er.'"*0         ^  ""^  ""^ 


Another  thing.   In  the  July/August  OOT  letter  I  mentioned  that  I  had  several  disks 
designed  to  allow  the  Spectrum  to  be  emulated  on  a  386-PC  machine.  One  of  our  members  hat 


>"x  icy 


made  a  copy  of  the  disks,   so  if  anyone  is  interested  in  trying  them  out,   I  can  loan  you  a 
W       copy.  Another  suite  of  disks  for  the  club  I ibrary! I  Ask  for  Spectrum  Emulator  disks.  You 
will  need  a  386-  or  later  type  PC  machine  to  be  able  to  make  use  of  themTlfaTbls^someone 
can  try  it  out  and  give  us  a  review  article  for  the  newsletter.   Think  of  it;  your  name  in 
our  newsletter! J 

I  prepared  an  index  for  the  early  issues  of  the  S1NC-LINK  to  round  out  the  index 
prepared  by  Bob  Mitchell.   It  is  in  this  issue  of  the  newsletter.   I  am  placing  the  indexes 
for  the  years  1983  to  1992  on  a  disk  for  the  club  Larken  library.  St i 11 another as yet 
un-numbered  disk  for  the  library!  a*  yGX 

2068erLn^aU  ,hQS  ,?P  ?  buffer  circuit  5°  that  I  can  use  a  remote  keyboard  on  my 

TFLZtZP%  i  '+i-WOU,id  likeJ°  USe  the  k°yboord  separated  from  the  2068  by  a  ribbon  cable 
nn+  ZZZZ  5  feet'n  \ength.   To  do  so  we  need  to  have  a  buffer  circuit,  otherwise  it  will 

£^  £W  ^^T^^a  SE'fc  ThTpTr^d 

3Si:  Ve^iyTrZ  ziTs^.     i  W 

resign  as  President  of  the  club,  but  we  declined  to  accept  it!  ottered  to 

I  have  been  corresponding  with  Bill  Pederson,  recently.   You  may  remember  I  mentionr 


.  m  ■»    -----    —  .  .  .    -  ~  ~  ^ .     ^ ,  •  f    i  k^cih  ijr,     '  wiu   ihu  y   i  amain  ut 

that  in  my  last  missive.  He  has  written  a  letter,   which  I  am  going  to  ask  for  parmiss, 
Vr\/JPrL  ,    "!  °Ur  newslettef'   Jt  contains  some  interesting  tips  and  observations  about  the 
ant  pc  *J~nZ f '  Possibly  in  the  next  newsletter.  Bill  also  send  a  set  of  schematics 

™  7L  Z        layoutJ  Pertaining  to  an  external  ROM  and  EXROM  for  the  2068.   Idea  being  tha 
POM  andiFy^ntreXternai  St?.ie         Chips  and  experiment  with  modifying  the  code  in  the 
%^hZ    EXROM'To  y°ur  dart's  desire,  with  no  need  to  burn  EPROMS,  and  all  that  problem 
Sounds  very  interesting.   I  turned  this  info  over  to  Rene  Bruneau.  Hope  Problem, 
he  will  nibble.  Anyone  else  interested? 

olS^C^nV'ltYK  °7X  ZllnrZr     '  *a¥*  inherit°d  mother  batch  of  them,  including 
in     I'll  sTn7lnn'     ,i*+    •*  C0MPUTING>  and  ™me  misc  magazines  that  have  programs  to  type 
Punk    Everlthina    Vi  *        Y°U  interested.  ^Iso  some  books,  and  a  bunch  of  other 

^O^r^^r'^^r/n^rX^r^  AerC°  interfQCe  t0ardS'  A°y°°*  tested  in  a 

I  seem  to  have    run  out  of  conversat  ion. 
Sincerely, 


George  Chambers