+*+*+*+*+*›         YOUR OTHER COMPUTER›          by John Picken  GCACE›           from PSAN April 1990› (Reprinted  with  permission  and with› THANKS   by   the   OL'HACKERS  ATARI› U.G.Inc., Oceanside, NY›› Do you neglect your other computer --›  the  one  at  the end of the printer› cable? Today's low cost,  dot  matrix› printers   contain   at   least   one› microprocessor, a ROM  with  multiple› character  sets,  and  sufficient RAM› for   buffers   and   user   designed› characters. This makes them computers› --  in  fact  it  makes  them  pretty› powerful   text    processors.    The› majority  of  owners, however, rarely› do anything with their printers  that› can't  be  done  as part of some pre-› packaged software.›› A few years ago,  you  couldn't  gain› much  by learning to talk directly to› your   printer   --   you  could  get› commercial or PD software to  exploit› nearly  all  of  its  features.   But› improvements  in  printer  ROM's have› given the latest models  capabilities› that  were unknown when programs such› as "The PrintShop" and even  some  of› the  most  recently   released   word› processors were authored. If you want› to access these features, there's  no› way  around the necessity of learning› how to talk to your printer.›› Talking to  your  printer  is  not  a› terribly complex task. Unfortunately,› however, many printer manuals  appear› to  have  been  written  by  the same› people   who   wrote   the  "manuals"› packaged with the 800XL. While it  is› possible  to  puzzle  through   them,› assuming  you  have some knowledge of› BASIC (MicroSoft variety),  it  isn't› easy.  To make matters worse, I'm not› sure that  the  authors  of  some  of› these  manuals have much knowledge of› BASIC (ANY variety).›› Assuming you want to learn to control› your  printer,  what can you do about› it?› First, read all/anything  you can lay› hands  on  concerning  printers.   My› printer is a Roland but I have picked› up tips from manuals for  both  Apple› and Star printers. The "Epson Printer› User's   Handbook",   published    by› Ballantine  Books  with a cover price› of $9.95 (US)  is  a  good  place  to› start,  but  it's  only  a start: the› Raven (and its Panasonic  equivalent,› the  KX-P1180)  has many features not› mentionned in the book  and  lacks  a› few that are.›› Don't  forget  computer magazines. It› doesn't   imply  disloyalty  to  your› favourite  brand  to  read  magazines› written for other makes of  computer.› Regardless  of  computer  brand,  the› odds  are  that the printers referred› to can be and  are  used  with  Atari› systems.›› There are two other important ways to› learn how to talk  to  your  printer.› The  first  is  to  ask  questions --›  that's what user groups are for! The› other  method,  one  you will have to› use     at     some     point,     is› experimentation.    Flash    up   the› printer, sit down with  your  printer› manual and start trying out ideas.›› Here's a few hints to get you started› or to stimulate more ideas.  All  are› based  on  my experience with various› Roland and Panasonic  printers.  They› should  work on most Epson compatible› units   depending   on   the  printer› features included.›› HINT #1: Read and re-read the  manual› to    ensure   you   know   all   the› implications of each command you wish› to  use:  Some commands cause loss of› the data in the print buffer  (eg.  a› margin  change);  others   effect   a› carriage  return;  some  change  page› formatting settings (tabs, etc.); and› some may even be ignored depending on› previous  commands.  The  only way to› learn to make effective  use  of  the› various  commands  is to try them out› in   different    combinations    and› sequences.›› HINT  #2: None of the sample programs› in the Roland manual work with  8-bit› machines -- even after you change the› string definitions to  Atari  format.› But,  if  you  OPEN  a  channel   and› replace  the  LPRINT's  with PRINT #,› the   samples   work  correctly.  The› lesson here is: learn enough BASIC to› be able to send output to the printer› without use of LPRINT.  Depending  on› the  computer  and  the  BASIC  used,› LPRINT   produces   results   ranging› anywhere from what you  want  to  the› totally unpredictable. From what I've› read,   it   appears   this  is  more› important with  8-bit's  than  it  is› with ST's and up.›› HINT  #3:  Leave  your  printer's DIP› switches   in   the   "as    shipped"› condition  and  leave  the   exterior› switches   in   the   "Standard"   or› "Program" mode -- you get better  and› more    precise    control    through› software.  With 8-bit computers, this› advice also applies to  any  switches› on  the  printer  interface  (another› manual to read -- groan).›› HINT  #4:  If  you're  using  a  word› processor and not getting the results› you   want,   check    the    program› documentation  to ensure it's capable› of doing what you're asking and  that› you're  asking   correctly.   (Proper› commands   and   a   proper   printer› "driver" or "CNF" file.) Then try the› "Print  to  disk" option. This allows› you  to  examine  the  actual  output› going to the printer using  a  sector› editor,  a  screen  dump of the file,› etc. On the 8-bit, a good way to  use› this  technique  is with TextPro: you› "print" to a disk or RAMdisk file and› then  load  the  new  file  back into› TextPro.›› HINT #5: Experimenting can take a lot› of  paper,   especially   if   you're› playing  with  page formatting. Cheap› paper is not  necessarily  a  bargain› here.  Lightweight  paper   is   less› expensive,  but you can normally only› use one side. The extra  few  dollars› spent  on  20  lb. paper are worth it› when   you   consider  that  you  can› usually use both sides,  if  not  for› printing, then at least, as "scratch"› paper. Also, you can save  a  lot  of› paper  (or  a  lot  of  rewinding) by› ending a file with an "Off  Line"  or› "Remote  Deselect" command (19). This› causes   the    printer    to    quit› immediately    --   before   a   word› processor can issue  a  "Form  Feed".› You'll  then  have  to  issue  an "On› Line" (17)  command  or  re-boot  the› printer before its next use.›› GRAPHICS:  Without  getting into "Bit› Image Graphics", it is possible, with› Roland and Panasonic printers, to use› character graphics. The Raven  allows› you  to  switch  between  Italic  and› Graphic character sets on the fly. In› fact, it is possible to use  both  at› once:  you enable the Graphic set and› get your graphics  by  sending  bytes› greater  than 127 while you can still› obtain   italics   using  the  ESC  4› sequence.   With  older  models,  you› might have to set  the  DIP  switches› and  put the printer into "IBM" mode.› This entails writing  a  new  printer› driver  for  your  word processor and› sacrificing the use of  italics,  but› the  graphics can really dress up the› output.›› This is an area where you have to  be› familiar  with   documentation.   For› example, PaperClip will not allow you› to enter inverse (greater  than  127)› bytes,  so   how   do   you   include› graphics?  Simple,  the  printer  has› commands    to    force    the   most› signifigant bit (msb) either high  or› low and another to tell it to receive› all bytes as  sent.  With  PaperClip,› set  one of the four "user definable"› commands   in   the   CNF  to  enable› graphics and set the MSB  high.  From› then  on, all normal bytes will print› as graphics until you  use  a  second› "user  definable"  command to receive› the bytes as sent.›› TEXT PROCESSING:  Ever  dump  a  text› file  to  the printer direct from DOS› or from a terminal  program?  If  you› did,  you  probably  weren't   overly› ecstatic  with  the  output:  margins› only  1/4"  wide, words broken at the› end of lines, etc. If you want better› results,  you  usually end up loading› the file into a  word  processor  and› formatting  it. How would you like to› be able to dump files directly to the› printer and have the results come out› already formatted with word wrap  and› proper margins on all four sides?›› It's  easy  if  your printer includes› commands  for  perforation  skip  and› auto   justification.  The  following› program produces a  short  file  that› can be sent to the printer prior to a› dump. RUN it once and save  the  file› it produces. To use it, set the print› head at the  perforation,  then  COPY› PRINTER.DAT to the printer before you› send it a  text  file.  Your  printer› will output right justified text with› 1" margins all  around  (the  printer› handles  the  pagination),  with word› wrap,   and   in   highly   readable,› proportional  text. The program is in› Atari BASIC, but the DATA  statements› can  be  just as easily used with any› variety of BASIC, 8-bit or ST.›› 10 OPEN #1,8,0,"D1:PRINTER.DAT"› 20 TRAP 60         Just loop 'til› 30 READ BYTE       out of data› 40 PUT #1,BYTE     error occurs› 50 GOTO 30› 60 END› 70 REM ---------------------------› 100 DATA 17,13,13,13,13› 110 DATA 27,64,27,77› 120 DATA 27,108,9,27,81,87› 130 DATA 27,112,1› 140 DATA 27,97,3› 150 DATA 27,67,66› 160 DATA 27,78,12› 170 DATA 27,107,0› 180 DATA 27,120,0›› Here's the explanation for the  bytes› in the DATA lines:› 100  We  start  with  an  "On   Line"› command  (just  in  case)  and   four› carriage  returns  (if the 13's don't› work   with   your  8-bit  interface,› change them to 155's).› 110 Next we issue a "Reset"  just  to› clear  any  previous   settings   and› select  "Elite"  or 12 cpi. (Makes it› easier to calculate the  3/4"  needed› below).› 120  Now,  set left and right margins› at 3/4" each.  With  standard  paper,› this produces actual margins of 1".› 130  We  enable  Proportional   print› (this  overrides  Elite  but  doesn't› change the margins).› 140  Now  we  select  right-justified› output  which  ensures  word wrap and› microspacing. Note that this  command› always produces a carriage return.› 150  Designate  page  length  of   66› lines.  This  is  not done for length› since 66 is the default,  but  it  is› needed  to reset the printer's top of› page indicator. Reset would  also  do› this  but  would  cancel our previous› commands.› 160 Here we enable  a  12  line  (2")› skip  perforation  which produces the› 1" vertical margins.› 170 This command selects one of  four› NLQ  fonts.  The  final  byte in this› line can be 0 (default), 1, 3, or  6.› If your printer only has a single NLQ› font, just omit this line. (The  TRAP› technique  ensures  we  don't have to› count bytes).› 180 The final  command  selects  NLQ.› The last byte can be 0 for "OFF" or 1› to enable it.  Optionally  just  skip› the line.›› It's  easy  to  modify  the  left and› right margins -- just remember  that,› with  standard paper, you always have› 1/4"  on  either  side  to  start  no› matter what you do.  But  what  about› the top and bottom margins? The trick› is to get the print head down to  the› first  line we want to print on. Then› RESET   THE  TOP  OF  PAGE  INDICATOR› BEFORE DESIGNATING A SKIP PERFORATION› VALUE.  The  skip value must be equal› to twice the vertical margins. So for› 2"  margins,  we'd  have  to  add six› carriage returns and designate a skip› perforation  value  of 24 lines (4").› It's easier than it sounds; play with› it.›› CONCLUSION:    Since    I've    begun› experimenting    with   the   various› printer features, I've  found  I  get› better  output  than  I  can with any› word   processor.   The    techniques› outlined    above    can    be   most› effectively used with a program  such› as TextPro which allows you to insert› and edit printer commands directly in› the  text. This means you can't use a› word processor to  "Print"  since  it› would  confuse  the   commands   with› printable  characters;  instead   you› "Save"  to  a file and then "Copy" it› to   the   printer   or  even  "Save"› directly to the printer. I  think  if› you try some of the ideas here you'll› be   pleasantly   surprised   --  the› operative word is "try".››            +*+*+ end +*+*+*›