ftp.barnyard.co.uk/2015.02.ftp.barnyard.co.uk.tar/ftp.barnyard.co.uk/robot-pd/19132.ZIP/19132A.DSK/basic

Text File | 1998-03-02 | 6KB | 128 lines

     Part 1                      BASICly GOOD

     If you want to program,then learn BASIC.What do  you  mean  you  don't
     know how to program??!! Well,you've come to the right place.

     TURNING ON

     When  ever  you  turn  on  your  CPC,you  all  ways   see   the   word
     "BASIC".So,what is it?

     A BIT OF HISTORY

     BASIC (Beginner's All-purpose Symbolic Instruction Code) was  invented
     in the late 60's.In the 80's there was a boom  in  home  computers,and
     all most all of these computers had BASIC built in.

     EASY PEASY BIG-MAC AND CHIPS

     BASIC is very easy to learn.And you  can  program  some  high  quailty
     programs.(just take a look at Rambase3 and PDPlanner)

     TIME FOR WORK

     Today,we will have a look at printing on the  screen.Don't  worry,this
     is very easy.
         Below is the listing.Those letters at the start of each  line  are
     the typechecker codes.All you do is load  up  Typechecker,and  type-in
     the program below.When you have finished type in LIST.This will  list
     the program below.If the codes at the start of the lines on the screen
     match the ones below,then the line has been typed in correctly.If  the
     codes don't match,then the line is wrong! Oh,don't type-in the codes!
     ______________________________________________________________________
     |                                                                    |
     | DABN 10 ' Program1                                                 |
     | GAII 20 ' By Richard Avery                                         |
     | HAOG 30 ' (c)1994 Richard Avery                                    |
     | AALK 40 '                                                          |
     | BAHG 50 CLS                                                        |
     | JAKP 60 INPUT"What is your name";a$                                |
     | BAJG 70 CLS                                                        |
     | EANE 80 PRINT"Hello"                                               |
     | FACG 90 LOCATE 8,1:PRINT a$                                        |
     | LAHG 100 LOCATE 1,2:PRINT"My name is arnold"                       |
     | BAJI 110 END                                                       |
     |____________________________________________________________________|

     Now let's take a look at each line.

     EVERY REM HURTS

                                  10 ' Program1

     Look,I just can't help it! Every time I see a  REM  statement  I  just
     have to make a joke about the pop group REM! Sorry!
         The ' symbol is called a REMark.This is  just  here  to  help  the
     programmer to remember where each part of a program starts.This  makes
     the program easy to debugg.(get rid of errors)
         You can type-in REM instead of  '.A  REM can have anything  inside
     it.I've just put in "Program1",but you could put  in  "Fish,Chips  and
     Mushy peas",or "the  local  shop  gets ram-raided".A  REM  dose'nt  do
     anything.They are there for the benefit of the programer.

     CLEAR THE TABLE

                                     50 CLS

     CLS means CLear Screen.When your CPC comes across  one,it  will  clear
     the screen,so you have an empty screen ( apart from the word  "Ready"
     at the top)

     INPUT ONLY

                         60 INPUT"What is your name";a$

     Now we're getting somewhere! The command "INPUT" tells the computer to
     expect the user to type-in something.The above  "What  is  your  name"
     will be printed at the top left corner of the screen.
         The ";a$" means that the name you typed-in will be stored.(More on
     that in just a second)

     SCREEN PRINTING

                                 80 PRINT"Hello"

     PRINT tells the computer to print  something. (in  our  case,the  word
     "Hello") The " marks are important,as these tell the computer that the
     following is not a command but something to be printed on screen.

     LOCATION PLEASE

                             80 LOCATE 8,1:PRINT a$

     On your screen,you can type-in 40 letters from left  to  right,and  25
     from top to bottom.(without the screen scrolling down)  When  you  use
     the PRINT command,the sentance you want printed will be printed at the
     top left hand corner of the screen.In order to print,say,a word at the
     start of the second line,you will use the LOCATE command.
         The LOCATE command is used  to  print  a sentance  anyway  on  the
     screen.The LOCATE command uses  two  numbers,The  first  one  is  what
     column the sentance will start and  the  second  is   what   line  the
     sentance will be printed on.
         The : tells the computer that the next bit  is  different  to  the
     last bit.In other words,it separates two commands.
         The PRINT a$ bit tells the computer to print the name you typed-in
     earlier.

     THE END IS NEAR

                                     110 END

     END ENDS a program.You can access the program again by typeing-in RUN.

     A BASIC WORD

     If you typed in the above program wrong,then a error messege  will  be
     displayed.The messege will tell you which line the error is  in.If you
     get an error type in EDIT followed by the line where the error is in.
         To keep any programs you have written see the "Using  Discs"tutor-
     ial.

     THAT'S ALL FOLKS!!

     Well,that's  it  for  now.In  part  two,we  deal  about   drawing   in
     BASIC and the different modes