    PERSISTENCE OF VISION PRESENTS 
DISC 109.        RELEASE DATE   6 APRIL 92         ALL CODE BY    MAC SYS DATA 
      GRAFIX BY    MAC SYS DATA       MUSIC BY    LOTUS.      
SO I SAID TO THE GUY WITH THE LONG NECK... GIRAFFE TO!!   
     THIS IS MAC SYS DATA OUT OF THE ASYLUM AT LAST AND ONTO 
A KEYBOARD.   NO WAY MAN IN A WHITE COAT I'M FREE....   
      CAN YOU READ THIS?      NO?    THEN TOUGH!       
       I WAS SITTING THERE ON THE BOG PUZZLING OVER LIFE 
IN GENERAL WHEN I HAD A FLASH OF INSPIRATION.      
ONCE BACK ON MY STE I STARTED WRITING IDEAS DOWN BEFORE I FORGOT THEM. 
  3 HOURS OF CODING AND IT WAS DONE, THE RASTER SCROLLER!     IF 
YOU EVER WONDERED HOW THIS WAS DONE THEN PUZZLE OVER IT NO MORE 
'CAUSE I'LL TELL YOU LATER ON....        THIS DISC WAS GOING TO 
BE A TCB TRACKER BUT THE DAMN THING KEPT GOING WRONG EVEN THOUGH 
I ONLY USED THE REGISTERS I WAS SUPPOSED TO....     
           WELL ONCE AGAIN THE P.O.V. MACHINE HAS 
STARTED UP AND I EXPECT ALL THE PD LIBRARIES WILL BE GLAD 
TO HAVE RECEIVED SOME NEW MENUS.    I HOPE TO SEE SOME OF THE NEW 
MENUS ADVERTISED SOON.             I HOPE EVERYONE HAS GOT 
THE ST FORMAT WITH COVER DISC 33 ON AS IT HAS A DEMO COPY 
OF 'LEANDER' WHICH BORIS OF P.O.V. WROTE.           IF YOU 
ARE CLEVER ENOUGH YOU CAN DEPACK THE CODE WITH ICE 2.4.  ONCE 
DEPACKED YOU WILL SEE A MESSAGE PROVING HE CODED IT......    
         RIGHT HERE COMES THE GREETINGS....          
    HI TO      BART,    DEL,    MARTIAN,    
BILBO,    MUG UK,    SPEED,    DELTA FORCE,    
ADRENALIN,    DR. SYNE,    
INNER CIRCLE,    ERIK PLANKTON AND BLIND BASTARD,    
NOW 5,    UTOS,    THE ENTERPRISE,    
ELECTRONIC,    KGB,    THE FORCE,    PIXEL TWINS,    
NOD,    ZOGG AND THE WATCHMEN,    
SEWER SOFTWARE,    EMPIRE,    FACTORY,    
REPLICANTS,    ETERNAL DEVELOPMENT,    
HAPPENING BOIZ,    OXYGENE CREW,     GENESIS INC.,    
MAD VISION,    CYNIX,    HOTLINE/MCA,    
DELIGHT,    ALTAIR    AND    MR.X.          
IF YOU'RE NOT ON MY GREETINGS LIST AND HAVE REGULAR CONTACT 
THEN GET IN TOUCH AND COMPLAIN.          
WHILST I REMEMBER I WOULD LIKE TO TELL EVERYONE ABOUT BATH BBS. 
  I USED TO LOG ONTO THIS UNTIL IT WENT TO A SUBSCRIPTION 
BUT I LOGGED ON RECENTLY TO HAVE A LAUGH.     WHILST MESSING 
AROUND I NOTICED IT HAS 'GOODMAN PDL' LIST ON AND YOU CAN 
LEAVE A MESSAGE FOR ST-FORMAT.     I DIDN'T BUT I WAS TEMPTED 
TO HAVE A GO AT MR.GOODMAN (WE STILL HAVEN'T FORGIVEN YOU 
FOR BANNING P.O.V. DISCS).       I'VE BEEN BUSY PHONING 
MANY BBS LATELY FROM WORK IN MY DINNER HOUR.   I USE 
THE WORKS AUTO-DIALER AND DOWNLOAD SOFTWARE TO MY PC. AFTER 
PUTTING IT ON 3.5 INCH DISCS I LOAD IT ON MY STE AND DEPACK IT. 
    I'VE HAD ABOUT 1 MEG OF STUFF SO FAR AND THERE IS PLENTY 
TO GO.    THE ONLY PROBLEM IS THAT AT 2400 BITS PER SECOND IT IS 
PRETTY SLOW (NOTE I SAID 2400 BPS NOT BAUD).    I WISH MORE 
OF THE BBS HAD COMPRESSION MODEMS AS YOU CAN GET A HIGHER 
THROUGHPUT AT THE SAME SPEED - IF YOU HADN'T GUESSED, I'M 
A NETWORK SPECIALIST WHO FIXES FAULTS ON BOTH THE DATA AND 
VOICE CIRCUITS.     HEY FOUNDATION BBS, I LIKE YOUR BOARD BUT 
IT TAKES TOO LONG TO GO THROUGH YOUR LIST....               
OH YEAH WHILST I REMEMBER,   HEY RUTHLESS ASK MEMBERS OF 
ADRENALIN WHAT THEY WERE CALLED BEFORE THEY JOINED ADRENALIN.....          
   RIGHT THIS IS THE END SO GO AHEAD AND RUN A DEMO.
                                
                                                           
                                                           
OKAY ALL THE LAMERS SHOULD HAVE GONE SO I'LL EXPLAIN THE 
TECHNIQUE OF THE SCROLLER.     FIRST DEFINE A PICTURE WITH 
7 DIFFERENT BANDS OF COLOUR GOING VERTICALLY UP THE SCREEN. 
       NOW DEFINE A FONT 7 PIXELS WIDE.          
OKAY THIS IS THE CLEVER BIT....      WRITE A SCROLL ROUTINE 
THAT USES A 200 LINE BUFFER.    NOW SET UP TIMER B 
(HBL) TO TEST EACH BIT OF THE BYTE IN THE BUFFER.  
  START AT THE MOST SIG BIT AND WORK DOWN TO THE LEAST SIG BIT. 
    YOU SHOULD BE TESTING THE BITS THAT MAKE UP THE LETTER SO 
WHEN YOU TEST A BIT AND THE RESULT IS ZERO (BLANK) THEN 
DEFINE ONE OF THE COLOURS IN THE VERTICAL BANDS BLACK.  IF 
THE RESULT IS POSITIVE THEN DEFINE ONE OF THE COLOURS SO YOU 
CAN SEE IT.     DO THIS FOR THE SEVEN BITS AND YOU SHOULD SEE 
A PIXEL LINE APPEAR WITH SOME COLOUR.   REPEAT THIS PROCESS 
OF TESTING THE BITS FOR EVERY LINE OF THE SCREEN AND THE 
WHOLE BUFFER SHOULD APPEAR AS CHARACTERS SHOWN WHERE THE 
VERTICAL COLOUR BANDS ARE.     EVERY VBL MOVE THE BUFFER 
UP ONE BYTE AND PUT A NEW FONT BYTE AT THE BUFFER END.    
    YOU WILL PROBABLY FIND THAT THE TESTING ROUTINE TAKES 
QUITE SOME TIME AND SO YOU WILL PROBABLY END UP TESTING THE 
BITS EVERY 2 VERTICAL LINES.     IF YOU CAN'T UNDERSTAND 
THE PRINCIPLE THEN LOOK OUT ON THE PD SCENE IN ABOUT 3 MONTHS 
TIME AS I WILL BE RELEASING THE SOURCE CODE FOR ALL TO SEE....  
                                                          