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2009-10-10
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133 lines
╓─├ ╨ROGRAMMING ╘OOLS ┬Y ─ALE ╥AY
╘HE FILES INCLUDED IN THIS ARCHIVE ARE:
╓─├─┼═╧ - A BASIC PROGRAM THAT SHOWS HOW
THE ML WORKS
╓─├─┼═╧.╙ - ═ERLIN SOURCE CODE FOR THE ML
╓─├─┼═╧.╧ - THE ML OBJECT CODE
╓─├╙╧╒╥├┼.╘╪╘ - THIS IS A PRINT OUT ,IN ╨ET┴SCII, OF AN
ASSEMBLY OF THE SOURCE. ╔T IS INCLUDED
FOR THOSE WHO USE A DIFFERENT ASSEMBLER
╓─├─┼═╧.─╧├ - THIS DOC FILE
╔ FOUND MYSELF WRITING A PROGRAM THAT WOULD BENEFIT FROM SOME OF
THE CAPABILITIES OF THE ╓─├ CHIP ╔ HAD READ ABOUT IN VARIOUS
MAGAZINES. ╔ THOUGHT IT WOULD BE NICE, SINCE THE PROGRAM HAS TWO
MAIN SCREENS, TO USE THE UNUSED MEMORY IN THE ╓─├ RAM SO THAT ╔
COULD PRINT BOTH SCREENS AT THE START OF THE PROGRAM AND THEN
TOGGLE BETWEEN THEM. ┼VEN 128S WITH ONLY 16╦ OF ╓─├ RAM CAN DO
THIS.
═Y NEXT PROBLEM AROSE WHEN ╔ FOUND THAT ╔ WANTED TO MAKE HELP
MESSAGES AVAILABLE TO THE USER. ╘HE PROBLEM ╔ HAD IS THAT THE
PROGRAM READS AND DISPLAYS INFORMATION FROM DISK. ╘HE DISPLAY IS
A FULL SCREEN SO ╔ COULDN'T RESERVE SCREEN AREA FOR THESE
MESSAGES WITHOUT MAKING THE AREA FOR THE DISPLAY SMALLER. ╔ WAS
ALREADY USING THE EXTRA SCREEN SO ╔ FOUND ╔ NEEDED TO BE ABLE TO
SAVE AN AREA UNDER A WINDOW AND THEN RESTORE IT. ╘HIS TECHNIQUE
CAN ALSO BE USED FOR INPUT BOXES OR ERROR MESSAGES.
╔ DUG THROUGH MY OLD MAGAZINES AND FOUND ROUTINES THAT WERE
DESIGNED TO DO THESE THINGS. ═Y PROBLEM WAS THAT ╔ DIDN'T KNOW
ENOUGH ABOUT ═╠ OR THE ╓─├ CHIP TO UNDERSTAND WHAT THEY WERE
DOING. ╔N ORDER TO MAKE USE FO THEM IN MY PROGRAM ╔ HAD TO
UNDERSTAND THEM ENOUGH TO MODIFY THEM. ╙O ╔ EMBARKED ON A
LEARNING BINGE.
╙URPRISINGLY THE BOOK ╔ FOUND MOST HELPFUL LEARNING ABOUT THE
╓─├ WAS THE ├OMMODORE 128 ╨ROGRAMMER'S ╥EFERENCE ╟UIDE FROM
┬ANTAM ┬OOKS. ├HAPTER 10 OF THIS BOOK COVERS PROGRAMMING THE ╓─├
IN DETAIL. ╔ ALSO FOUND THE ┴BACUS BOOKS ON THE 128 VERY
HELPFUL. ╞OR THE ═L PART ╔ USED 128 ═ACHINE ╠ANGUAGE ╞OR
┬EGINNERS BY ╥ICHARD ═ANSFIELD FROM ├╧═╨╒╘┼! ┬OOKS. ┴S ALWAYS
═APPING ╘HE 128 BY ╧TIS ╥. ├OWPER (ALSO FROM ├OMPUTE!) WAS A
VALUABLE REFERENCE.
╙O, WHAT ╔ ENDED UP DOING WAS WRITING MY OWN ROUTINES THAT FIT
MY NEEDS. ┴LONG THE WAY ╔ LEARNED SOME STUFF AND ,IF YOU AREN'T
GETTING PAID TO PROGRAM, ╔ GUESS LEARNING IS REALLY THE GOAL. ╔F
YOU ALREADY KNOW THIS TERRITORY THEN YOU PROBABLY ARE WASTING
YOUR TIME. ╔F NOT THEN ╔ AM GOING TO EXPLAIN HOW THE ROUTINES
WORK AND WHY ╔ DID THINGS THE WAY ╔ DID. ╔ AM ╬╧╘ AN EXPERT, ╔
AM JUST TRYING TO SHARE WHAT ╔ LEARNED WITH OTHERS.
╔F YOU SEE A BETTER WAY OR FIND A BUG PLEASE BE SURE TO LET ME
KNOW. ╔ CAN BE REACHED AT:
─.╥┴┘1 - ON ╟┼NIE
╒╙ ═AIL - ─ALE ╥AY
> 1 <
╓─├ ╨ROGRAMMING ╘OOLS ┬Y ─ALE ╥AY
2101 ╫. 49TH ╨L.
╟ARY, ╔N. 46408
├OMMENTS ARE WELCOME.
***** ┬┴╙╔├ ─┼═╧ *****
╘HE BASIC DEMO WILL LOAD THE MACHINE LANGUAGE AND THEN ASK IF
YOU HAVE 64╦ VIDEO RAM. ╔F YOU DO THE ═╠ ROUTINE TO INITIALIZE
THE VIDEO RAM WILL BE CALLED. ╔F YOU HAVE 64K VIDEO RAM THREE
SCREENS WILL THEN BE PRINTED USING DIFFERENT AREAS OF ╓─├
MEMORY. ╫ITH 16K VIDEO RAM ONLY TWO SCREENS WILL BE DRAWN.
┴FTER ALL OF THE SCREENS ARE DRAWN WINDOWS WILL CLEAR ON THE
SCREEN AND THEN THE ORIGINAL CONTENTS WILL BE RESTORED. ╘HERE IS
A DELAY BUILT INTO THIS LOOP SO YOU CAN SEE WHAT'S GOING ON.
┴FTER EACH WINDOW HAS APPEARED ON THE FIRST SCREEN ANOTHER
SCREEN WILL BE DISPLAYED AND THE WINDOW ROUTINE WILL RUN AGAIN.
╔F YOU WANT TO END THE DEMO PRESS ╤. ┘OU CAN CAUSE THE DEMO TO
SKIP BETWEEN SCREENS BY PRESSING 1, 2, OR 3 FOR THE SCREEN YOU
WANT TO VIEW.
╘HE PURPOSE OF THE BASIC DEMO IS TO SHOW YOU HOW YOU CAN USE THE
═╠ IN YOUR OWN PROGRAMS. ╠IST THE DEMO AND LOOK IT OVER. ╘HE
SCREENS ╔ DREW FOR TESTING THE ═╠ ARE JUST COLORED PATTERNS, BUT
THE SAME ═╠ CAN BE USED TO RECALL A HELP SCREEN, A MENU, OR SOME
OTHER EFFECT FOR YOUR PROGRAM. ╘HE ABILITY TO USE MULTIPLE
SCREENS BY SWITCHING WHICH AREA OF ╓─├ MEMORY IS ADDRESSED PLUS
BEING ABLE TO RECALL DATA FROM A RAM BUFFER OUTSIDE OF THE ╓─├
GIVES YOU A LOT OF FLEXIBILITY
> 2 <