Re: A83: Program creation <--- For Ian Graf.
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Re: A83: Program creation <--- For Ian Graf.
the strangest thing happened. i know i sent this message to the list,
it's even in the archive, but it wasn't in the digest when i received
it. so just to make sure everyone got it i'm sending it again.
>
> 1) ldir stands for
>
> ld: load
> i: increment
> r: and repeat
>
> what this does is copies the byte hl points to, to the byte de points
> to, and decrements bc. then it increments both de and hl and repeats
> this process untill bc=0 (remember at each pass it decrements bc)
>
> so if you wanted to copy a pic you made with pic83 this is what you
> would do:
>
> ld hl,pic ; where to copy from- points to the pic data
> ld de,plotsscreen ; where to copy to- points to the graph buffer
> ld bc,768 ; the number of bytes to copy-
> ; 12 bytes per row x 64 rows = 768 bytes
> ldir ; now copy, byte by byte
>
> 2) the "prgm" token (in hex) is 5F. in order to add it to your program
> do this:
>
> .db $5F,"IAN"
>
> that would be prgmIAN
>
> 3) the data for the program you wanted to make would be this
>
> .db tLbl,"1",tEnter
> .db tDisp,tString,"IAN MAKES GREAT PROGRAMS",tEnter
> .db tPause,tEnter
> .db tGoto,"1"
>
> ; :Lbl 1
> ; :Disp "IAN MAKES GREAT PROGRAMS
> ; :Pause
> ; :Goto 1
>
> the only thing i had to change was the message. as you probaly noticed
> they are all caps. in basic it is the biggest pain in the ass to use
> lower case because they have to be 2 byte tokens, and there isn't
> actually a character for every letter. to answer your question of how to
> start a new line that is what "tEnter" does.
>
> one thing to always remember is when you create the program, make sure
> it is as long as the data you going to be copying to it. for example the
> program in number 3 would be 34 bytes long.
References: