04/28/87: HELP!!!! by Delphi, | Category: Delphi - General Information | 1 comment - (Comments are closed)


27159 28APR87-2049 General Information

Can you tell me how to print text
to the “WIDTH40” and “WIDTH80” screens?

I have downloaded several files on the
mmu and gime of the coco-3 and none
of them has the info i need. Oh i’m
using machine language to do this
message printing.

Also could you tell me where the
screen position is stored. The
32 charater position at $88 doesn’t
work for the 40 or 80 screens.


1 comment to HELP!!!!

  • pucc_unknown

    27160 28APR87-2112 General Information
    RE: HELP!!!! (Re: Msg 27159)

    Are you looking for a technical answer on how to write a screen driver
    (such as GETERM has), seperate from all else – to write to 40 and 80 column
    screens, or are you asking for info on how to get BASIC to output stuff to
    the screens? (< -- undoc'd calls)? If you’re talking about trying to get BASIC’s CHROUT to do it…
    I’m a little weak – as I wrote specific routines to do that, in GETERM.. But,
    from my memory, $FE00 & $FE01 contain some form of the byte-offset into the
    screen, and $FE02 and $FE03 contain the X and Y coords of the current cursor
    position.. Also – $E7 contains the text screen type.. 0, 1, 2 (I think) –
    32, 40, 80…

    About a technical approach – writing your own screen IO (which I suggest){_
    Here goes:
    Set up the GIME to the correct display parameters for 40 or 80 columns..
    Set aside a part of memory (preferably not in the $70000-$7FFFF range) for
    the 40/80 screen to reside, and set the GIME to display that address..
    And – every time you get a character to output, map that area of memory
    into RAM somewhere, write out the new character on the screen, update the
    cursor position, re-page the correct memory for the RAM area, and exit..

    (if you need SPECIFICs, leave me mail, and we’ll set up a conference ..)

    Oh – BASIC maps in it’s 40 ad 80 column screens at $6C000.
    – Greg