Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!bcm!dimacs.rutgers.edu!rutgers!cbmvax!cbmehq!cbmger!peterk
From: peterk@cbmger.UUCP (Peter Kittel GERMANY)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: drawingpad
Keywords: drawingpad
Message-ID: <793@cbmger.UUCP>
Date: 28 Jan 91 14:57:09 GMT
References: <1991Jan25.095710.6716@daimi.aau.dk>
Reply-To: peterk@cbmger.UUCP (Peter Kittel GERMANY)
Organization: Commodore Bueromaschinen GmbH, West Germany
Lines: 48

In article <1991Jan25.095710.6716@daimi.aau.dk> pilgrim@daimi.aau.dk (Jakob G}rdsted) writes:
>Before you read any further: This is just a silly idea I want to tell the
>world about!

Don't be afraid, not silly.

>   The Amiga has got a nice port in which one plugs the mouse, and most
>of the serious programs utilises this to move the pointer about. But
>(especially in Painting programs, but also elsewhere) a mouse is only
>one type of "userinterface", and it could be nice to use a drawing-
>pad (these thingies with a plate and a pencil you move around), but
>this would not be compatible with the mouse interface: The mouse works
>by sending pulses for vertical and horisontal movement. Using a drawing
>pad, you are able to lift the pen from the pad, and put it down elsewere
>on it; here your coordinates are absolute.

Well, normally you are supposed to use the mouse button(s) to indicate
the pen status.

>   The drawing pad of course keeps track of the pen's absolute coordinates.
>Whenever it is lifted, its coordinates are those it had when it left the
>surface. In fact the pad should not keep track of where the pen is, but of
>where the pad wants to tell the computer the pen is. This is quite like
>the "draw continous curve with brush"function in Deluxe Paint - when
>you  move the mouse too fast, you see that the computer in fact draw
>straight lines between checkpoints. The pad should do the same. It should
>sample a checkpoint, then emulate the pulses the mouse would send to
>the computer if moving in a straight line to the new "destination", and
>when it had updated the computer, sample another checkpoint
> (i.e. read where the pen is), and do another emulation of the mouse,
>and so on.(this is why the board would need some chips, as I see it, it
>must be able to do quite a lot of arithmetics)

I only know about a commercial product, the "Easyl" graphics tablet.
This is a high resolution graphics pad for use in CAD and similar.
It comes with drivers that translate the board coordinates to mouse
moves. And it has two buttons that you trigger with your other hand.
Together you can use DPaint quite normally.

And recently there was a discussion here how to connect a Koala pad
from the C64 to the Amiga. As far as I remember they said it could
be done, but nobody gave the real pinout or a listing of the needed
driver (because this would connect to the analog pot inputs and not
to the impulse-driven mouse inputs).

-- 
Best regards, Dr. Peter Kittel  // E-Mail to  \\  Only my personal opinions... 
Commodore Frankfurt, Germany  \X/ {uunet|pyramid|rutgers}!cbmvax!cbmger!peterk