Previous | Next
| From: siz (all posts)
Date: 1999-03-22
Subject: Re: Lightpen
|
On Fri, 19 Mar 1999 racs@fs2.bdtf.hu wrote:
> > Hm. I missed it. $FF1C and $FF1E is the vertical and $FF1E is the
> > horizontal. but it's shifted one bit right, so the least significant bit
> > is not present.
> That is right, but there is no possibility of using this registers for an
> acceptable resolution. Main processor is far too slow for this.
> When sign came in you need at least 3 op to execute while read
> from $FF1C, and as you said, LSB is not present there. (Cannot be
> used for precise horizontal position.)
Hm. In multi-color mode it's just enough 'cause it doubles the pixels, in hi-res mode you would need some more precise positioning but i don't know if there would be any.
> > Yes. I looked for it and found. $FD0D is the "Program-Reset/Status"
> > register of the ACIA. (Program reset for writing and status for reading)
> >
> > It's layout:
> That is all nice, but I see no connection then in these two stories...
I just wrote the correct joystick and keyboard handling... :)
> Lavina's picture shows there is nothing but a joy-port connection.
> The program might be wrong then?
Maybe it's for an other lightpen that uses user port.
--
Szell Imre (Siz)
siz@adam.hu
|
| |
Copyright © Plus/4 World Team, 2001-2024. Support Plus/4 World on Patreon |
