Re: A89: ROM 1.05 and grayscales


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Re: A89: ROM 1.05 and grayscales




My guess is that ROM v.2 will have the same problem.  I think we'll have to
find a more permanent solution than just using v.1.00

What is the max speed the auto-int 5 can run on?  What is the min. speed
necessary for realistic grayscale?  It seems like if you want 30 fps, you'd
need 4 interuppts per frame, so you'd want a speed of about 120 Hz.  Can int
5 run this fast?  Would it need to run faster?

Here's an idea.  Why not run the TIOS int1 routine on auto-int 5, and use
auto-int 1 exclusively as the grayscale screen-switcher?

Mark Leverentz
----- Original Message -----
From: <ComAsYuAre@aol.com>
To: <assembly-89@lists.ticalc.org>
Sent: Friday, August 27, 1999 9:29 AM
Subject: Re: A89: ROM 1.05 and grayscales


>
> We could all just boycott rom 1.05 and have all asm support be for 1.00.
> That seems to be what most people are doing anyway.
>
>
> In a message dated 8/27/99 9:14:53 AM Eastern Daylight Time,
> xvassor@mail.dotcom.fr writes:
>
> > You maybe know that the grayscales no longer work on the new 1.05 ROM
> >  I think I've found out why : you know the greyscale handler relies on
auto
> >  interrupt one which runs at 300 Hz. This handler switches 2 virtual
screens
> >  in B&W, giving the impression of 4 gray levels, and then RUNS THE OLD
AUTO
> >  INT 1 HANDLER, ie the TIOS one in most cases.
> >
> >  The problem is that it seems that the auto int 1 handler from the new
1.05
> >  ROM is too slow to allow a sufficient refresh rate -> there is no
> >  impression of 4 grayscales..
> >
> >  So, what ? The solution'd be that the grayscale handler no longer calls
the
> >  old auto int 1 handler, but this will prevent the program to use
functions
> >  such as userlib::idle_loop, as well as the APD features when it is
running
> >  in grayscales.
> >
> >  What should I do ?
>
>


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