[A86] Re: The f'n 86 screen
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[A86] Re: The f'n 86 screen
I would assume that only your code has this problem, and therefore it is =
an=20
error of yours and not a hardware problem with the calc. My first though=
t=20
in reading it was that you did something really weird, likely accidentall=
y.=20
That really weird thing would be changing the number of bytes per row tha=
t=20
the screen uses, using port 4. Or you possibly changed the interrupt=20
speed. But, I think the more likely problem is that your grayscale routi=
ne=20
is faulty. It sounds like the planes aren't aligned. Why are you using=20
3-level instead of 4-level? With a 1:2 ratio 4-level looks good and is=20
essentially flicker free (flourescent light makes it barely noticable). =20
Try some code to make the 1/4 of the screen black, the next 1/4 dark grey=
,=20
the next 1/4 light gray, and the bottom white. You will then know if you=
r=20
grayscale routine is working correctly.
> I have been having many problems with the screen of the Ti-86. =
In
> several of my programs, the sprites that I draw (like bullets going
> vertically up the screen) get very dim, no matter what the contrast.=20
> Also, the little sprite at the bottom of the screen that doesn't move
> gets a little hole in the middle of it where the line of bullet sprites
> are above it. When I used halts to slow down the cycles of the program=
,
> the dimness will flip between the top half of the screen to the bottom
> half of the screen every few seconds. If I disable interrupts and loop=
a
> large number of loops to slow down the program, the graphics get all
> choppy and the problem with the dimness affects about half the screen,
> but scrolls vertically down and restarts at the top of the screen. I
> also have this exact problem in my 3-level grayscale routine. If you
> know what this is or know how to fix it, please let me know, because I
> kinda have no clue.
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