[Coco] nitros9l2 artifact colors?
Willard Goosey
goosey at virgo.sdc.org
Sun Feb 22 02:05:33 EST 2015
On Sat, Feb 21, 2015 at 10:16:25PM -0500, Arthur Flexser wrote:
> The artifact color mode is controlled by bit 5 of $FF98. Pressing F1 at
> reset sets this bit and puts the CMP colors into the palette registers.
> Hope that helps.
It did, actually!
PROCEDURE foo
a=PEEK($FF98)
a=LAND(a,$F7)
PRINT a
a=LOR(a,$20)
PRINT a
POKE $FF98,a
END
This did invert the artifact colors! (The and $F7 is to clear the
50herz bit which seemed to be set?) Or anyway it made the text screen
turn purple, which is what happens when I hit the RESET switch with F1
down.
Unfortunately, when I started CITY, it reset the colors again, so I
still had a red sky. :-( Apparently the game insists. Or covdg resets
the colors when a graphics mode is selected?
The Disk BASIC version of the program didn't do anything, obviously
BASIC maintains a byte somewhere with what it thinks FF98 should be
and updates it on an interrupt cycle.
Willard
--
Willard Goosey goosey at sdc.org
Socorro, New Mexico, USA
I search my heart and find Cimmeria, land of Darkness and the Night.
-- R.E. Howard
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