----- Original Message -----
From: Thomas Jentzsch <tjentzsch@xxxxxx>
To: <stella@xxxxxxxxxxx>
Sent: Monday, November 26, 2001 5:06 AM
Subject: Re: [stella] VCS.H standardization
> (BTW: What is at $285? TIMINT? It is missing in all include files I know
and it's not documented, but DiStella knows it.)
I´ve asked this not so long ago:
>I always thought that $285 was a timer mirror, look what Dragon fire does:
>
> 12DB 2C8502 BIT $0285
> 12DE 10FB BPL $12DB
Here´s what Eckhard Stolberg answered :
> This is exactly what I tried to describe above. If you start
> a timer with interrupts enabled ($29E instead of $296 for TIM64T),
> then bit 7 of address $285 will go high when the timer wraps around
> from $00 to $FF. Therefore the above loop will wait for the timer
> to expire without having to change the content of any of the three
> processor registers by loading from INTIM.
The PIA has other registers too, but they´re not needed for atari games
development, so I don´t think they should be added to stella.h
Bye,
Nicolás.
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