Re: [stella] Dumb newbee question

Subject: Re: [stella] Dumb newbee question
From: Erik Mooney <erik@xxxxxxxxxx>
Date: Wed, 20 Mar 2002 21:51:14 -0500
On Thu, 21 Mar 2002 09:17:50 +1100, you wrote:

>Personally I find it rather odd the read/modify/write of VSYNCH and WSYNC)
>I'd just set or clear the bit with a direct write, myself.
>It's never actually occurred to me during my programming, but are the
>hardware registers (VSYNCH, WSYNCH, etc. reliably readable)?  I would have
>expected to have used shadow registers in RAM and always write the shadow
>values to the HW regs when modifying regs.

No -- when you read a hardware register, you get a collision register, which
are from $00 to $0E and are mirrored at every %0xxx0000.

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