Re: [stella] Random number generation on 2600?

Subject: Re: [stella] Random number generation on 2600?
From: Piero Cavina <p.cavina@xxxxxxxxxxxxx>
Date: Tue, 25 Mar 1997 12:27:17 +0100 (MET)
At 10.44 24/03/97 -0700, Nick S Bensema wrote:

>>"Air sea battle" does something strange with VSYNC/VBLANK registers during
>>the screen kernel:
>>>LF0B2: LDA    $B2,X   ;4
>>>       STA    NUSIZ0  ;3
>>>       STA    REFP0   ;3
>>>       LDA    VSYNC   ;3
>>>       LSR    A       ;2
>>>       LSR    A       ;2
>>>       ORA    VBLANK  ;3
>>>       STA    $D9,X   ;4
>>I bet this has something to do with random numbers...
>Perhaps not.  In that context, VSYNC and VBLANK probably don't represent
>VSYNC and VBLANK, but the collision registers that lie in the same location.

You're certainly right, I didn't remember that there where different
registers in the same memory location.

>I thought disassemblers were supposed to catch those differences.

Does this mean that we've found a bug in "Distella"? :-)


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