Re: [stella] Random Numbers

Subject: Re: [stella] Random Numbers
From: Thomas Jentzsch <tjentzsch@xxxxxx>
Date: Tue, 27 Jan 2004 22:11:36 +0100
David Davies wrote:
> Just started on a game for the 2600 based on the 1977 arcade game,
> Depthcharge (well, okay, it's a straight port with added game variations).
> It's my first attempt at taming the 2600, so please be gentle :-)


> I've been doing some thinking as to what needs doing on the game. I
> definately need a random number generator. Is there a way of doing that on
> the 2600?

This is as simple as it gets:

RAND_EOR_8 = $8E; or 95,96,A6,AF,B1,B2,B4,B8,C3,C6,D4,E1,E7,F3,FA

    lda     random
    bcc     .skipEor
    eor     #RAND_EOR_8
    sta     random

Just make sure that you initialize random with a value != 0 at
Have fun!
Thomas Jentzsch         | *** Every bit is sacred ! ***
tjentzsch at web dot de |

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