The 2^16 rollover

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Phil Lamat
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Joined:Wed Mar 06, 2002 9:19 am
The 2^16 rollover

Post by Phil Lamat » Sun May 17, 2020 8:57 pm

I've noticed that roll over in a few games is related with 32768 (2^15) or 65536 (2^16).
What I've listed (according to some description boxes, and some research):

Aligator : roll over every 6553600
Bluehawk : roll over every 6553600
Candy : first rollover 32768, and each 65536 (with score going from -32768 to 32768)
Diverboy : roll over every 655360
Dolmen : roll over every 6553600
Pengo : roll over every 6553600
Pclubys-bl : roll over every 655360
Polyplay-mm : roll over every 65536
Superx : first rollover 3276800, and each 6553600
Zipzap : roll over every 6553600

I suppose the list is much larger than that, maybe someone can enlarge it ...

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Joined:Sun Mar 24, 2002 8:28 am

Re: The 2^16 rollover

Post by Novice » Tue May 19, 2020 11:59 am

defcon =5

the most serious 2^16rollover trouble is burning force (1989 namco).

at 3-2,4-2 and 5-2, run half of stages with maximum speed, you will get a double .will be given twice score until game over.
get double twice, then will be given 4 times score. get double 3 times, then 8x.
remaining bonus is 144,640 point per every ship when you get 3 doubles.(8x)
it is 800K with rollover.

this bug makes correct play as (get double ONLY at 3-2 and 4-2.)
The optimal solution changed due to a bug.
gamest record holder greeN wOOds send to the marp this one.(4x) ... e=emb_logo
play got all doubles.(8x)
DEFence CONdition
WAR 1<< >>7 PEACE

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