by Nukey Shay on Sun Jun 24, 2001 9:44 am
The split-screen makes the 133rd board unbeatable. This effect happens when one of the game's counters attempts to have a value >255 (the largest value possible in one byte). This results in the counter rolling back to zero and setting the "carry" flag, and the game attempts to display the "fruit" for board zero (which does not exist) on the right side of the board. You can see this effect in Mame by having the cheat code force these values, or use a level skip cheat to bypass this limitation.
Many 8-bit games have problems with these counters (since programmers did not figure that people would even get that far). Another example is NES Super Mario when attaining too many extra "lives", it uses 7 bits (128=0) to store the value. I found one myself by reaching level 257, or level 1 rolled over, in Atari 800's Atarisoft version of Dig Dug (it does not have a vertical tunnel, since it is dug out when you start a new game). Dunno if this happens on the arcade version, tho.
Not as cool as PacMan's glitch, I know.
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If the byte rolls over, we'll all be dead.
[ 24 June 2001: Message edited by: Nukey Shay ]