Subject: Re: [stella] Interesting find in Centipede...or at least I think so :-) From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx> Date: Thu, 5 Aug 2004 23:13:18 +0200 |
>> I also wonder if Centipede was originally targeted for 4K. If you look at BANK0 the start vector has $F000. Is this normal? Does it matter what's in the start vector of the first bank anyway? << $F000 is a perfectly fine start vector for a 2600 game, as long as there is some meaningfull code at that address. ;-) 2600 games can start up in any bank, so you have to have initializing code in all of them. Usually only one bank contains the actual init code, while the others only have bankswitching code into the real startup bank. Centipede for example has 'STA $FFF9' at address $F000 in the first bank. This switches into the second bank where the real initializing code starts at address $F003, so that the code execution can continue there. Ciao, Eckhard Stolberg
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