>Where is the
>start address located in all the different sized
>binaries? What are the different sizes of binaries
>available? 2048, 4096, 6144, 8448? Is it the
>last few bytes of a 4096 byte image? Should
>a 2048 byte .bin be turned into a 4096 byte
>image by sending it twice, like $f000-$f7ff and
>$f800-$ffff are mirrors of each other?
Well, your best bet is to look at Makewav's source code. Basically,
the start address is at $ffc and $ffd of a 4k ROM and $7fc and $7fd of a 2k ROM image (These are ROM addresses, not 2600 addresses!!!). In the Supercharger ROM image, the start address is is at $2000 and $2001. Start addresses are stored in lobyte and hibyte format.
As far as the 2k ROM images go, you could double up the image, but it wastes time. You can determine which bank to load the game into by checking the start address. If the start address hibyte is < $f8 then load it into the lower 2k, otherwise, load it into the upper 2k. Some 2k games are sloppy and refer to the code in two ways. For example, one section could do a JSR $F123 and another JSR $F923. In some 2k carts, and address line is tied high or low, so these addresses are equal.
Good Luck,
Bob
>Wow, lots of questions, hope I made myself clear.
>My goal in this is to be able to play all the
>.bins available, not just 4096 byte ones that
>run at $f000.
>--
>Robin Harbron <robinh@xxxxxxxxxxxxxxx>
> http://www.tbaytel.net/macbeth
>
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Wanna write a game for the Atari 2600?
Check out http://www.novia.net/~rcolbert
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