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1. NO BLATANT PIRACY. This includes reproducing homebrew less than 10 years old, with the exception of free software.
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3. Be nice. See RFC 1855 if you aren't sure what this means.



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PostPosted: Sat Dec 12, 2015 6:47 pm 
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Joined: Mon Jun 15, 2015 8:43 pm
Posts: 20
can you use one of those snes boards with two mask roms to use two 27c040 to create a 1MB repro? I know people would usually use them to make a 2MB with two 27c801 but I have none of those and many 040

if you can, how would I split the rom?


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PostPosted: Sat May 14, 2016 6:36 pm 
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Joined: Wed Oct 21, 2015 4:26 pm
Posts: 12
Not easily, you'd have to modify the decoder so that it enables ROM2 past >512kB into the ROM instead of 1MB (so at A19 instead of A20). That alone would be tricker than just getting a 27c080 or a eeprom adapter board.


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PostPosted: Sat May 14, 2016 6:55 pm 
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Joined: Sun Apr 13, 2008 11:12 am
Posts: 8532
Location: Seattle
Rewiring a small DIP IC is no harder than rewiring for a ROM.

If a board with a MAD-n instead of a 74'139 or 74'00 .... you'll need this.


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