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PostPosted: Mon Mar 04, 2013 9:05 am 
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Week 9's project might interest you guys. I'm taking a look at the EMS cartridges and their multi ROM protocols.

http://blog.gg8.se/wordpress/2013/03/04 ... fects-you/


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PostPosted: Mon Mar 04, 2013 1:27 pm 
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I didn't know anything about configuration mode but I'm not surprised it's absent from the 64M carts. That's why all the fixes are needed. Really is a shame that they would *remove* functionality. Why you would go from having some protection for your Master Bank Register to having none makes no sense. Ofcourse the vast majority of games don't bother it but some certainly do. Donkey Kong Land II if I recall does bother it but the rom is so jam packed I didn't see any safe area to add code to fix it.

It'll be nice when eventually someone, perhaps Krikzz, develops a new Gameboy Flash cartridge. Too bad they couldn't have left that critical functionality in the 64M version.


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PostPosted: Mon Mar 04, 2013 10:58 pm 
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I can think of two reasons.
1) The guy who was good CPLD programming quit and they could no longer get the old logic to work.
2) They wanted to use a cheaper CPLD to save money. However, looking at the datasheet, both the old and new CPLD have 64 macrocells, so superficially it shouldn't matter unless the new chip was incompatible with the old layout.
Or, there IS master protection in hardware which no one knows how to access, and is not used by any known menu ROM. Maybe I should ask EMS about this, but previously when I've asked about technical details about their products, they have just said it was a secret they couldn't share.


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PostPosted: Tue Mar 05, 2013 11:07 am 
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Perhaps if it is present but unknown the powerup state decides it is in "Config mode". If you could find it, that would solve some problems. It's a shame though since it should have both the Bank 00 to 01 behavior option and the Register protection.


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