Talk:NES 2.0 Mapper 319

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Revision as of 20:29, 16 May 2018 by NewRisingSun (talk | contribs)
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typo?

FCEUX's source in boards/hp898f.cpp swaps the location of the two registers relative to what's documented here. —Lidnariq (talk) 17:32, 15 May 2018 (MDT)

Additionally, the description here (modifying overriding PRG A16 with CPU A14, instead of PRG A14 with CPU A14) really sounds like this description is a misdump. —Lidnariq (talk) 19:13, 15 May 2018 (MDT)

I have corrected the relative register location. Not sure what you mean by "misdumped description " in the second part. If the 16 KiB PRG-ROM bank bit 2 (4s) is modified, it's going to affect PRG A16, not A14. NewRisingSun (talk) 23:52, 15 May 2018 (MDT)
Or do you mean the ROM (and not the description) is misdumped, having the banks in a supposedly implausible order? I have not dumped the cart myself, and I am not going to assert bad dump status without having seen the board topology. NewRisingSun (talk) 00:10, 16 May 2018 (MDT)
That is exactly what I mean. There are a wealth of other boards which support both NROM-256 and NROM-128 by relaying or overriding CPU A14; this cart is unique in interpreting that signal as connecting to PRG A16 instead of A14. —Lidnariq (talk) 14:09, 16 May 2018 (MDT)
Here are the values that the menu is writing and the resulting 16 KiB bank numbers at 8000 and C000 according to the A16 description:
               Written 16K Banks# @
               Value   8000    C000
Menu		38	07	07
Super Mario    D0	02	06 *
Star Force	C8	01	05 *
Tennis		98	03	03
F-1 Race	80	00	00
Lode Runner	A0	04	04
Duck Hunt	88	01	01
Galaxian	38	07	07
(The cart has Inventor's renamed hacks of the games; I used the original names.) I'm struggling to think how to rearrange the banks in such a way that Super Mario could work with an A14 override (yielding in banks 02,03 instead of 02,06) without breaking Tennis. NewRisingSun (talk) 14:29, 16 May 2018 (MDT)