Talk:Action 53 mapper: Difference between revisions
(→Writable flash: new section) |
m (Tepples moved page User talk:Tepples/Multi-discrete mapper to Talk:Action 53 mapper: As far as I can tell, this has become the accepted name for this MMC1-class multicart mapper) |
Latest revision as of 15:32, 9 June 2016
Pin count
Do few-enough-pin PALs/CPLDs still exist such that pointing out "there's no reason to connect D6 at all and D7 in mode selection could be changed to D5 and free up another input pin" is even remotely useful?—Lidnariq 19:25, 13 October 2012 (MDT)
- It might free up pins in the current design, but I'm thinking ahead to how oversize expansions would work should the time come. And I don't see how you're getting 25 pins; it looks like 28 to me, especially with the equivalent of a 7420 for PRG RAM decoding and bus conflict avoidance included. --Tepples 20:30, 13 October 2012 (MDT)
- I don't think I said 25 pins anywhere? Unrelatedly, my having suggested D5 might not be the best because of this future-proofing you said; using D4 or D1 might be cleaner. But regardless, it looks like there aren't any PALs or CPLDs both cheaper and fewer pins than the XC9536XL infiniteneslives had specified in the forum, so I think my initial "hey, maybe..." is irrelevant. —Lidnariq 01:19, 14 October 2012 (MDT)
512-KiB Mode - Is it Possible?
I don't think you can fit a 512-KiB game for use in that mapper right now, I think you can replace a mode, or use a new mode if it fits? I possibly doubt it though due to constraints...
Even then, I like the idea of a multicart like this! --Hamtaro126 01:56, 14 October 2012 (MDT)
- An oversize BNROM game will fit, though only one such game at a time unless each game's bank number table is modified to correspond to its position in the cart. This is the same technique that I had planned for BNROM games in Action 53 before I learned that homebrew developers prefer UNROM over BNROM. --Tepples 22:15, 3 November 2012 (MDT)
Writable flash
There are rumors on the BBS that INL will make boards that allow in-circuit programming of the beginning of the PRG flash in 4096 byte sectors as a method for saving the game. An extra 8 KiB of SRAM will be mapped at $6000 for managing a log-structured file system. I think I know how to represent this in NES 2.0: if non-backed and backed PRG RAM are present, the non-backed memory is SRAM at $6000 and the backed memory replaces the first pages of the ROM and is writable through Common Flash Memory Interface sequences. I'm waiting on INL for details before I add it. --Tepples (talk) 20:08, 31 January 2014 (MST)
